Wednesday, January 14, 2015

AMPHIPODS! Tiny Crustaceans that show AMAZING colors!

Image by Arthur Anker
AMPHIPODS! What are they? Small, very diverse crustaceans that occur all over the world in marine, freshwater and even terrestrial habitats. They are distinctive in that their bodies are laterally compressed, in other words, their bodies are "taller" than they are wide.

There's a bewildering diversity of them with over 9500 species known.
Most of them are pretty tiny (about 1.0 to 20 millimeters) but some giants approach 34 centimeters (13 inches!).. such as these supergiant amphipods which live in the abyss of the deep-sea at 7,012 meters!

There's a MASSIVE amount of diversity within the group. Some are transparent, while others are colorful. Sometimes they occur in huge densities and are often thought of as the "bugs" of the sea. They often act as detritivores/scavengers as well as predators..

I thought today might be a good idea to share some of the more unusual body forms, courtesy of the highly talented photo naturalists on Flickr. Enjoy!

Epimeria loricata by Olga Zimina

Apparently 2 different color morphs of Paramphithoe hystrix by Olga Zimina
A "Jewel beetle" amphipod by Arthur Anker

A stunning podocerid? from Arthur Anker
A stunning hyperiid...


Some interesting "reef aquarium" species by Waldo Nell
the same under green filters/light!

Some Antarctic amphipod goodness (Echiniphimedia hodgsoni ,family Iphimediidae-ID by Marie Verhaye!) from US Antarctic Research Program at the NMNH

and a delightful species from the White sea.. by Alexander Semenov

There's this stunning beauty, ..also by A. Semenov

Wednesday, January 7, 2015

Pegaster stichos A Cretaceous California starfish example of Paleo History!!

This week, I am in California on my way to Japan! I am visiting the world-renowned Invertebrate Zoology & Geology department at the California Academy of Sciences in San Francisco! 

I used to work here when I was a grad student at San Francisco State University in the 90s and as such I have a long-standing relationship with colleagues at the museum.
While going through the collections, I encountered a specimen of this awesome classic fossil, the Cretaceous Pegaster stichos, a starfish belonging to the family Stichasteridae described by my former PhD advisor, Dan Blake and Dallas Peterson in 1993 in the Journal of Paleontology. Their specimen is below...

                                
The CAS specimen (CASG 68139)  is also from the Cretaceous of California... (my thanks to Dr. Peter Roopnarine @peterroopnarine and Collection Manager Dr. Jean deMouthe for their help!)

If some of you are "old timer" San Franciscans.. you may even recognize that this fossil was originally on display in the old CAS Life Through Time Exhibit!!
                                
These specimens (and others like them) are powerful pieces of evidence for how the distributional ranges of marine animals has changed over time. 

but first.. just a little introduction so we're all on the same page...

The starfish in question belongs to the Stichasteridae, which is a group of forcipulate starfishes. I wrote about the curious pattern of biogeographically arranged lineages in the family tree of these animals awhile back...

Note the purple arrow below. The Stichasterids are down at the base of the tree. Given that the record of this whole group goes back to the Triassic, the fact that they are still around is pretty cool.
BUT most members of the Stichasteridae in MODERN oceans live mostly in the Southern Hemisphere (shown here by Stichaster australis), usually seen in Australia, New Zealand and/or the cold-temperate part of South America

As I've blogged before, shallow water members of this family are often times convergent with sea stars in a different family, the Asteriidae from intertidal habitats in the Northern Hemisphere..

But most members of the Stichasteridae are absent from the Northern Hemisphere EXCEPT in the deep-sea, such as this Neomorphaster we saw in a 2013 Okeanos Expedition, where they can be surprisingly abundant..

The only other EXCEPTION to this occurrence in the northern hemisphere is from FOSSILS!! 

Behold this awesome specimen of the Cretaceous stichasterid, Pegaster stichos!! 
                                 
So, this shows that at ONE TIME, this group of sea stars lived in the Northern Hemisphere and in the Pacific, perhaps even more widely than was previously known. Note also that in this time period, a good chunk of the west coast of North America was underwater...as well as a good parts of Texas and the south..
From NPR: http://media.npr.org/assets/img/2012/10/09/late-cretaceous_wide-e3fc2fd33eac021deb4b6ac5b4d87cb80d50f9f2.jpg?s=6
For most of us, we think of the Cretaceous as the time of the dinosaurs and other big marine reptiles!
from the NPS National fossil DAY page! 
But MANY a starfish and sea urchin was around during those days...

and sea urchins of course!

What happened to them??  Extinction apparently. Or maybe they just moved into more friendly waters?   Why?? Any number of factors including sea level and/or climate change.


Where do modern faunas come from? They were here and there.. and sometimes we can see them back then....

Wednesday, December 31, 2014

New species I have known.... 2014 UPDATE!!! (originally published Sept. 7, 2011)

In 2009 (Sometimes even I can't believe how long I've been writing this blog!), I wrote a post that illustrated the results of my published papers. Most people may or may not realize that I'm an active scientist who works on the evolution and diversity of asteroids (aka starfish or sea stars). And even when I tell them.. most folks don't really SEE what it is that I've done.

Part of my research involves TAXONOMY. The description and classification of different species. Biologists who are specialists in taxonomy are present for all organismal groups-from folks who work on protists and fungi to insects, parasitic worms, dinosaurs and the list goes on.

Sadly, the ranks of scientists who practice any kind of taxonomy is shrinking. Why? There are a multitude of reasons that have been offered...
-the need to work on research that secures larger funding sources
-the lack of universities that continue to teach organismal coursework
-the absence of perceived importance of taxonomic research
-changes in the basic pace and emphases of evolutionary research..

All of which go hand-in-hand with the so-called Great Biodiversity Crisis. Essentially the combination of a perceived "happening right now" extinction coinciding with a steady decline of workers who can describe and list how many species exist on Earth. A nice write up by my colleage Craig McClain from Deep-Sea News in Wired on this subject can be found here.
In my case-I am one of the few remaining, world specialists who work on starfish. The number of people who ID sea stars at my level can literally be counted on one hand.

In the time since I've started my professional career, I've described (as of Sept. 2011) over 2 dozen new species (plus some new genera), I have about 3 dozen publications and I oversee the World Asteroidea Database.

Most of these are present in the Goniasteridae-one of the most diverse groups in the Asteroidea and thankfully, a group that I know a thing or two about.....

What I hope to accomplish here is to give some substance to my accomplishments and a tangible sense (limited by the fact that they are pictures of course!) of what diversity remains to be found. And what sorts of animals have been described only in the last few years! 

And many more remain to be discovered..

Some various miscellany that you may notice.. So some answers to anticipated questions..

Yes. I do occasionally name species to honor people who have supported or contributed to echinoderm research.

No. I wouldn't name a species after myself. That's considered poor form within the profession...

Here is a "yearbook" of the many new species I've described...Its still incomplete and I will be constantly updating..

2014 (up to 25 species as of June!)
UPDATE: June 2014 Three new species of Hippasteria in the Zoological Journal of the Linnaean Society. 

Blog is here. 

Hippasteria muscipula from the tropical Pacific
 Hippasteria tiburoni from Pioneer Seamount
 Hippasteria mcknighti from New Zealand

May 2014  Two new genera and species of Poraniidae in the journal Zootaxa  The blog post is here. 

Here is Clavaporania fitchorum from about 1600 m south of Macquarie Island
 And from Davidson Seamount off central California- Bathyporania ascendens!

2011
Two Antarctic species! Both of these were named in a recent paper 2011 issue of Zoosystema 2759: 1-48

Chitonaster trangae 
named for Trang Nguyen at Oregon State University! A dedicated worker that previously worked for the US Antarctic Research Program!
And a new genus and speciesEratosaster jennaenamed for Jen Hammock the administrator of the USARP program who now works for the Encyclopedia of Life..

2010
Sthenaster emmae which I described in 2010 in the Zoological Journal of the Linnean Society
This deep-sea beast was described from the Tropical Atlantic. Named for Dr. Emma Bullock, a meteoritical geologist in the NMNH Mineralogy Dept.

One of the more rarely-encountered species I've described-the very spiny Evoplosoma claguei
A North Pacific deep-sea coral-predator that is named for Dr. Dave Clague, a geologist working for the Monterey Bay Aquarium Research Institute! This species was featured in an MBARI video on coral-devouring sea stars...

2007
From my 2008 paper....a new genus and species of pentagonasterine goniasterid from New Caledonia.... Akelbaster novacaledoniae !


From the same paper, a new genus and species of goniasterid from the Ryukyu Islands in Japan:
Ryukuaster onnae !
From that same paper of mine in 2007 is a new species from New Caledonia of the genus Eknomiaster-Eknomiaster beccae. Named for my colleague Becca Price at the University of Washington.
Look! Its got some fun pedicellariae surprises on the underside!

2006
Xyloplax janetae! From Invertebrate Biology 125(2): 136–153. 



Circeaster arandae Fr. deep-sea in the Indian Ocean from my 2006 paper in the French journal Zoosystema (28)4:917-954
Circeaster loisetteae from the Solomon Islands..

Circeaster sandrae Fr. the central-South Pacific..
This species occurs in the deep-seas around New Caledonia and is named after my colleague Dr. Sandra Brooke!

There were others from this paper ....

2005
From my 2005 paper reviewing two genera of goniasterid starfish from the tropical Pacific: Glyphodiscus magnificus and...Glyphodiscus pentagonalis 


and this wonderful beast, Iconaster vanuatuensis

2003
The first new genus and species I ever described!! From a paper I wrote in 2003: a new genus and species of Oreasteridae from the subreef zone:
 
Astrosarkus idipii
 from Palau and the southern Indian Ocean

Wednesday, December 17, 2014

A simple guide to Tropical "cushion stars"! Halityle vs. Culcita spp.!!

From Wikipedia.. they are GREAT! Go give them some money! 
Today.. a short instructional on tropical "cushion stars" which is a common name I HATE because it just describes so many different types of sea star species..  BUT if any one starfish species COULD be the "rightful" bearer of THIS common name, its the one called Culcita.

Why?  Because its name is LITERALLY translated as "pillow or cushion" but for comparison, there's another similar looking beast called Halityle regularis. I see the two mistaken for one another all the time.. so here's the two genera for comparison...

This one is Halityle regularis. One species known, widely occurring from the Indian Ocean (Madagascar) to southern Japan (the Ryukyu Islands) and Australia and New Caledonia.

Interestingly, there are two colors I've seen on Flickr... This red one from Indonesia.

versus this more purple one... Not sure if this is simply an artefact from the lighting of the photography... Here's another one that seems more deeply purple..


Haltyle has a very strongly defined net-like diamond pattern on the top surface and with the distinct colored region on the oral sufrace...


Here is Culcita
In terms of appearance, Culctia is a bit chubbier, and more compact, but the patterns on the surfaces are more cloud-like and are not as distinct.


Especially on the oral surface, which depending on species is a bit rougher, almost spiny



Culcita  has THREE species, C. schmideliana from the Indian Ocean and C. coriacea, which is known primarily from the Oman region and finally the most widely occurring species C. novaeguineae which is found all over the Indo-Pacific. But mostly the Pacific.

We don't know that much about Culctia, but we know a little. The most widely occuring species, C. novaeguineae also eats coral but nowhere near the volume or severity that the dreaded crown-of-thorns starfish does.. Culctia's role is just as important though, in that it aids in community structure.. It feeds on certain kinds of coral and this influences how coral colonies grow...

As I've written about before, when they are young, they have a more flattened, pentagonal shape.. and as they grow, they "inflate"...
Here's a living one for comparison..

Here is the Indian ocean species, Culctia schmideliana  which is distinguished by the very large, dark granules/nodules on the body surface..

As with all the species, there appears to be some variation in color and degree of granular presence...



Culcita coriacea from the Gulf of Oman...These seem to have these larger dark regions and without the large granules but a more overall even surface..


And finally, the most widespread species in the Pacific 
Culcita novaeguineae
C. novaeguineae is HIGHLY variable.. it comes in MANY colors throughout its very wide range, in the Pacific, including Hawaii, Japan, the Philippines, Singapore, New Caledonia, and elswhere....which suggests it is possibly a bunch of cryptic species...

Surface on these is largely covered by granules or tiny spinelets....None of which seem to get very large.

Some, such as this Japanese individual have tiny spinelets...

Based on Flickr photographer "Nemo's great uncle", the Japanese name "マンジュウヒトデ饅頭" roughly translates into "steamed bun starfish".

Mmmm...steamed bun... Awesome...

Colors in this species are HIGHLY variable.. what is the significance? Different species? Different food? Simple random variation??



More RED spines!! (Thailand)

Some interesting color contrast between the top and oral (bottom) surfaces..
in spite of their massive appearance, they are surprisngly flexible..

Here's one arched pretty strongly and doin' the cushion star equivalent of TEH SEX!! Gametes GO!!!

And on that note! Happy holidays from the Echinoblog!! I will be more irregular with posts over the next two weeks...

Tuesday, December 9, 2014

WHAT is going ON HERE? A galloping herd of urchin! CRAZY Maretia planulata heart urchin aggregation!


Every once in awhile, I think that I might finally have run out of stuff to share with people and THEN something magic happens. Some fantastic new video or pic pops up and WOO! The diversity of echinoderms and the infinite resourcefulness of the Internet pop out of nowhere with some magic NEW biology to share!!

Case in point is this video, which was shot by "Dive Yos" showing various cool inverts spotted during a dive in Bali. The video was posted 2 months ago...

It starts with a few typical things, a sea anemone, sea horses, etc. a lot of typical fare...but then we see one, two, four heart urchins, six... and then at 0:27 into the video?  BOOOM!!! You got this HUGE heart urchin stampede!!!

Best as I can tell, these are the heart urchin, Maretia planulata, described by Lamarck in 1816. This species of urchin lives throughout the tropical Indo-Pacific, from Tanazania to the Marshall islands...

They live in relatively shallow water on the surface of sandy bottoms.

Here's what one individually looks like.

Heart urchins are "irregular urchins" which are closely related to sand dollars. I wrote up a post on a related animal called Echinocardium, which you can find here




But WOW! What is going on with this HUGE aggregation??

As I've written before, other "regular" urchins sometimes form "urchin barrens" when the ecological balance of a particular region is out of whack and you have TOO many of them eating EVERYTHING in sight...

I have no idea if this huge "herd" of urchins is "natural" or not..

But the thing is, Maretia is a heart urchin (aka a spatangoid). They are sediment feeders, so they don't really eat kelp.  I suppose the absence of some predator might be the cause. And the huge numbers could STILL deplete food in a given region, but this high abundance seems to be a regular thing.

There are other websites which have also observed that they occur in high numbers like this... Such as this one displaying this aggregation.
Photo by Geoffrey Bertrand, on his website
The most I could find on the literature about this 'herd' of urchins was from 1986. Thomas Suchanek and Patrick Colin in the Bulletin of Marine Science , vol. 38(1): 25-34, noted that this species was abundant reaching 100-200 per square meter!!!  and that they processed "massive amounts of sediment"

I would love to know more about whatever is going on here. Or maybe this will be the beginning of someone's Phd thesis? Don't know. But the thought of 100s (thousands?) of these things galloping along the bottom of the Indo-Pacific sandy bottoms is just... farking AMAZING!

Announcement for the 15th International Echinoderm Conference in Mexico!!

Coming up Next year is the 15th International Echinoderm Conference to be held in Playa del Carmen Mexico!

The official IEC website for this conference is here:  http://www.icmyl.unam.mx/15iec/

Twitter: https://twitter.com/@15iec
Facebook: https://www.facebook.com/15IEC

The conference theme will be: “Echinoderms: from molecules to continents”.

The IEC is held about every 3 years, and rotate around the world. The last one (the 14th IEC) was held in Brussels, Belgium.  A full overview of Echinoderm Meetings and Conference Proceedings can be found here. 


Monday, December 1, 2014

The Strange Deep-Sea Ophiuroids of Paris! Featuring Dr. Tim O'Hara!


Bonjour once again!! So, my trip to Paris has all but ended and I'll be returning to the United States in a few days. The trip has been a challenging one. The laptop crashed and was out of the loop for two weeks and left me without a computer for data collection and etc..

So, much of my trip has been "old school".. working with paper and notes labelling jars with species names as best as I can...
Although data collection has not been as efficient as I like, I have done the Paris Museum (my host) some good by identifying a massive number of specimens in the collection...
I not only got through many of these older specimens but several of the newer ones as well...
All said and done, I've identified around 900 specimen lots for the museum. Given that Paris probably contains the largest collections of asteroids in the world, that is no small feat!!

But one of the GREAT things about this trip is that my visit, inadvertently overlapped with a trip being undertaken by one of my colleagues. Dr. Tim O'Hara at the Museum Victoria in Melbourne, Australia!! One of the world experts on ophiuroid systematics and ecology! 

I have written about Tim's work before:
  1. This new species of the Australian starfish Tosia, which was described by one of his students.
  2. This fantastic biogeographic pattern in brittle stars which he published several years ago! 
  3. Tim was also the one who identified and, in part, documented "Brittle Star city"
Tim and I are friends from waaaay back. We worked together in the museum in 1999 before either of had our PhDs and its strange to think of that being almost 15 years ago...  

I had a great chance to learn about weird brittle stars from Tim and so I did!!

Learning about weird, deep-sea brittle stars with Dr. Tim O'Hara from Museum Victoria! 
Tim was working with deep-sea biologists at the Paris Museum who are interested in New Caledonia.  (I am one of them).  Some may remember that this time last year, a huge new marine reserve was created in the New Caledonia region. 

Thus, Dr. O'Hara's ecological and taxonomic expertise was brought to bear... not only to identify brittle stars...
but ALSO to share his new cutting edge research with the greater scientific community! A recent paper by Dr. O'Hara has used cutting edge "Next Gen" technology, using over 425 genes to reconstruct the "family history" of the Brittle Stars.  

Its noteworthy not only for the fact that he used an exhaustive amount of genetic data, but he was able to sample and identify ALL the brittle stars necessary for the study! Not an easy feat when you can count the total number of brittle star  taxonomy experts in the world on one hand! 

Here is Tim giving the presentation to a full room of French scientists and colleagues (myself included) in the Paris Museum...

The important part of ALL of Tim's work is being able to identify all of these strange, deep-sea brittle stars from distant parts of the world...  and he was happy to share several of these with me...

1. Amphiophiura insolita!! Don't know much about it, but its got a spectacular rose-like disk pattern...
This specimen of Amphiophiura bakeri was huge! Almost 2 cm across! It looked like an egg had grown five arms! 
2. These two different species of the deep-sea Ophiomusium make it easy to see why brittle stars are so difficult to work with and identify.
                           
                            

3. The tiny male living on the large female Ophiosphaera insignis!!  Notice all the white arrows.. Those point out the arms of the tiny, smaller male.  He lives on the female.

Its unusual for there to be two distinct sexes in echinoderms. In this case, it is thought that this might be a pattern similar to that observed in anglerfish. The male is essentially a parasite on the female. 


4. One of the strangest of deep-sea ophiuroids is almost never seen by most people. This is the ophiuroid Ophiomyces, which has this bizarre sac-like disk membrane..  



Its certainly freaky enough that its hard to believe that the picture really captures what the animal looks like, so here's an actual specimen. Its only a few cm across..
Here's one museum specimen, which as treated with metal for scanning electron microscopy...Its still kind of a surreal looking animal....
  

5. A related brittle star is this genus, Ophiotholia, which differs in having funny little hooks on its spines... but has a more distinctly conical disk and specimens are always found with arms locked upwards.

Again, a fairly small animal, only about 1-2 cm across. The drawn image on the left is from a plate of this species from the HMS Challenger vs. the right one which is an actual specimen...

       
And amazingly, thanks to all of his molecular work, Tim now also has a very good idea where these strange critters go in the big "tree" of ophiuroid evolution!! 

Ophiuroids are just a whole bunch of crazy sh*t that just makes my mind POP!!