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Echinodermata! Starfish! Sea Urchins! Sea Cucumbers! Stone Lillies! Feather Stars! Blastozoans! Sea Daisies!Marine invertebrates found throughout the world's oceans with a rich and ancient fossil legacy. Their biology and evolution includes a wide range of crazy and wonderful things. Let me share those things with YOU!

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    I've often talked of my love of multi-armed sea stars. BUT brittle stars can have more than five rays (arms) also!!

    So wait, there are ophiuroids (brittle stars, basket stars, etc.) that have MORE than 5 rays?? 
    Most sea stars (close relatives to ophiuroids) have 5 rays, but a significant number of them have more than five rays and there are some entire groups of sea stars (e.g., the Brisingida) which are characterized by having multiple arms (six to 20ish). When sea stars have more than 5 rays there tend to be about 7 to 15 of them. But some, such as the Antarctic Labidiaster can have up to 50.

    What one sees in most  starfish species is that multi-armed sea stars tend to be large, highly mobile and predatory. This tropical, shallow water Luidia maculata for example demonstrates all of those qualities.
    Ninearmed starfish (Luidia maculata)
    In contrast, Multi-armed ophiuroids have different patterns than what sea stars demonstrate. Ophiuroids tend to be either six to seven rayed or 10 or more. Generally none with intermediate arm numbers (i.e., 8 to 9) and no species are known with more than 12 rays.

    Certainly no 20-50 rayed beasts like the sea star Labidiaster. And as we'll see, there's no apparent ecological association with having more than 5 arms in ophiuroids.

    The multi-armed condiiton occurs  in many, many different groups of asteroids throughout evolutionary time (here) and has evolved multiple times throughout the group. This is also the case for brittle stars...
    (My thanks to Dr. Sabine Stohr for assistance with names!)

    Diversity in Multi-armed Ophiuroids
    Most brittle stars have 5 rays. Having more, implies that the extra arms are somehow adaptive or suggest that the added investment to develop one further body part is somehow consistent with the life mode of the animal. Most ophiuroids appear to have a much more invested skeleton compared to asteroids, so it would seem that adding more arms is much more of an investment in development,

    Low numbered multi-rayed brittle star species, those with about six to eight arms are not uncommon and seem to show a fairly diverse range of habitats. But the ones with more than 10 rays are more seldom seen.

    This one for example is Ophiothela danae. 6 rays. These occur in tropical-shallow water habitats and live with their arms wrapped around the stalks of sea fans and sea whips.  Does the sixth arm help facilitate this lifestyle??

    This species appears to be successful. It occurs widely in the tropics and has "invaded" the tropical Atlantic from the Pacific. 

    Tiny colourful brittle stars (Ophiothela danae)
    Here is Ophiactis savignyi, a brittle star that reproduces both sexually and asexually (i.e. it divides in half) brittle star which occurs globally all around the world (read more here). Perhaps its sixth arm is part of the asexual condition? Or maybe its cryptic life style?

    Here is Ophionotus hexactis. Six arms. Adaptive? Predatory? Highly Mobile? An animal I'm not sure much is known about it.

    But on the OTHER hand, here are some Antarctic brittle stars, such as Ophiacantha vivipara which have SEVEN arms. Its a brooding species (i.e., the adults raise babies on their bodies). Not sure how this benefits the animal. Maybe in feeding?  Aids in parental care somehow? Or maybe its just an incidental feature?
    From Antarctic ophiuroid blog

    There are a few more species of ophiuroids that show six to seven arms than I've shown here. But for various reasons (i.e,  I either didn't have pictures of them, space, etc) I haven't included them. Several species of serpent stars in the genus Asteromorpha for example can demonstrate six or seven arms.

    Species with more than 10 arms

    Ophiacantha enneactis & O. decaactis. The genus Ophiacantha, is kind of unusual because it includes several species which possess more than 5 arms (see O. vivipara above).

    Two of them, O. enneactis (illustration-top) and O. decaactis (below) have been collected from the Aleutian Islands in deep-water. O. enneactis is from 549-881 m. And O. decaactis is from comparable depths.

    These are similar species and both are pretty small. What they do down there in the deeps with all their arms is "poorly understood." (i.e. we don't know). Perhaps suspension feeding? Predation?

    Image from page 233 of "Bulletin - United States National Museum" (1877)
    Ophiacantha decaactis Belyaev & Litvinova 1976
    Image from Belyaev & Litvinova 1976
    Astrochlamys sol Probably the winner of ALL the multi-armed ophiuroids though is this species: Astrochlamys sol, a bizarre Antarctic form, which is a member of the Gorgonocephalidae, so its actually a modified basket star.

    I thought Basket Stars already had more than five arms?? 
    Basket stars are a subdivision of ophiuroids called the Euryalida. They tend to have big, thick arms with fleshy tissue covering over their skeleton. These ophiuroids extend their arms into the water column and usually have hooks or long arms to feed on food or prey as it swims by..

    I've written about one particular basket star, Gorgonocephalus here  But there are a fair number of basket stars in cold water and tropical habitats.

    Note that although there seem to be many arms, there are in fact ONLY five. But they branch...
    Northern basket star, Gorgonocephalus arcticus, off Cape St Francis, Newfoundland, Canada

    Below is the underside of Gorgonocephalus, the cold-water basket star from the Arctic/subArctic. Note that only five rays radiate away from its mouth. The  arms bifurcate or split for several iterations away from the five primary rays on the disk..

    That's what makes A. sol, so unusual. It actually has 10 to 11 arms!! Making it the ophiuroid (not technically a "brittle star") with the MOST number of arms!
    Its species name "sol" refers to sun, which likely alludes to its arms radiating away from the mouth.

    This species occurs in the Antarctic in fairly deep depths 300-1200 meters. It was described by the famous echinoderm taxonomist/biologist Theodor Mortensen in 1936 in his HMS Discovery monograph. We apparently don't know much about its biology aside from the fact that its a brooding species and tightly hugs its substrate...
    Image by Igor Smirnov via WoRMS
    On a personal note I'm always fascinated by these forms. Unusual in appearance but also kind of mysterious.  What does it do with all those arms? What is so unusual about deep-sea/cold-water/Antarctic species that they have so many arms? Is brooding related? 

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    So, after all that deep-sea stuff, I thought this week might be a good moment to look at some tropical, shallow-water species....

    Stunning image of the cidaroid Plococidaris verticellata by Shawn Miller
    Plococidaris verticillata, sea urchin

    A fire urchin (probably Asthenosoma) from Puerto Galera, Philippines
    Puerto Galera - Fire Urchin
    More fire urchin love!
    fire urchin

    A magnificent anal sac in Astropyga
    Seaa Urchin
    Another anal sac from a diadematid urchin..

    Details on Mespilia globulus!
    Reaching Out

    The slate pencil urchin Heterocentrotus mammilatus..or swirling maelstrom of the ELDER GODS?
    Pencil urchin  - Heterocentrotus mammillatus
    What lies beneath? the teeth from Aristotle's Lantern! 
    Mouth of a Pencil Urchin

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    Hypselodoris zephyra image by Steve Childs via Wikipedia
    ATTENTION all photographers, divers, bloggers, scientists, natural historians, citizen scientists, museums, zoological parks, aquaria, big ocean organizations, and other colorful mollusk enthusiasts (in no particular order)! 

    Let it be announced herein that October 29th of this year (Thursday) will be SEA SLUG DAY!!  #seaslugday

    So, why "sea slug" and not "nudibranch"? We're going to be focused primarily on nudibranchs, but there's actually a lot of different type of "sea slugs" which many people mistake for nudibranchs or which often get lumped in with them. A brief summary on these relationships are nicely written up on the Wikipedia page.

    Sea hares for example are actually a distinct group from nudibranchs. But they are often regarded as "close" to nudibranchs.
    Aplysia californica, California Seahare
    So, to avoid "nudibranch VS. sea hare" or "nudibranch VS. sacoglossan"arguments and etc. I'm just going with "sea slug".  For the biologists out there: No, its not monophyletic. But its an easy catchall term. and the hashtag is slightly shorter than "nudibranchday".

    Why October 29th for Nudibranch Day?
    Nudibranch Day honors Dr. Terry Gosliner! Biologist at the California Academy of Sciences and one of the world's pre-eminent experts on nudibranchs!! Go here to see more about him October 29th is his birthday!
    In addition to working on nudibranchs, Terry also coined the popular term "Bobbit Worm" for the raptorial polychaete Eunice sp. (many are E. aphroditois).

    Why have a Nudibranch Day? Because they are fantastic animals and I just thought it was just LONG overdue. So I'm just doing it.  To be honest, there was an earlier attempt at "nudibranch week" here. But frankly, other than "during Shark Week" there's no fixed date indicated. Its also not my style to honor something by holding it up a contrarian force to something else. Positivity!!

    We also have Halloween that weekend! I wouldn't mind at all if it extended out to Friday or even the weekend! To 'branch out as it were!! (ha!)

    What better time to celebrate nudibranch diversity???

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    Its October! Which means we are around the corner from Halloween! Many of you have seen how I have expressed a strong interest in Japanese science fiction and pop culture.  One of my starfish has even been made into a toy! 

    My research over the last few years has taken me not only to Japan but also gotten me interested in the nomenclature of various Japanese starfish species!!

    Although many of these are essentially common names, they are surprisingly standardized and are widely recognized in addition to the western Latin names.  While studying these I also encountered a few other cool stories about invertebrates which have been part of Japanese folklore and myth.

    So this week: The Invertebrate-Japanese folklore connection! Names & monsters/spirits inspired by invertebrates!!

    I thank Matt Alt of AltJapan and Dr. Toshihiko Fujita of the National Museum of Nature & Science for providing me with some of the the information in today's post!

    1. The Oni Hitode
      So, the termyokai (妖怪) refers to a spirit or ghost , most of which have a strong root in Japanese folklore and myth. There are a great MANY types, some of which are listed here and Wikipedia of course!  Perhaps one of the types of yokai which I see popularly presented in pop culture and literature and in some Western sources is a demon called an Oni, of which one face is represented below...
    Oni Mask
    The spines on the head are a characteristic feature of this yokai. Its this characteristic which has most likely been lent to Acanthaster planci, the crown of thorns starfish which is known in Japanese as the Oni Hitode or "Demon starfish" 鬼ヒトデ
    Crown of Thorns
    Here's another kawaii I found of the Oni-hitode, which from what I understand was part of a"Kill the crown of thorn starfish" campaign. Acanthaster planci, is a fairly well known predator of coral and has been undergoing massive population booms leading to frequent efforts to remove them.
    From this Japanese site 
    And of course, the inevitable transformation of the crown of thorns starfish into a kaijin or "human sized" monster to be defeated by a snorkel-adorned Kamen Rider! 

    2. Higuruma Hitode (or not?)
    Another cool Japanese starfish name is one this deep-sea brisingid starfish, Brisingaster robillardi.

    I've described brisingid sea stars at length here. Deep-sea species which feed on prey in water currents using "velcro" (tiny claws) on their spines. More great images of these animals here.

    The common name for this species is called the Higuruma Hitode which sounds GREAT! Hitode is Japanese for starfish. But What is a "Higuruma"??

    Higuruma is apparently one name for a ghost/yokai called Kasha (whose name apparently translates to "flaming chariot" who carts the corpses of sinners off to the underworld (thanks to Matt Alt for this info). I suppose in this case the "corpses of sinners" are represented by small crustacean prey! Muahaha!

    The resemblance between the flames (the arms) emerging from the wheel  (the disk) is how this starfish was likely named! Pretty neat!
    Image from Dr. Fujita
    To give you a better idea, here is a very similar "fire wheel" type yokai called Wanyudo, which translates to "wheel monk" and who apparently steals the souls of those who gaze upon it. Apparently many yokai can be similar in appearance

    It also shows the "flames from wheel" appearance that this starfish takes after...
    Image via the Yokai Attack! FB group
    Interestingly, Higuruma hitode was actually assigned to a similar species called Novodinia pacifica so perhaps Brisingaster robillardi  should be referred to as a Wanyudo hitode or perhaps a Kashahitode??

    3. The Sazae-oni aka the "Snail Ogre" 栄螺鬼
    This yokai is apparently one of the more malevolent ones and according to is a dangerous spirt that pretends to be a beautiful drowning woman in order to lure and feed on sailors.

    There's a whole mythology about these yokai which involves pirates and monsters biting off their testicles.  You can read the colorful version here. 
    Image by Toriyama Sekien via wikipedia and also this Japanese site
    These yokai are actually based on horned turban snails, Turbo cornutus which look like this
    #791 horned turban (サザエ)
    These snails in Japan are called sazae (hence the name "snail demon"and are eaten throughout Japan, often grilled in their own shell
    Sazae being grilled in IH Cooking Heater

    This species of snail is widely familiar to the Japanese and was even made into a kaiju called Gogo in the show Ultra Q, the precursor to Ultraman!

    4. Hekigani ヘイケガニ The "samurai crabs"(the crab Heikeopsis japonica)
    This "ghost" is actually more of a ghost story. It basically relates the story of this crab, Hekeopsis japonica which often have a very human-like face on their carapace (i.e., the top side of the skeleton).
    Heikegani 日本平家蟹
    This species is referred to as the "samurai crab"?   Why? The "faces" on these crabs (actually the fine morphology of the carapace) have been thought to be the reincarnations of Japanese Heikie warriors defeated at the Battle of Dan-no-ura as told in The Tale of the Heike. Wikipedia has a nice summary of this event.

    But here's a gorgeous painting which shows this event in various stages..
    Image by Utagawa Kuniyoshi via Wikipedia
    This crab species was also made famous by Carl Sagan who discussed them as an example of inadvertent character selection on Cosmos. You can watch this segment here

    4a. The Kani-Oni: DEMON CRAB!! 
    While doing research for this post I came across this creature, the Kani oni! aka the Crab Demon.   I couldn't find out much about it, but I did realize one thing..
     Thereare only THREE pairs of legs per side.  This is a characteristic feature of lithod crabs, which are actually more closely related to hermit crabs. "Proper crabs" such as the Japanese spider crabs have 4 legs on each side. 

    But this species is very similar to this species, Lithodes aequispina (unconfirmed ID). Thus, the ghost crab does seem to be something in the Lithodidae. 
    Golden King Crab (Lithodes aequispina)
    The spines on the crab might allude to another species of lithode crab which has bigger and more prominent spines on the carapace, such as this one.
    Paralithodes camtschaticus 5

    5. The Umibōzu 海坊主
    So this particular ghost isn't actually based on an invertebrate..but it gets honorable mention..

    The name Umibozu translates to "Ocean or Sea, Buddhist Monk" and have been explained as the ghosts of drowned buddhist monks.  They are apparently haunted spirits of the ocean and mentioning their name invokes bad luck for ships at sea.
    From all the accounts that I could find, there are apparently different "morphotypes" of what Umibozu look like with some images looking a bit more of a human shape...

    The Umibozu tend to be rarely seen and considered somewhat mysterious..

    I happened to notice a curious coincidence between these and Opisthoteuthis, aka one of the "dumbo octopuses"! But nah.. the umibozu are FAR more menacing! 


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    Image photographed by Martin Buschenreithner. Borrowed from the US Slug Site! 
    NUDIBRANCHS! Happy First Sea Slug Day!!

    Given its proximity to Halloween and my propensity for sharing cool stuff about weird animals my post this week is about one of my favorite bizarre sea slugs: The ones in the genus Melibe!

    Melibe (in the family Tethyiidae) includes 17 currently recognized species which are known Primarily from the tropical and temperate Pacific but with a minority of species from the Atlantic, including South Africa and the tropical west Atlantic (Bahamas, Florida, etc.)

    Personal caveat: I am not an expert in nudibranchs and have gone with names used by the photographers. If you know better let me know and I will correct them.

    Here's a "classic"Melibe leonina from the California coast to give you an idea of what the general body plan looks like...

    This species is fairly well known. With nice brief write up by Monterey Bay Aquarium but many others as well. 
    Melibe sea slug
    When encountered, some species are often present in great abundance..
    Melibe leonina
    Although they appear to be mostly filter feeding in the pictures
    Hooded Nudibranch
     some Melibe species can also be fairly effective predators.. here's a nice video from Japan showing prey capture..

    Morphology on these animals is remarkable in that their body can be translucent to transparent and the internal anatomy can be visible just like those old "Visible Man" model kits!

    A close up on the lobes on the body reveals these fine branching structures-the digestive glands! Which function in digestion of food
    nudi branchia 1417

    What happens when you take these digestive glands to the extreme? Along with a transparent body?
    You get Melibe colemani, aka the "Phantom Melibe!" named for the photographer Neville Coleman, who was a noteworthy photographer, diver and natural historian from Australia.

    What you are seeing in the picture below is its digestive glands!! The body is completely transparent!! This species was originally described from Malaysia. These images are from Lembeh (Indonesia) and other images have been identified from the Philippines, so I would imagine it occurs in roughly that tropical, central Pacific region. 

    Nudibranch (Melibe Colemani)
    Nudibranch (Melibe Colemani)
    I know just looking at pictures doesn't look like its a sea slug, but check out this video!!
    They SWIM!!
      Most of the species seem to crawl around or stay in one place, but given the motivation, some species can swim.. Here's what I think is Melibe viridis, based on this article in the Sea Slug Forum but kind of swimming in the water column..(identified as Melibe japonica, since synonymized)

    Melibe diversity is fairly mind boggling.

    This one from Lembeh, Indonesia. This one is also identified as Melibe viridis, but which seems to vary somewhat from the one from Japan. These can get quite large with some individuals reaching almost a foot long!

    There's a nice write up on Melibe viridis here on the Slug Site. Here.
    Lembeh_Melibe sp
    Ugly Nudibranch
    Ugly Nudibranch
    Seeing this one alive is almost a necessity!

    Melibe engeli from the Philippines
    Melibe engeli
    Melibe pilosa from the Philippines
    Melibe pilosa.JPG
    Melibe digitata from the Philippines
    Melibe digitata

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    Bonjour and Greetings! My apologies for missing a post last week! I am currently on a research visit at the world famous Museum national d'Histoire naturelle in Paris! Between jet lag and getting my work set up, things got away from me!                                                                                     
    This week, A collection of starfish mouths! Echinoderm anatomy often fascinates people. The symmetry is one reason, but also the very intricate architecture and unusual textures. 

    Here is a collection of close ups and abstracts from echinoderms in the Tokyo Museum.

    Here's an assortment of mouths & mouthparts from the collections of sea stars in Paris! I see the adaptations for survival in these structures.

    Spines serve a protective function in many species but are also part of how the animal feeds. The full range of how these structures function is not clear. In contrast, other mouths are surrounded by granules or plates presenting a somewhat different interpretation.

    but certainly.. these might even evoke more artistic interpretations from others!

    Euretaster, a tropical slime star. Spines galore!
    From Luidia, a multi-rayed sand star
    From the Antarctic Odontaster.. note the big "teeth" on each plate. These are thought to function in sponge predation.
    Protective mouth plates on Lithosoma
    On a tropical oreasterid
    On the sand star, Astropecten
     On a "cushion star"Peltaster placenta
    From the tropical cushion star Culcita novaeguineae
    A deep-sea mud star, Plutonaster
     Deep sea goniasterid, Nymphaster
     A deep-water oreasterid! 

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    This week: more showy echinoderms from one of the greatest museums in the world! Paris! Here's another study in abstracts-focusing mainly on sea urchins!

    Last week was all about starfish mouths & their spines, etc.

    I've blogged before about sea urchins from Paris. Here's one...

    and an older one..

    And a similar type of blog from my visit to the natural history museum in Tokyo! 

    Alien landscapes? Weird colors? Vs. Spines, mouth plates and sea urchin skeleton! Enjoy!

    The duo colored spines of the urchin Salmacis
    The "teeth" of a "pancake urchin"

    Oral spines on this cidaroid urchin. Yikes!
    The naturally orange colored spines of this cidaroid (Compsocidaris?)
    Natural green and purple stripes on these urchin spines!
    More green and purple colors on this cidaroid urchin!
    The large crazy spines of Goniocidaris and what lies beneath! 

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    Greetings! So, today I am en transit from my month long research trip in Paris back to home base in Washington DC!  So, in the meantime I thought I would share the results of this great new imaging project presented in GigaScience by some colleagues at CapeTown University in South Africa whom I met while I was visiting a few months ago!!  Jannes Landschoff, Anton duPlessis and Charlie Griffiths.

    Their study actually surveys THREE species of brooding brittle stars!

    What does this mean? In MOST echinoderms,  following fertilization juveniles pretty much settle out on their own and are left to grow/rear out on their own. But in some unusual instances there is actually parental care! 

    So, yes, some adult echinoderms rear juveniles! Yes! Baby echinoderms! I've detailed this behavior in starfish in some detail here.   and of course, who can forget the life and death struggle of tiny asterinid starfish hermaphrodites who attack and eat one another in the "womb" of the mother?? (here)

    Jannes' study focuses primarily on three brooding species in the South African area, including Amphiura capensis, Amphipholis squamata (both in the Amphiuridae) and one called Ophioderma wahlbergii

    Jannes' work was actually surveyed here in GigaScience's own blog  Jannes and co authors use three dimensional visualization tools, including x-ray micro tomography scans to unobtrusively visualize brooding juveniles without destructively sampling the original specimen. Neato!

    This gives you an idea of what Amphiura capensis looks like..
    Image borrowed from Eastern Cape SCUBA diving! Go check em' out! 
    Here's a visualization with CT Scan from Amphiura capensis!
    which you can see more of here on this video

    Jannes' study images brooding (i.e., the behavior of retaining the juveniles) in cavities called bursae which are located in the regions between the arms within the disk of the animal (in blue)
    Here we have some just SPECTACULAR imagery of brooding in Ophioderma wahlbergii!
    As it turns out, this will probably be a useful tool for non-destructively studying other brooding brittle stars and other echinoderms!

    One South African brooding starfish (different from brittle stars) species which we know almost NOTHING about?? The South African "slime star"Pteraster capensis!  
    Brooding cushion star, Pteraster capensis

    and there are a MANY species of brooding brittle stars to choose from...

    and this aptly named brooding species...Ophiacantha vivipara (from Rafael Martin-Ledo's neat but shortly lived Antarctic blog!)
    Congrats to Jannes & my colleagues at Cape Town University for their new paper and looking forward to hearing more about their interesting future research! 

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    So, for whatever reason, I've been noticing an uptick in the number of reports (and questions from the public) about moribund or otherwise dead starfishes (aka sea stars) being washed up on beaches en masse. 
    to this account of Asterias rubens  from Pensam Beach, New North Wales in the UK,

    And I've seen a host of different reports. Many from the southeast coast of the United States, in the United Kingdom and even from Cape Town, South Africa. 

    I thought I would take a moment to provide what seems to be the MOST likely explanation: During storms, violent or strong water currents pick starfish up off soft sediment bottoms and wash them ashore.

    Different species of starfish in different parts of the world are affected but all share certain commonalities.
    Dead starfish at Budleigh Salterton March 2010
    So here's the thing. As a scientist I've NOT actually seen storm-driven currents pick up hundreds to thousands of starfish and drop them on the beach. My conclusion is based on an assessment of various environmental factors which all point to, what seems to me, a parsimonious conclusion.

    You'll often see a lot of officials and local biologists essentially say the same thing. There are LOTS of these starfish present AFTER a storm. 

    None of them actually saw what happened (and how could they have?) but this seems like an explanation which fits all the facts. 

    Lines of reasoning and evidence pointing to the "storms beach starfish" hypothesis
    • In almost EVERY instance that this has been reported, there have been reports of either storms or high winds. Even if this was not necessarily reported in the news report itself. For example in the case of the Queensland Pentaceraster case, there was a reported storm involving hail the day before!(here
    • Bear in mind that storms don't JUST mean high winds and rough water current. It also means FRESH WATER input. Echinoderms are notoriously intolerant of low salinity/freshwater. Low salinity water might serve to weaken or otherwise just disable enough of them to be washed ashore. 
    • The species in question: Luidia clathrata, Pentaceraster sp., Asterias forbesi, Asterias rubens etc. (and others) are all known to occur on sandy or unconsolidated (i.e. loose sand) sediment bottoms. So its not unreasonable to see how strong water currents associated with inclement weather could serve to pick them up and drop them ashore. These species all tend to occur with rather high abundance so they tend to end up washed ashore in great numbers.
    Some Common questions:

    1. There are SO many dead! Will the starfish population recover?
         Yes. Almost certainly. Although it seems like hundreds to thousands of individuals bear in mind that many of these species occur over a huge area (Luidia clathrata for example occurs throughout the Gulf of Mexico and along the southeastern coast of the United States) and their spawn includes hundreds of millions of individuals.
         A related question to this usually involves "If they survive, shouldn't they be put back?" Unfortunately, its unlikely that most of them have survived by the time they've been found. Would it be good to have them returned to the ocean? Sure. And in fact, the good folks in Fish Hoek Beach in Cape Town, South Africa did just that!! 
    The living starfish  (species: Marthasterias glacialis) were collected and returned to the ocean. From an ecological/population ecology perspective this was probably a trivial event but it says a lot about the people involved. So good on them! 

    2. Based on the news articles, scientists are always BAFFLED! BAFFLED I tells ya'! About this "starfish washing up thing" Why is that??
    So, uh... scientists are not REALLY baffled by these events. Almost every article about starfish washing up on a beach usually involves a scientist providing an explanation for what happened. Usually involving a storm or freshwater input. But as I said before none of them (myself included) actually SAW what happened. And so their explanation is usually filled with qualifiers and caveats that the news media exploits as "SCIENTISTS BAFFLED BY THIS THING THAT HAPPENED!" 
    and of course, there is a.. how shall we say... "sensationalist" element which is used to make the story a bit more appealing to the general populace. 

    But really? It was probably storms stranding them on the beach. 

    3. OH NOES! We recently read about whales/dolphins/jellyfishes being stranded on the beach!! Does this mean the starfish are all dying and beaching themselves on the beach for the same reason??? 

    *sigh* No. No it does not.

    Animals such as whales, dolphins and jellies (jellyfish) all swim in the water column. In the case of animals like jellyfish and/or by the wind-sailors, water currents end up carrying a bunch of them onshore. Its not always clear what beaches whales and dolphins (or if there is a single reason in every case) but in these cases, we have animals that are in constant motion that get stranded based in part on the animals getting there on their own power.  

    Starfish live on the ocean bottom. They get picked up and carried to the beach. Its a localized event tied to something a storm. It would have to be VERY unusual to see some kind of event that would be the sole cause of mortality affecting constantly swimming (i.e., pelagic) animals like dolphins and bottom living invertebrates like sea stars.


    Nope. When starfish succumb to starfish wasting disease (aka starfish wasting syndrome, etc.) they show white lesions and in most cases they disintegrate in place, whether its underwater or in the intertidal or wherever. Image from the UCSC Starfish Wasting Disease Page.

    Currently, Starfish Wasting seems to be primarily centered on the west coast of North America.

    Most of the animals one observes washed up on the beach generally seem to have been in good health.  
    Dead starfish at Budleigh Salterton March 2010
    Dead starfish at Budleigh Salterton March 2010

    Is it possible that infected starfish could begin to appear? Sure. But individuals would need to show lesions or other indications of disease which we have yet to observe. 

    5. OH NOES! ITS TEH End of Days/R'Lyeh is rising and Cthulhu is chasing the starfish out of the sea!!
    If Cthulhu's return caused a massive storm surge, with high velocity wind and water currents and huge storms causing freshwater input to local ecosystems thus resulting in a big low-salinity wave that washed a bunch of starfish onto shore? then... maybe. But otherwise. no. 

    But seriously.. do I continue to be interested in beachings? Sure. Many interesting potential questions. Are we seeing more of these beachings because of climate change-related storms? How seriously do these storms affect the populations of these species? and more importantly their prey? How regularly do they occur?   But let's keep them to normal, localized phenomena and not crazy, "end of the world" death storm events shall we?? 

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    Image taken by Jan Mees. From the World Registry of Marine Species
    This week, a photoessay and odd little facts about this very strikingly colored/decorated oreasterid starfish, Protoreaster lincki!  You can check this past post on how to tell Protoreaster species from the similar Pentaceraster species..

    This is a shallow-water tropical species known primarily from the western Indian Ocean, especially on the east African coast. The species descriptor "lincki" is named for the German naturalist Johann Heinrich Linck, the author of a noted monograph on sea stars, De stellis marinis liber singularis published in 1733. Johann Linck is also the namesake of the familiar starfish genus Linckia. Many years ago I wrote a little bit about where funky starfish names come from before, especially Nardoa and Luidia.
    We really don't know much about the primary biology of this species. Its thought that they feed primarily on microalgal film so presumably they are dependent on the "goo" on sea grass, sea bottoms, etc.  

    This species is fairly easy to recognize due to its striking red on white coloration, but also the very distinctive pattern of spines and etc... There is some variation however. Spines in some individuals are more conical versus others which are more blunt...
    Image taken by Adrian Pingstone 2005 at Bristol Zoo Aquarium, Bristol, England via Wikipedia

    red starfish
    Close up of Starfish (Protoreaster linckii), Kenya.
    red-knobbed starfish (Protoreaster linckii)
    Red, yellow, and grey starfish
    Zanzibar Starfish
    The spines on this species and other oreasterid starfish likely serve against larger predators. Its unclear if they are effective against smaller specialized echinoderm predators such as these harlequin shrimp

    Variation! The skeletal patterns on these sea stars are broadly consistent and distinctive for this species. But in the same way that people can have different hair and skin color, different facial features, etc. starfish show variation in spination, pattern and even color... 

    Here are some examples. Its unclear if the differences are simply random or if they correspond to some kind of environmental factor such as food, etc.

    Red-knobbed star

    Tanzania, African coast.
    Tanzania, African coast.
    Red-knobbed Starfish
    Tanzania, African coast
    Tanzania March 2009 261
    Zanzibar, African coast
    Zanzibar 2005 192 (Large)
    and the occasional 6 armed variant..
    Red star on the beach

    As with the Indo-Pacific species, P. nodosus, this species is fished for the tourist trade. Data about its reproductive abilities and "carrying capacity" for a fishery aren't well documented.
    StarfishStarfish flashers

    ART! For some odd reason, this species has also served as the inspiration for many distinct types of art. This postage stamp...for Mozambique in 1982 and the more recent rendition below it, including the pastel and of course TATTOOS! 
    via the World Registry of Marine Species

    Starfish by CreativeCurseKina on DeviantArt

    starfish tattoo by SunofKyuss on DeviantArt

    Happy Holidays from the Echinoblog!

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    So, I don't normally do these "end of the year" recaps, but man, 2015 was BUSY.  I travelled to three continents, described a NEW FAMILY of starfish in addition to all the other stuff.. Here are highlights....

    1. JAPAN part TWO! 
    Starting at the end of January I returned to study at Japan's world famous National Museum of Nature and Science in Tsukuba, Japan (outside Tokyo). Among the many cool adventures:

    One such interesting starfish was Trophodiscus! The starfish which broods babies on the disk surface! 
    2. Someone made one of my starfish into a TOY! 

    A video of the set is here.. My contribution is at the end..

    3. I described a NEW FAMILY, genus and two new species of sea stars! The first hydrothermal starfish Paulasterias

    Named for deep-sea biologist Paul Tyler, the type species is the first to be found living in association with hydrothermal vent habitats.
    The second species, occurs in the North Pacific and is named for my colleague Dr. Craig McClain at Deep-Sea News and was collected during an expedition which I was present on due to Craig's invitation! Scientific collaboration in action! 

    4. I visited and have studied at the Iziko Museum in Cape Town South Africa!

    One of my most memorable trips was from April-May when I visited the Iziko Museum in Cape Town, South Africa!! Thanks to a collaboration with Dr. Lara Atkinson from their marine environmental organization, SAEON (the South African Environmental Observation Network) I was able to visit their marine invertebrates collection and study the collections.

    This was a VERY frutiful visit. I identified nearly 700 specimens, and discovered several rarely seen species as well as working with the the citizen science community to ID species seen by divers and naturalists.

    Here were some images from the trip... one of the South African Museum's specimen catalogs and Candice one of the curatorial techs holding a specimen of Hymenaster! A specimen of a deep-sea slime star which had been sitting undiscovered for some 40 years! 

    My thanks to Lara and the staff at the Iziko Museum including curator Wayne Florence and collections personnel Liz and Candice for a GREAT visit! 

    5. Described new Deep-sea starfish which feed on corals
    So, I described several new species this year..but for some reason a bunch of them feed on deep-sea corals.. Here's a post where I talk about a new paper describing new Hawaiian species.. Some of which I saw later on when Okeanos investigated the Hawaiian Islands!

    6. I provided my usual narrative and information to Okeanos Explorer in Puerto Rico and Hawaii! 
    For the last few years I've participated as part of the "shoreside" talent pool which Okeanos calls upon to assist with identifications and questions about sea stars and echinoderms. 

    I also take screengrabs of the live feed and post highlights. This year, Okeanos travelled from the tropical Atlantic, working off Puerto Rico, travelling across the canal to the North Pacific where they worked in the Hawaiian Islands!!

    Perhaps one of my proudest moments from the Puerto Rican expedition was being able to identify this rarely seen solasterid starfish, Laetmaster spectabilis from the abyss of the tropical Atlantic!

    This species had been collected once in the 19th Century and not been seen again until the Okeanos Oceano Profundo expedition! Here's a recap post from that week. 

    When Okeanos Explorer reached the Hawaiian Islands we saw some species that I described back in 2006. This for example, was Circeaster arandae, which was known originally from Madagascar and New Caledonia. Now we know it lives in the Hawaiian Islands! 

    Its a weird feeling to have described something like this from preserved specimens and then to seem them alive like this..
    and we saw some weird critters like this, which were probably new but remained a mystery...

    We also saw a LOT of glass sponges.(go here)

    Stalked crinoids, benthic ctenophores and enormous sponges! (go here)

    7. Took a little break for the first INTERNATIONAL POLYCHAETE DAY! on July 1st! 
    In honor of Dr. Kristian Fauchald, curator of polychaete worms at the Smithsonian's NMNH, who passed away on April 5, 2015. This year we celebrated the very first International Polychaete Day on Kristian's birthday. 
    Polychaete worm
    Here is the Storify if you missed it! 

    8. Then I helped launch SEA SLUG DAY!! 
    This event was similar to International Polychaete Day except that it celebrated the very much alive, Dr. Terry Gosliner at the California Academy of Sciences. The world's foremost authority on nudibranchs and their kin.  Sea Slug Day was appropriately enough held on October 29th, his brithday the Friday before Halloween! 
    Goniobranchus roboi
    Here is the Storify if you missed it! 

    9. Studied Deep-sea Starfish at the Paris Museum in November! 
    I've been visiting Paris for several years now and so, the trip has become almost routine. I'm usually there for about a month working on new species from exotic Pacific and Indian Ocean locales collected by French museum scientists.

    I even worked some Cretaceous (fossil) starfish into the visit this time around. Hopefully by next year you will be seeing some of the new species published and publicized here!

    10. And last but not least.. I topped 3000 Twitter followers! My thanks to all of you!!
    My ongoing efforts at education and outreach would not be possible without YOU!!! 
    Its good to know that what I produce is read and of interest. Twitter has given me a more regular way to share..but the blog remains appropriate for "long form" stories...

    Thanks to everyone who follows! 

    For those who are interested, I actually try to keep track of my new species on this post. It shows images of each! (its a little behind at the moment..but soon!)

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    Picture by Robert F. Bolland from the Okinawa Slug site
    Happy 2016! And a fine one it has been so far! I'm on my annual holiday travel to San Francisco visiting friends, family and my colleagues at the California Academy of Sciences..

    During this visit, Curator Bart Shepherd, a colleague of many years from our days at Steinhart Aquarium indulged me in showing off this recent collection from the Academy's scientific expedition to the Philippines: the benthic ctenophore Lyrocteis! Possibly Lyrocteis imperatoris..
    These are inspiring animals. They're not only big (about four to 6 inches tall) but they are also WEIRD things that nobody (other than scientists) ever gets to see, but now? thanks to social media and some excellent aquarium science.... these mysterious animals may actually get some time in the sun!  This aquarium in Japan has actually be able to breed them

    I have described and mentioned benthic or "bottom" ctenophores (= comb jellies) before (and recently! see here).

    Long story short: Most comb jellies are midwater (=pelagic) swimming gelatinous animals... but SOME of them are unusual in that they have adapted to living on the sea bottom.. Some live on sea stars, while others on coral. 

    Today I thought I'd just focus on this one genus: Lyrocteis the only member of the family Lyrocteidae. Lyrocteis includes two species, one from the Antarctic and one from the tropical Pacific.
    The name apparently refers to its resemblance to a Lyre. (think of the root word of "lyric" which means "of or for the lyre") Neat, eh?  and "cteis" which refers to the comb rows present in all "comb jellies"

    There's not a lot known about them. They feed (see below) in a manner similar to the swimming species using long tentacles to capture food. When described in 1941 (here), they were labelled as "sessile" but the Antarctic species was described as being able to move 1 to 2 meters per day (here to see)

    Here's an individual identified as the Antarctic species: Lyrocteis flavopallidus
    2.... and the other one?
    and there's a second species known from throughout the tropical Pacific called Lyrocteis imperatoris, described in 1941 by Professor Taku Komai at Kyoto Imperial University to honor Emperor Showa of Japan. The original specimen was apparently collected from Sagami Bay by the Biological Laboratory of the Imperial Palace. He described it as a "strange marine animal.."

    This species is described mainly from the tropical Pacific. Possibly the Indian Ocean I suppose (based on the ones below) but none are known from the Atlantic.  Most of these live in relatively deep-water, at the lower edge of SCUBA depth to significant depths in the deep-sea (>500 m).

    Its name in Japanese: 
    kotokurage コトクラゲ

    Here's the species we saw in the Hawaiian Islands during the Okeanos Explorer cruises in September. In theory.. there are only two species.. the Antarctic one and the tropical Pacific species.
    So, this is possibly Lyrocteis imperatoris.. but exact details remain elusive.  A great MANY different color variations have been observed in observed specimens of Lyrocteis.. This makes biologists wonder if they are seeing multiple species??? Or perhaps one species with a lot of color variation??Dr. Komai, the scientist who described this species noted a great variation in color when originally collected.

    Its possible (and even likely) that there is more diversity (i.e., more species) but the animals don't make it easy to study them.

    Why? Because they aren't seen frequently and when they do, collecting is difficult. The individuals
    aren't easy to sample and for whatever reasons, the body of these animals is extremely difficult to intact specimens aren't generally available to study...

    Here were some spectacular red ones from Okinawa..
    Bart Shepherd & the California Academy of Sciences Expedition to the Philippines encountered THREE color forms... the speckled one above and two others: a purple/red one and a yellow one...

    and here's a South African species in the Indian Ocean. Another color and puffier..

    One of the nice things about our modern age is that video and image observations have become easy and of high quality

    If you have Facebook, here's a feeding video of the Lyrocteis collected by Steinhart Aquarium from the Philippines..

    Here's one of the purple south African species observed via video with its feeding tentacles extended...

    Here's a nice one of a Japanese species with tentacles extended... from SHINKAYABLOG which translates to "deepsea" blog  This is basically similar to the way that swimming comb jellies feed...
    This also explains the kawaii (cartoon mascot) for Lyrocteis imperatoris!   Note the feeding tetnacles catching the fish!!
    from @deepsealife

    Amazingly, someone is SO fond of these that they have made tiny magnets out of them!
    3. The Story About its original discovery!!?
    Dr. Komai, in his 1941 description of this species recounts an interesting story about "when" this species was discovered. Because apparently, although he described it in 1941.. he was NOT the first one to have encountered it!!
    What makes the story of the discovery of this remarkable ctenophore more interesting is the fact that another specimen of evidently this form had been obtained previously from the same Sagami Bay and recorded by a Japanese zoologist, but without any idea of its real nature.... August, 1896, we find a short note in Japanese by T. N. (obviously Tokichi Nishikawa, the inventor of the famous cultured pearl) entitled " A curious animal" with rather good illustrations, one of which is reproduced in Fig. 3. The accounts and figures clearly show that the 'curious animal' was no other than a specimen of the present platyctenid.
    Nobody who saw The real nature of this form clear forty-five years later. T. Komai. it could tell at that time what thus remained enigmatic only to be made clear forty-five years later."
    ..and don't worry, I haven't given up echinoderms! But travelling makes you appreciate opportunistic topics!! 

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    image by Jonathan Martin
    So, my apologies for the delay between my last post and this one. Between traveling from the west coast, the blizzard and my laptop experiencing..."difficulty" I've missed one or two posts... But! here's what I have been up to...

    So about two weeks ago I was in Seattle at the Sea Star Wasting Summit, hosted by the Seattle Aquarium!

    This was an informal gathering of about 35-40 people who work on the west coast of North America, ranging from Alaska to Southern California to report on various aspects of Sea Star Wasting Disease (aka Starfish Wasting Disease aka Starfish/Seastar Wasting Syndrome).
    The meeting brought together folks from a broad range of occupations that all have had some experience or contribution to our knowledge of the Starfish Wasting Disease phenomena: pathologists, veterinarians, ecologists, citizen scientists, aquarists, taxonomists, educators, and etc..
    So, while I can't repeat everything that was discussed (some of it was still unpublished) here are some further insights...

    What do we know?
    1. Who? The disease seems to affect sea stars in the family Asteriidae most acutely. This includes Pycnopodia helianthoides (aka sunflower star), Pisaster spp (esp. P. ochraceus-the Ochre star), Evasterias troscheli (mottled stars) and Orthasterias koehleri (rainbow stars). Pycnopodia helianthoides, the sunflower star seems to have been one of the hardest hit...
    Image by Jonathan Martin

    but ultimately the disease seems to affect nearly every shallow-water seastar species on the Pacific west coast. So that includes leather stars (Dermasterias), Bat stars (Patiria), sun stars (Solaster) and so on...

    There were a few species which showed much lower incidence of being infected but its unclear if that's simply an artefact (i.e. they aren't seen that often to begin with), less vulnerable, but there is really no further data...
    Image from this article in Vice:
    2. Where?The disease, as part of the larger event starting in 2008 is now known from southern Alaska, British Columbia, Washington, and Oregon down to Southern California (and apparently Baja California).
    map from
    At the moment, almost all of our observations are from intertidal/subtidal observations. Nothing really substantial from "deeper" water...

    There is another "die off" event on the east coast but it has not been as thoroughly evaluated, so not sure.  This 2012/2013 blog by Elena Suglia documents some of this phenomena 

    3. What? Symptoms of the disease of course are widely known and have been outlined in detail here at the UCSC Seastar Wasting page. The disease begins with white lesions and tissue necrosis (as shown below) and leads to "wasting" or "melting" of the body into an ugly pool of tissue and ossicles... But there's MUCH more to be seen at in terms of characterization, etc. 

    There's a whole bunch of observations of these symptoms all over the internet Both from my prior blogs: Pycnopodia die off, and a further account here..  and many, MANY accounts of starfish wasting disease from Allison Gong's blog.

    But, one important new clue: The Gonads! One of the interesting details which Ian Hewson reported at the SSW Symposium (link here) which was further reported in the news was this bit: the gonads in infected sea stars are often inflamed with tissues sometimes extruding from the gonopores (the openings through which the gametes are emitted). Note the white blobby bit between the arms of the purple Evasterias troscheli (mottled star) in the picture below...
    image by Allison Gong
    A further important consideration is that gonads and reproduction are tied to activity during certain times of the year as temperature fluctuates. This might also be an important consideration.

    This is will likely be important in piecing together the actual cause of how the disease actually kills the sea stars, which remains poorly understood.

    Challenges: figuring out what causes the disease is difficult and remains elusive.
    So, by now many people have likely seen Ian Hewson et al.'s (2015) article showing identification of the Sea Star associated Densovirus (SSaDV) with the disease. Popularly reported here and in other news outlets..

    This was an important first step. But its important to realize that we still do NOT KNOW that this is the actual CAUSE of the disease. 
    Sea star with (likely) wasting syndrome
    Probably one of the most important lessons I  picked up from the meeting was how careful the work of disease pathologists needs to be. 

    Correlation is NOT Causation! 
    Powerful genetic tools have allowed us to characterize the SSaDV virus and experiments show that it is ASSOCIATED with the disease. But we have yet to identify exactly HOW Starfish Wasting Disease actually works. In other words, what actually happens to the animal to initiate death?

    Just because we have this "disease associate" does not actually mean that it causes the disease.. it could simply be present with the disease as part of the suite of entities (e.g., bacteria, protists, etc.) taking advantage of the sick animals. Or it could be something already present that has become fouled or modified by some other factor.

    My take away message was that MULTIPLE lines of evidence (genetics, tissue analysis, external observations, etc.)  should all converge on the same conclusion. In other cases, pathologists are able to actually observe the agent (virus, bacteria, etc.) perform whatever action it takes to create the disease and thus the symptoms..

    At this point, we are still working on what actually causes the "wasting symptoms" to occur. This is not to say we are clueless about it..but a definitive cause has not been shown.

    One of the biggest issues we have right now? Understanding starfish biology.
         A LOT of the study of invertebrate physiology went "out of style" in the 1960s along with a bunch of natural history research. There are many instances when we just don't understand what "normal" is for sea stars (or their relatives for that matter).

    And so..the other powerful tool at play? Careful critical thinking..

    (and yes.. what this means in the real world is that NO zombie or science fiction disease movie is likely EVER going to be solved in two hours!!)

    What Tools are being used?
       So now that I just got done saying a whole bunch of stuff about care and critical thinking, that is NOT to say that scientists are not throwing a whole arsenal of scientific tools at this problem to try and obtain as many different types of data as they can!

    Dr. Felicia Nutter and student Eric Littman at Cornell University for example utilized sophisticated imaging techniques ranging from traditional X-rays to CT scans in order to look at the endoskeleton in afflicted sea stars, which it was thought, might be showing decreased skeletal density.
    Image from
    Other tools include the Illumina technology sequencer which was used to investigate the phylogenomics of the virus and other microbes present in diseased individuals. Long story short: Tissue are taken from infected animals, recover DNA (or RNA) is extracted and purified, these machines sequence it (i.e., analyze it), and this permits identification of the organisms present. This was how the SSaDV (the sea star virus) was identified and characterized...along with the many other bacteria and other ambient forms living in/on the sampled sea stars..

    These are among the many types of tools being applied..but there are certainly many more that fall into the more traditional roles: taking tissue samples, aquaria and freezers for living animals and tissue specimens

    But as mentioned above, all roads should lead to Rome.. and with any luck, the results from these studies should all be consistent with one another...

    Are there/Will there be Ecological Effects??
    So, although a LOT of the attention both public and scientific is on the disease itself, many folks often forget that the after effects of the disease will also be very significant!

    Sea stars such as Pisaster ochraceus and Pycnopodia helianthoides occupy very important roles in marine ecosystems. Called keystone species, their presence and/or absence as predators is thought to have a HUGE effect on the organisms around them.. (I wrote up a little of this on Pisasterhere)

    So what happens when those predators are suddenly gone??

    sea star shortage
    There were no rigorous and statistical cases showing a clear "cause-effect" loss-of-predator-leads-to-increased-prey data presented. But in many cases there were anecdotal observations that "trophic cascades" might be starting... This one for example, allege that there has definitely been a shift in abundance of prey species..such as sea urchins as mussels.

    That basically means that the loss of a predator triggers an increase in prey (here was an earlier blog post about urchin barrens).  
    Purple Urchins

    which then results in some other ecological effects in the ecosystem.. say, a decrease in kelp coverage (resulting from urchin overfeeding) which in turn results in the loss of kelp-inhabiting species and so forth and so on....

    Some scientific observations suggest that we might be seeing some of this.. but not necessarily everywhere.  Environments across the coast vary.... so what you see in some parts of California might NOT be the same situation in some protected cover in Oregon....

    Time, further data and experiments will tell..

    Other Miscellaneous Questions! 

    1. Are all the starfish on the coast extinct?   Is my favorite species (e.g., Pycnopida, Pisaster, etc.) extinct?? 
    In NO instance is ANY of the species surveyed thought to be completely extinct. Some individuals and news agencies have either misreported or exaggerated the the impact of the disease. MANY populations have been decimated. Localized populations have been wiped out...but there STILL are healthy populations of all afflicted sea stars species.

    So, some species are "locally extinct" which means that you might not see any at your favorite local rock pool or pier but there's no evidence for complete and total extinction.

    2. What about the juveniles we are seeing? 
    There are many reports (such as this one in Nat Geo and this one in the OregonLive) of smaller individuals of various species, Pisaster, Pycnopodia, etc. being seen widely along the west coast where adult starfishes have been wiped out by SSWD.

    There were MANY reports of these out in the intertidal zones along the coast. The significance of the juveniles is unclear at this point.   Possible reasons and questions as to why we are seeing them:
    • They are now more obvious because the adults are gone (and we are looking)
    • They have become more bold because the adults are gone.
    • Are there more of them present now because of absent adults? 
    • How fast do they grow? Will they enter in the former adults ecological setting?
    Sadly, there HAVE been reports that small individuals can contract the disease. But they don't all seem to have it. So what's going on?? This whole dynamic involving juvenile species remains poorly understood.

    If you see any, you can report them to the Seastar Wasting Website here.

    You can download a nifty GUIDE to identifying tiny juvenile sea stars HERE.

    3. Is the worst over?   
    Yes. It seems to be, but mainly because most of the adults which carried the disease are themselves all gone. Its unclear what factors are at play insofar as why some populations have been more heavily hit than others.

    4. Do Any of the standard aquarium antibiotics work? 
    Many of the standard aquarium drugs (antibiotics, etc.) seem to be most effective against the secondary bacterial infections which attack the animals after becoming sick. But unfortunately, they don't seem to curtail the actual disease much if at all.

    5. Is Climate Change/Temperature a factor? 
    I would say yes. And others would agree with me (here). There have been several informal experiments and observations of seasonality which suggest that higher water temperature is, at least, significant and worth investigating as a factor. But, at the time of this writing, a clear paper has not been published which establishes a rigorous link.

    6. Is the wasting disease caused by Fukushima/Republicans/Democrats/Cthulhu/Extraterrestrials/ Atlantis/Inner dimensional beings from the 7th Parallel? 
    Nope. Not even a little.

    My thanks to Lesanna Lahner, Ian Hewson, Melissa Miner and the other participants at the Sea Star Wasting Symposium!

    Standard caveat: i've done my best to represent a LOT of information. Any mistakes are my own.

    Further Resources:
    The Sea Star Wasting Site at UCSC:

    Ian Hewson's blog about SeaStar Microbial Ecology:

    iNaturalist: Tracking Sea Star Wasting Disease:

    A useful summary page from Sanctuary Integrated Monitoring Network (SIMoN)

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    Urchin hearts
    So, yes, that most dreaded of days, Valentine's Day is around the corner! What better echinoderm though to celebrate a day about affairs of the heart then HEART urchins!
    Yes urchins, that are shaped LIKE hearts and will burrow their way into yours!!

    Heart urchins are in fact what's called "irregular urchins", a subgroup known as spatangoids.. These are sea urchins which DIG into sediments. They are closely related to sand dollars (both of them are considered "irregular urchins"). I've discussed this in detail hereSpines and jaws in these animals are specific adaptations for this life mode.
    Loveniidae>Breynia desorii Heart Urchin DSCF1788

    I've actually written about one of the better known heart urchins, Echinocardiumhere.  Note the name of that genus, Echinocardium which breaks down into its root words Echino for "spiny" and -cardium for "heart."

    As I've discussed elsewhere, heart urchins live primarily in sandy or sediment-type bottoms. They occur widely around the world and although most people don't immediately recognize them, they are pretty diverse, about 18 families with many, MANY living species and even more fossils...

    They even go by many, many colorful common names "sea potato", "sea eggs", "sea hedgehogs", etc.

    When people think of sea urchins, they usually think "spiny ball" and heart urchins are no different! BUT they have urchins that are modified as part of their life style to burrowing/digging through sediment..(as we'll see)

    SOME species, such as this Lovenia (top) and the Eurypatagus(?) below have very long and pointy spines most of which you'll notice, are all directed backwards. They would otherwise seem rather ungainly for digging..but these live in shallow-water habitats and the spines, sort of akin to those of a porcupine, seem to aid the animal as defenses... 

    Elongate heart urchin

    But the spines can also be used to aid in movement and these urchins move quickly when they want to...
    Here's five reasons why, you should LOVE heart urchins!

    5. They Dig into and eat sediment!
    Let's face it, heart urchins are frakkin' adorable. They look like little underwater moles! Here's a nice cartoon of how they live.. basically they love being buried under the sediment/sand and stick their tube feet up out of the top to respire and so forth..
    From Nichols 1959
    But why show you a diagram when you can  JUST WATCH IT!!

    Check out these cool videos of various heart urchin species from Japan and elsewhere... the one with long spines looks like Lovenia..but there's a couple of species and these are found in all of the world's oceans! Southern (Antarctic), Arctic, Atlantic, Indian Ocean, and the Pacific...

    4. Bioturbation is important
    You don't often SEE heart urchins that often, but that doesn't mean they are unimportant. They are fairly significant bioturbators! i.e. animals that dig through, aerate and mix up the sediment!

    NIWA's Drew Lohrer wrote this really nice summary(2003) of the importance of the heart urchin Echinocardium and their primary impact: bioturbation.

    Basically, animals that live in sediment, DIG. And their digging imparts an important biological impact: This distributes nutrients, mixes up the sediment allowing oxygen to be transported around, basically leaving the sediment in a place where OTHER animals would be able to use it. 

    Here's is Lohrer's simple but lovely diagram showing how this works...
    3. Heart Urchins were around during the time of the dinosaurs! 
    As a result of the heart urchin habitat (being buried or mostly so), their skeletons are favorably inclined to be buried and preserved as fossils.

    So, heart urchins occur as far back as the JURASSIC with rich faunas in the Cretaceous. So yes, while big reptiles like Tyrannosaurus and etc. were running around on land? Heart urchins and their relatives were digging and moving around on the seafloor during that SAME time period!!

    Heart urchin fossils are VERY informative in the fossil record and a useful model animal for understanding extinction, macroevolution and rates of evolution during that time period. 
    1. Environmental Indicators!
    So, you want to know how animals with "academic interest" have a practical use??  Well, as it turns out Japanese heart urchins, including Spatangus leutkeni, Brisaster latifrons and Echinocardium cordatum were among three species used as indicator species to detect Cesium in and around Fukushima! 

    These were only a few indicator species of course, the others including sea cucumbers and polychaete worms. BUT these are all part of the infauna..that is the animals which live in the sediment and digest the organic materials from the mud and so forth. 

    Many infaunal echinoderms were used as part of this, apparently as yet, unpublished study...

    Extra! REPRODUCTION! Massive aggregations & spawning video!
    And of course, there's SEX. I wrote, wonderingly, about the massive reproductive aggregations of Maretiahere. I still don't know much more about it. 

    Here's a cool video of a heart urchin from Bonaire. So on that note, Happy Valentine's Day if that's your jazz... 

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    You know what I find relaxing? Sea cucumbers. Specifically watching sea cucumbers just moving along wherever they happen to be and slowly and methodically digesting food from off the bottom of the ocean..

    There is a real.. peace from watching them. Slow. Confident. Unworried. Sea pigs and other sea cucumbers... all with their benthic detrital serenity. Its soothing really.
    Today: a little gallery showing some nice closeups to ease that tired day today!

    Sea cucumbers are versatile creatures. Some species can actually feed with filter feeding apparatus inside their anus  (shown below). If you're not feeding from the front there's always the other end...
    Sea Cucumber Anus
    Here's the business end: the mouth on some glass, picking tiny detrital food off the surface. Although "scavenger" and "detritivore" doesn't sound very glamorous, it turns out that this serves a vital function to ecosystems in both shallow and deep-sea ecosystems (see the secrets of sea cucumber poop here! )  Sediment is aerated and "turned over" and doesn't just build up anoxic organics... etc.

    here is where it all starts!

    Some nice video of a Japanese species showing aforementioned feeding tentacles which are used to pick food off the substratum 

    Several more species with their feathery feeding arms extended..

    Here's a nice one showing one of the feeding arms with food being moved INTO the mouth...

    and here...
    Power feeder (Pseudocolochirus violaceus)
    and let us end with one of the most beautifully shot sea cucumber feeding videos!! Taken by "liquidguru"! 

    Lembeh Magnum Sea Cucumber from liquidguru on Vimeo.

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    OKEANOS Explorer is BACK!!! And even though they've only been able to venture into the field for two days, there's already some AWESOME video which inspires this week's post!! 

    Sunday, the ROV spied this awesome beast, a weird sea urchin in the genus Aspidodiadema. Although there's at least one species known in this area, A. hawaiiensis, I'm not sure that this is the same thing.

    I've talked about this urchin before.  The spines bow out from the central body and touch the bottom rather than simply projecting outward as they do in other species. They are unusual in that they use their spines to "walk" along the sea bottom.

    Here's a diagram of another species but with the "walking tips" clearly deployed on the bottom

    On Sunday, they spied ANOTHER Aspidodiadema sp. But the video actually captured the unusual TIPS of the walking spines!!!
    Do you see those round, circular tips that are on the tips of the spines??

    Look at the red arrows below pointing to the "walking cups" on the spines that the urchin uses to move!
    What's also kind of interesting is that this animal (and I think a few others) were actually CLIMBING a rock face and not just walking along a flat surface as diagrammed by Mortensen back in the day. So, these do a lot more than just just support..

    Think of the spines like the long legs on the spider robot from Johnny Quest!

    The "walking tips" of the spines look sort of like little hooves that the spines use to gain purchase on the substrate probably in conjunction with the tube feet. The center illustration shows what the bottom of that "hoof" looks like as you look directly up into it.. basically a modified spine tip adapted to aid in movement!

    So, we HAVE seen something like this before in  Echinothuriid or "tam o shanter" or "pancake" urchins! 

    I've done this story more than a few times..with one of the most recent accounts here.

    Long story short: The urchin walks on a bunch of little legs with modified tips that ALSO resemble hooves! 

    Look for the little white tips on the spines around the bottom edge!! Those are how it moves around on the soft-muddy substrate.
    Spiny sea urchin
    Sea Urchin underbelly
    Here's a close up of what those look like!!! Superficially similar to the ones in Aspidodiadema!  At least in shape..
    But wait.. There's MORE????   How about in STARFISH???
    That's right! I'm pretty sure I've found spines that might serve in a similar (or maybe opposite?) fashion in deep-sea sea stars!  The filter-feeding Brisingids!! (here)

    I just published a paper last year which documents some work I did recently on Hawaiian brisingids!
    The starfish actually live on old munitions and junky metal debris.. I wrote about it here

    The species was named Brisingenes margoae in honor of Dr. Margo Edwards at the University of Hawaii! She is a professor of geophysics working on mapping this unusual munitions filled terrain! 

    She was head of the project and invited my participation! 
    After collecting these starfish I noted something rather interesting.. the tips of the spines that occur on along the tube foot grooves were stained brown from contact with the metal casings they were sitting on! 

    The one on the right shows the brown tip on one spine..
     This suggested that these were actually inset or even anchored into the surface rather than just kind of pointing away as has been suggested from watching them filter feed..

    But when you look further at some other species, you see that there's probably an additional way for them to remains stabilized on whatever bottom they happen to be sitting on..
    Here's a close up of some of those spines in one species from the North Pacific.. The tips are kind of wide and hoof-like! Similar to what you see in Aspidodiadema and the echinothuriid urchins! 
    The case for the functioning of these spines is still sort of at the "hypothesis" stage at the moment..but it seems like a good argument all things considered. It seems likely that they serve at least in part as anchors. But do they use them to move also? Little walking legs? Something in between? Do they vary depending on where they live?

    This all makes sense though. Spines are how these animals interact with their environment. In these deep-sea habitats where you have a lot of water currents and unstable bottoms, these spines help them. Either as support or to help move efficiently where a soft tube foot might not.

    Weird. But I love figuring out strange sh*t like this!!

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    Another week and another bunch of deep-sea Okeanos dives in the French Frigate/Hawaiian Islands region!

    One thing I noticed while reviewing the recent dives and those from last year was just how much COLOR you see in the deep-sea.. black, white, ORANGE... and purple!

    Purple is of course, the color of kings! In Chinese painting, purple represents the harmony of the universe because it mixes red and blue. There's a whole bunch of meaning which you can find on Wikipedia..

    Functional explanations for animals with black, white (such as this Henricia) or transparent/translucent body walls seem to be explained pretty readily by light-related/lack of pigment type explanations.
    And even the bright orange colors in species are considered adaptive.. as orange/red does not reach into the depths, rending animals these bright colors effectively black.
    It is interesting then, what about those animals that AREN'T any of these colors??

    Why are SO MANY deep-sea animals purple?  

    I'm not sure if I'm missing some biophysical explanation.. whether this color has some adaptive significance? Or perhaps simply results in some modification of pigments due to some physiological/defensive/efficiency?? 

    Purple (or at least a bold blue) seems to be present in several different phyla of animals in the Hawaiian deeps as observed by the Okeanos Explorer ROV..  Note: These are all pretty deep. 1000-4000 m or thereabouts..

    How many purple invertebrates are there??

    1. There's this big echinothuriid urchin, Tromikosoma As discussed last week, these walk around on the deep-sea floor with spines modified into walking legs.

    The shallow water relatives of these urchins are VERY poisonous and brilliantly colorful! As presented here, a few years ago.

    Curiously, another purple echinoderm is this feather star (crinoid), Sarametra triserialis (Zenometridae) as ID by Chuck Messing. 

    This "slime star", Hymenaster sp.As has been mentioned before, these are big blobby pillow shaped starfish that emit a noxious mucus when annoyed..
    Here is a violet/purple euryalid ophiuroid aka a "serpent star"...

    But echinoderms aren't the only purple animals down there! 

    We've also observed this squat lobster (Crustacea) on several occasions.. Possibly a new species! (I believe they said it was a chirostylid?) 

     Gorgeous and with a very striking color against the otherwise grey and dark deep-sea bottoms! 

    In the phylum Cnidaria we have....

    There was this dark blue/purple sea anemone! I believe this was a cerianthid? 

    AND this handsome soft coral, Clavularia!
    and this very interesting purple coral (apparently a "proper" coral, a scleractinian)

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    TAXONOMY DAY will soon be upon us!  On March 19th Several years ago, biologist Terry McGlynn declared a DAY FOR APPRECIATING TAXONOMISTS! who had supported his work.

    In Biology, Taxonomists are those scientists who IDENTIFY species and work towards classifying and understanding their evolution and "place" in the natural world. Which species is it? The common one? The one we eat? The poisonous one?? 

    Much of our understanding of ecosystems and conservation STARTS with knowing which species is which! 

    I recently discovered that the  NSF program funding for "Biological Infrastrucutre" aka.. natural history collections has been put on "hiatus" as of this month while it is "being evaluated for the long term resource needs and research priorities in the Biological Sciences Directorate."

    If you have FEEDBACK to the "evaluation" for NSF's Collection in Support of Biological Research, please send email to them on the email address located here:

    So, I don't know anything about the issues surrounding this hiatus BUT I thought that this year for TAXONOMY DAY, it would be a GOOD time to refresh the public as to what services natural history collections perform for both the scientific and "greater good" of society...

    As I described in one of my last posts, the Natural History Museum is essentially THE HABITAT for the taxonomist (as well as many other scientists!)

    1. Specimen libraries that help us ID and understand biodiversity

    Most people don't realize that behind the exhibit floors of dinosaurs, shells, minerals and other awesome displays there are actually large collections of natural history artifacts- shells, plants, insects, skeletons, and many more specimens of different organisms and mineral specimens from all over the world. Some local, some from very far away.

    Just to be clear, these aren't just "stored" to get them out of the way, these specimens are ACTIVELY STUDIED and researched by scientists all around the world. I would say that this is the primary function of natural history museums. They house and care for biological (and in some cases geological and cultural) specimens that serve the scientific community.

    Collections like this one are RESEARCH centers for these kinds of natural artifacts. In the context of biology, if you want to know what some Antarctic fanged rotifer looks like? Find the museum with all the Antarctic rotifer specimens and compare yours with professionally identified one in the collection!

    If you think you have some kind of fossil that you'd like to check as being from specific stratum of rock? Compare it against the one in the natural history collection!

    At one of the museums' I've worked at, they actually have a representative of EVERY phylum of animal! So yeah, you wanna know what a loriciferan is? And finding one isn't convenient? You can go look it up and find it!

    Identifying animals, plants, minerals, etc. aka "collection based research" has all sorts of pragmatic applications (note all of these are based on REAL cases):
    • Identifying economically important pests or invasive species
    • Long term environmental monitoring (such as this one in the Gulf of Mexico)
    • Identifying species used in medical research
    • Identifying species with direct economic importance (i.e. corals or shells for jewelry)
    • Geochemical analysis to study past environments
    • Identify toxic/poisonous/venomous species
    • Identifying bird feathers involved in airplane accidents
    • and of COURSE my favorite application of museum research collections: Identifying weird bugs from a crime scene to help locate a murderer! 
    Natural history collections and museums are thus part of our "knowledge infrastructure." It is here that we begin to identify many of the organisms around us.. be they animal, plant, fungus, mineral...or "other"..

    What makes Natural history collections so critical to taxonomy? This is frequently where  the vouchers or TYPE COLLECTIONS are deposited.
    These are specimens that are the original material used by scientists to describe new species. As I've described earlier, these are sort of the "first issue" of a new species. Essentially the voucher showing the original "intent" or concept of a species by its original author

    These type specimens are kept for collections of all sorts of plants, animals and fossils in natural history museums all around the world. They allow scientists and other researchers sometimes HUNDREDS of YEARS down the road to confirm what a particular species looked like based on a particular author's description..

    Sometimes, this preserved material also retains useful DNA for subsequent extraction and study to understand ancient relationships or other study areas.

    2. New Species are Described from Natural History Collections
    So, if you remember from the recent Okeanos Explorer dives to the Hawaiian Islands, we saw on several occasions, THIS starfish species. A goniasterid, called Circeaster arandae, was a species I described in 2006! 
    BUT When I found it, it was this. A dry specimen that had been sitting on a museum shelf for about 30 years with only a few collection notes. As I've mentioned in prior blog posts, it takes an average of about 21 years for a specimen to go from "shelf" to published description!!

    And that doesn't count the time it takes to reach the "shelf"!! Thus, the museum collection plays one critical role in how biologists "find" new species. The natural history collection plays a role in providing a "stage" for a new "actor" (in this case a possible new species) to be discovered!! 

    On multiple occasions I've described how I've descried new species from different parts of the world. I've got the new species I've described listed here and I'm up to around 31 of them by now.

    Natural history museum collections are a natural place to describe new species because in many instances, you ALREADY have the other species present as a reference species for comparison as well as much of the literature.
    So, whether this is just comparing the morphology (i.e., the external or internal appearance) or if you are taking DNA from tissues, museums with their many, MANY other specimens are often critical for such a study.

    Once a new species is described. It remains with the museum until one of three things happens: the specimen fades away OR the museum collection fades away OR human society ends.

    Either way.. vouchers for species are supposed to be kept "in perpetuity" and that's a LONG time...

    I have literally met the 4th generation of descendants of scientists visiting the museum who had specimens deposited in the museum based on work finished in 1846!!!

    3. Museum Collections: Where Scientists Gather
    In places where collections are present, they serve as a focal point for scientists, politicians, and even activists and other folks to meet. You have the collections that everybody needs in one place. Travel often takes place at the same time (e.g., during the summer or winter when school is out) and before you know it, you've got a workshop or collaboration happening! New projects! New species!

    During one of my last visits to Paris, a convergence of about half a dozen scientists from 4 countries led to a workshop on New Caledonian marine biodiversity!

    These efforts benefit everyone as folks get their "heads together" to pool data and resources in order to solve bigger problems and to examine big issues in conservation, biology and other related fields.

    4. Museums & their Collections are Research/Conservation Hubs
     Another aspect of research that ties directly to the collections: research and database hubs are often associated with museums. It makes sense that as researchers use additional tools, that these will be accordingly part of the modern museum infrastructure. Got the specimen with database information cataloged? Extracting tissue AND keeping track of that information are critical parts of the process.

    As part of this whole dynamic, many, MANY government and non-profit organizations hang their hats in and around natural history museums. You've got biodiversity databases and taxonomic information?  Then you've got researchers and others who need to research that information and manage it.

    5. Biodiversity Education
    The collections motivate and spur a lot of research and research-related activities. But one of the greatest non-research things about natural history collections is their ability to inspire and educate!

    Showing people "the real deal" is the often the BEST way to educate. Models and such are nice but when you are able to hold a 450 million year old fossil shell in your hands?  A REAL piece of history???

    Plus, you often have scientists and educators who know their way around specimens and are more than happy to share the details and explain in the best way possible??

    AND, many, many citizen scientist and natural history fans gather at museums. Many, MANY artists often sit and draw/illustrate specimens in the main display halls of many museums. Many citizen organizations meet at natural history museums..essentially inspired by the collections!!

    Collections motivate all of the activities above! But remember that they don't necessarily happen on their own! Sometimes you can take one from column A and one from column B!!

    How can you beat that??
    So.. SUPPORT your natural history museum and their COLLECTIONS. They play an important role in supporting biology and research.

    Even WITHOUT money for research activities, there's a lot of costs that go toward supplies.. labels, boxes, and most importantly trained personnel to help maintain the collections.

    Supporting science and biodiversity:  the discovery and understanding of new life on the planet is the mandate of every natural history museum I know of!  Natural History Collections are ESSENTIAL to this. If you can support collections- PLEASE do so!  Happy Taxonomy Day!!

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    I haven't done an art blog in quite awhile and this week I thought it would be cool to feature one of my favorite natural history illustrators! John Meszaros at Nocturnal Sea!   and here is John's Deviant Art Gallery! if you'd like to see more.  and his Facebook Page with many cool pictures! 

    You may already be familiar with some of Jon's work as he illustrated the recently described new species Xenoturbella monstrosa based on research at Scripps by Greg Rouse et al. 
    Here's the real deal for comparison. The illustration above shows the ecology of Xenoturbella as described by Rouse et al.. so however.. unusual the image may seem it is based in real science!

    Another striking image that I LOVE is this one from Jon featuring the hydrothermal vents of Antarctica, featured a few years ago here. But specifically.. the unusual multi-armed STARFISH that live there!

    They apparently fed on the weird fleshy barnacles that live there as well as possibly the "Hoff crabs"! 
    For comparison..
    Jon has always had great taste in subjects for his paintings! (and good colors to match) Here is the famous swimming sea cucumber, Enypniastes exima. Which you can also buy as a shirt! 

    and Yes....the swimming sea cucumber is REAL

    Another one of my favorites is Megalodicopia hians! the deep-sea predatory tunicate! Another lovely painting! And yes.. here's where you can get the shirt! 
    Jon draws inspiration from a wide range of habitats in nature! Fortunately they are all unusual!!

    Here's a GREAT one called "Inner Space 2" which shows a bunch of very small pond-water type animals and protists...

    The big "tree-like" things are actually rotifers in the genus Floscularia! He actually goes into a detailed description of everything in this picture on his Deviant Art page for this illustration.  All of the things in this painting are actually microbial organisms that you might find in a drop of water in a freshwater pond or lake! There are bryozoans and even ciliates (protists)! 

    Inner Space 2 by NocturnalSea on DeviantArt

    Another great piece of art shows none other than one of the weirdest, little animals known-the Loricifera! Here as part of this anoxic habitat inspired by a brine pool from the Mediterranean.

    Cabinet of Curiosities:  An Anoxic Metazoan by NocturnalSea on DeviantArt

    Here is a nice cross section of tropical invertebrates.. including not just the colorful and already surreal nudibranch Bornellia, but also one of my favorite sea urchins, the "shingle urchin"Colobocentrotus as I wrote about it here.  and here for the biophysics of their ability to hold on...

    John also does some pretty AWESOME paleontological reconstructions! 

    Here we have some art depicting the Sirius Passet laggerstatten from Greenland. A Cambrian deposit which is faunistically similar to the Chiangjiang and actually pre-dating the Burgess Shale fauna..

    Sirius Passet fauna by NocturnalSea on DeviantArt

    The following two are more of my favorites taken from the Cambrian faunas.

    LOBOPODS! Remember Hallucigenia and the other weird critters from the Burgess Shale? These were arthropod-worm like animals that were thought to be distant ancestors to velvet worms..

    Lobopods by NocturnalSea on DeviantArt
    And in the same vein, here are anomalocarids.. species of Cambrian arthropods related to/inspired by the famous Burgess Shale Anomalocaris

    Anomalocaris group by NocturnalSea on DeviantArt

    And as all artists are want to's a more fanciful creation inspired by real Paleozoic animals. Included here just for the sheer fantastic artistry of it!

    False Ammonite by NocturnalSea on DeviantArt

    Here he's clearly taken a VERY echinoderm-centric take on the Great Race. We have some echinoderm larvae in there as well as a brittle star and some five-part symmetry that any worshipper of the great Cthulhu would approve of (if they were not seeking to bring about the end of humanity that is! )

    Haeckel Yithian by NocturnalSea on DeviantArt

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    This week I thought it would be fun to revisit the wonderful world of stalked crinoids!  I've previously looked at photo galleries of deep-sea living stalked crinoids hereand a few from the Hawaiian Okeanos expedition.

    Here's a hyocrinid "pinwheel" crinoid form the Okeanos dive to Indonesia! (INDEX-SATAL 2010)

    For those who might not be familiar with stalked crinoids, they are the ancient ancestors of modern day feather stars (aka comatulid crinoids).
    feather star  Oxycomanthus bennetti

    Stalked crinoids are fundamentally composed of three main regions: the calyx (or cup), arms and stalk which is very nicely illustrated by this diagram from the Field Museum in Chicago!

    Stalked crinoids feed on food particles in the water column using their arms which they move down to the mouth located at the top of the calyx (or cup). The stalked and unstalked forms have an unusual relationship which you can read about in an earlier post here.
    Sea Lily Fossil
    The high point of stalked crinoid diversity was in the Paleozoic, some 250 to 540 million years ago in the time before dinosaurs..there  existed a HUGE diversity of stalked crinoids.. and even DURING the time of the dinosaurs in the Mesozoic there were still quite a few of them (as I'll share below)..

    Let's start off with this gorgeous one calledAcanthocrinus rex! from the lower Devonian of Germany. This image was reported by crinoid scientist Hans Hess as "certainly one of the most beautiful crinoids ever found.." Sadly, this specimen was lost in World War II.
    This image from:
    The images below are a nice set of Paleozoic crinoids by James St. John on Flickr..

    Here is the Paleozoic Taxocrinus colletti from the Edwardsville Formation, Lower Mississippian; Crawfordsville area, Montgomery County, Indiana, USA.
    Taxocrinus colletti fossil crinoid (Edwardsville Formation, Lower Mississippian; Crawfordsville area, Montgomery County, Indiana, USA)
    A striking one called Platycrinites saffordi from the Edwardsville Formation, Lower Mississippian; Crawfordsville area, Montgomery County, Indiana, USA.
    Platycrinites saffordi fossil crinoid (Edwardsville Formation, Lower Mississippian; Crawfordsville area, Montgomery County, Indiana, USA)

    One with some strikingly different arm branching patterns: Onychocrinus exculptus from the Edwardsville Formation, Lower Mississippian; Crawfordsville area, Montgomery County, Indiana, USA.
    Onychocrinus exculptus fossil crinoid (Edwardsville Formation, Lower Mississippian; Crawfordsville area, Montgomery County, Indiana, USA)

    Here is: Onychocrinus ulrichi a fossil crinoid from the Edwardsville Formation, Lower Mississippian; Crawfordsville area, Montgomery County, Indiana, USA.
    Onychocrinus ulrichi fossil crinoid (Edwardsville Formation, Lower Mississippian; Crawfordsville area, Montgomery County, Indiana, USA)
    David Clark on Twitter brings us this interesting one with large spines emerging from the calyx! The aptly named Acanthocrinus! (from the Devonian of New York)
    This next series is from Elrina753 (thanks for the awesome images!) from the Houston Museum of Natural Science. These look like the Mississippian, Platycrinites
    Another gorgeous one from the Houston Museum of Natural Science: Onychocrinus exsculptus
    Onychocrinus exsculptus

    And this third one from Houston which I don't have a name for...

    An interesting Paleozoic one called Eretmocrinus (no other info, so unsure if ID is correct) but the arms have very unusual morphology. Notice how they become paddle like towards the tips! 

    And from the displays/collections in Washington DC at the NMNH.. the massive Jurassic Seirocrinus which was actually thought to be pelagic and might have attached to floating logs! More on these two unusual swimming/floating crinoids here.

    The bizarre Uintacrinus which some thought might have actually dragged its arms over the bottom as as it floated by...

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