Thursday, August 10, 2017

Okeanos Explorer Communities & Deep-Sea Discoveries!

I'm BACK! After a month at sea with 2.5 weeks worth of dives I've safely returned to "home base" in Washington DC! I was out in the central Pacific with NOAA's R/V Okeanos Explorer on their Laulima O Ka Moana expedition, exploring the deep-sea of the Marine National Monument in the Central Pacific! 

1. Forest of the Weird: Land of the Glass Sponges!
This was probably the most amazing thing I have seen in awhile! (at least since that Basket Star community in the Marianas a few years ago!)

So, the key thing about nearly ALL Of these sponges? Many of them are what's called GLASS SPONGES aka members of the Hexactinellida. That means they have bodies which are made out of silicon oxide!

These often have bizarre and weird shapes. I have done a post about these before here in 2015.

Here's a highlight video of the discovery-basically water currents ran at an ideal rate at the top of this geologic feature making it IDEAL for what seems to be a huge abundance, if moderate diversity of glass sponge species!

Note also how all of them are turned into the current!! We were in this "forest of the weird" for the remainder of the dive (over an hour) so there was quite a lot of it..
Here's few more that show off the crazy architecture.. These varied in height from one to four feet in height..

2. The Carnivorous Sponge Field
This area was kind of the opposite to the one above. Rather than big and obvious, it was quite dense and discontinuous, being present on one big boulder to another...

But what was amazing was that this was composed of a different type of sponge in the family Cladorhizidiae. (possibly in the genus Asbestopluma..) Cladorhizids are not glass sponges and have physical properties more like what's seen in many other sponges. EXCEPT...

...that they are CARNIVOROUS!!!

Wait.. WHAT? Yup. MOST sponges are filter feeders. But in this group, they use glue or spines to capture prey, which are then digested by the animal in question. We've seen different types of these carnivorous sponges before, including some possible new species..  These sponges kind of look like a feather.. a central stalk with fine hairs or spines coming off the sides

Similar to this species in the NOAA benthic inverts guide...

Here..they were present in HUGE densities.. alongside some frond-like bryozoans! and some stoloniferous zoanthids (a sea anemone like cnidarian)  These actually seemed to be pretty thin at first but got bigger, longer and thicker as we encountered them!

Yes.. I suppose I'm overhyping them..but that's basically a "killing field" of carnivorous sponges!  with these projecting into the
Interestingly, this shot above looks like there might be a snail on one of those even more going on!

3. This Amazing Farreid Sponge/Acanthogorgia Wall! 
Shallow-water dives can be VERY productive but because of the nature of Okeanos Explorer we tend not to do many of them relative to the really deep dives (>1000 m).

The one we did at Johnston Atoll did NOT disappoint!

This large block and several like it had this AMAZING side flanked on one side by sponges in the Farreidae, but then on another side covered by octocorals in the genus Acanthogorgia!

The coral side (Acanthogorgia) was relatively high current...
versus the "sponge side" which was relatively low current...

and many critters were to be found amongst the corals (such as this... sea slug)

3. Astrophiura! the "sea star ophiuroid" Probably one of the MOST memorable observations for me OUTSIDE of the starfishes was this weird little brittle star!

One of the videographers, Bob, saw it adjacent to the base of one of the sponges. And there it was plain as day!

These animals are TINY. Maybe dime sized. So, the D2 camera's caught a really RARELY ENCOUNTERED and SMALL species.. (about 2000 m depth)
This genus of brittle star was described in the 19th Century by Walter Percy Sladen, the author of the HMS Challenger sea star monograph. He hypothesized that it was some kind of "missing link" between brittle stars and sea stars... (since been disproven)

Here is some imagery of as illustrated by H. Matsumoto.. It has rather famously been shown in echinoderm books as an example of a bizarre form.  Its shape is very similar to those caymanostellids and is thought to be an adaptation to lying flush on the substrate..

Astrophiura kawamnrai n. sp.
Image from page 210 of "Aus den tiefen des weltmeeres" (1903)
Image from page 662 of "Annotationes zoologicae japonenses / Nihon dōbutsugaku ihō" (1897)

4. Pumpkin Sized Echinothuriids Sea urchins! 
This dive started out pretty uneventfully up slope along a cone, resulting in the discovery of a pretty amazing colony of plexaurid corals

As I've mentioned with some of the OTHER high density communities- not only were there corals present but LOTS of other animals living among them.. 

One of the most remarkable? These HUGE echinothuriid urchins!!  For those who might not be familiar.. these are aka "pancake" or "tam o shanter" urchins. You can see more about them here (with links therein). 

Basically, these are soft-bodied sea urchins which often have poisonous spines and little walking legs.

But the ones we saw on this peak? just ENORMOUS.

The lasers are 10cm across,(about 4 inches), okay this one is only about 8 inches across
but we panned across to another ledge and found a few more...
This darker brown one ended up being about 2 laser about 8 inches across! that's basically the size of a small pumpkin! do they get bigger?

Wikipedia lists the "largest" species at 14 inches (36 cm) but did not elaborate on species..(will need to check). But if that's the upper limit, then 8 inches is definitely monstrous!

5. A deep-sea... NUDIBRANCH??
This one was quite a surprise, because I had largely thought that sea slugs were limited to relatively shallow depths, much less PROPER nudibranchs which are overwhelmingly found in nearshore settings.

This looked pretty bigh on camera and was about 5 inches long? when we collected it..

Amazingly, there is one genus of proper nudibranch in not only the Antarctic but in the deep-sea: Bathydoris!  I'm not sure quite yet what they eat but will find out!

How will the species we collected compare??? Stay tuned! (and thanks to Vanessa Knutson for her help with the ID!)

That's a quick recap of some of the non-sea star events..but I'll post more as opportunity permits!  THANK YOU to the crew of the Okeanos Explorer, NOAA and my science team colleagues for inviting my participation!

Tuesday, June 27, 2017

BIG NEWS!!! Echinoblog Will be ON Okeanos Explorer!!

Some EXCITING news! I have signed on to join NOAA's research vessel Okeanos Explorer as the Biology co-Lead for their July Expedition Broad casting from (approximately) July 13 to August 1!
This expedition will research the coral habitats around the Johnston Atoll unit of the Pacific Remote Islands Marine National Monument (PRIMNM) spending about 2.5 weeks performing ROV operations, mapping and exploring the biology and geology of the Johnston Atoll region! 

Those of you who follow me on Twitter know that I have live-tweeted the Okeanos Explorer dives for a couple of years (here)  in addition to providing identifications for the Facebook Screengrab Group as well as blogging about highlights observed during the dives (here). 

I have been a long-time "shoreside scientist" contributor providing identifications of starfish/sea star identifications as well as whatever knowledge about deep-sea echinoderms (or other animals) I can contribute.

Will you still be live-tweeting your dive? 
Unfortunately, I won't be providing quite the same level of social media coverage since I will actually be working ON The ship, but when I can, you'll definitely continue to see me on Twitter. Its going to be busy onboard the Okeanos Explorer-but I will try to tweet as opportunity permits.

But I WILL be tweeting about as many aspects of the experience as I have an opportunity to!

Will you be Answering Questions via Social Media???
Yes! If you leave questions in the comments of my blog or on Twitter/FB (@echinoblog) with #askEchino (along with #Okeanos) I will try to answer your question when I am aboard ship during the live stream.  So, I probably won't immediately answer questions until I start the live stream. Questions answered will be at my discretion. 

I will share more on my Twitter feed as information becomes available. 

Wednesday, May 31, 2017

Five Highlights from my NEW paper about the genus Ferdina and its relatives!

GREETINGS! Last week, a new paper I've literally been working on since I finished my PhD has FINALLY been completed! Its easily my largest monograph at the moment and includes a whopping 14 new species, 3 new genera and a new subfamily!

For those who are interested, it was in the latest issue of Zootaxa, published online here (I don't believe the print version is out yet). 

The paper focuses on a group of tropical shallow/deep goniasterid sea stars which include reef setting genera such as Neoferdina but also seldom studied genera such as Ferdina and their relatives. I actually ended up describing 3 additional new genera and MANY new species!

Its always nice when the work is done and the specimens can go back to their home institutions.. many of these specimens were from the echinoderm collections at the Museum national d'Historie naturelle! 

Although the paper is "old school" and was done without molecules, to me it still represents a good example of taxonomy in the 21st Century?  I've written about how taxonomy has been done with new technology and other aspects here..

The whole thing is a lot to unpack.. and so here's some take away lessons that I thought I would share from writing it!

1. Citizen Science & Social Media Made a Significant Contribution! 
I've talked about this before.. the world is flooded with divers, photographers and interested people with cell phones all over the world! 

Thanks to a combination of museum collections and divers I was able to identify and describe several new species and even add color variation to poorly known species in the group I published on! Many times these get misidentified as people try to "shoehorn" them into known species in field guides. 

This new species for example, Neoferdina oni from the Philippines! I actually identified this species based on material collected by the California Academy of Sciences from one of their recent expeditions (such as this one)

The photographer of this specimen, Martha Kiser was incredibly helpful in allowing me to see her photos of this new species. You can see more of her work on Flickr here:
Neoferdina glyptodisca sea star ind10 3429
I will likely do a separate post on the etymology of these new species a bit later, but the species epithet of this one "oni" represents a horned demon from Japan which alludes to the two spines on each plate along the side!

Images such as this one gave me more insight into how the colors vary in already established species! and provide leads to possible NEW species...
Sea Star, Neoferdina insolita
Cuming's Sea Star (Neoferdina cumingi)

2. The Mesophotic Zone: New studies and new Species! 
There's a depth region in the ocean that falls just below "coral reef" (~30m) depth but just above the "deep sea" (above 200m).. that's roughly between 100 and 500 feet. More about this area here. and this entire website devoted to this area! 

This area is also known as the "Twilight Zone" aka the "sub Reef area" and contains a fauna that is related and similar but distinctly different from those seen at the surface. 

The California Academy of Sciences's research division as well as their Steinhart Aquarium have both been studying this area in the Philippines. In 2015, they collected this lovely beast, (and here was a news account showing it off) which I had also been observing in the Paris collections from areas throughout the Indo-Pacific!

I initially identified it as a familiar genus, Neoferdina, but eventually realized it was actually a separate and undescribed genus which I named Bathyferdina! 
I've actually been describing Mesophotic Zone starfish for quite a long time. Here was Astrosarkus idipi from many years ago aka the "Great Pumpkin Starfish" and there were several more as well...

One important take away message: Describing new species is PART of understanding the biology of a NEW ecosystem. This was the same thing that happened with understanding all of those predatory coral starfish.. new species led to understanding each "character" of a new ecosystem!

3. Museums & Travel: Where the New Species Roam 
Here's a neat new species from the western Indian Ocean-Madagascar and the east coast of South Africa.. Ferdina mena! Identified by the two distinctive bald patches present in each interradius (i.e. the "armpit") of the starfish.

Thanks to the stunning photos of "Optical Allusion" I was even able to find living images of this species in South Africa!
Starfish, Ferdina sadhensis
I have a strangely long history with this species.. I identified one of these (mistakenly) for the field guide Coral Reef Animals of the Indo-Pacific by Terry Gosliner, Gary Williams, and Dave Behrens- as Ferdina sadhensis which was known only from Oman.

During one of my recent visits to Paris and the Museum national d'HIstorie naturelle in Paris, I discovered that this wasn't just an odd specimen with the twin bald, red spots in each was present on ALL of the specimens collected from a collection made from Madagascar!!
Starfish, Ferdina sadhensis
Following this, I was visiting the Iziko Museum in South Africa in 2015 and discovered the SAME species from the east coast of South Africa! Citizen scientists in South Africa also showed me MANY photos of starfishes which confirmed the specimens.

and to return to the citizen science angle.. images on Flickr further showed this species in Mozambique as well as further color and pattern variation of this species from South Africa thanks to photographer Derek Keats and others!
Sea star at Aliwal Shoal, KwaZulu-Natal, South Africa
In both cases, these specimens had been collected and sitting in these museums awaiting discover for YEARS. In Paris-2007 and 2010 and from the Iziko Museum collections-in 1986!!!

So, somewhere in there, this seems to be consistent with the "21 years" which malacologist Dr. Philippe Bouchet has published as the average time it takes for a specimen to get from collection to publication! 

4. Conservation: Aquarium shops & Misidentified starfish
This was an interesting lesson.

For one of the new species I had discovered, Paraferdina plakos, I only had one or two individuals on which to base my new species description. Were they the same? Was it variation? How do different individuals differ from one another? Are the defining characters the same across the species range?

SO, I took advantage of some aspects of the internet which I usually list as pet peeves...

1. Misidentified species made by people who don't want/need to figure out the correct species
2. Pictures of species collected by Internet aquarium and pet shops

I was actually able to make OVER TWENTY OBSERVATIONS of this species misidentified as the common "peppermint star" Fromia monilis!!
This led to ANECDOTAL information about its color and how individuals varied in shape. One or two sites actually were pretty up front about declaring how their specimens had been collected from Sri Lanka, suggesting a further occurrence point for this species.

What does this tell us? Not ONLY are A LOT of new species yet to be discovered but we are ALREADY seeing them sold in the pet trade.. and with no correct identifications by scientists to recognize them, are they endangered? For a species that has just been described we know NOTHING bout its reproductive biology, populations, can they handle the strain of being "fished" for this trade???

5. Mysterious Crystalline Nodules! MicroLenses? or just developing granules? 
On several of the species of starfish I've worked on, close examination of the surface revealed that there were HUNDREDS of these glassy crystalline nodules embedded on the surface of the skeleton!

In this  newly discovered genus and species from New Caledonia, Kanakaster solidus shows these crystalline bodies as a sort of pebbling all over the body surface, which is pretty suggestive of the microlens idea.. but I suppose they could also be incipient or underdeveloped granules which cover the body surface as almost a kind of thick tissue.
from Kankaster solidus, holotype

Whereas, in this species, Kanakaster discus, the crystalline structures are actually arranged in stellate formations rather than simply as granulated pebbling. Much more suggestive of a "lens" type function I would think.. but hard to say without more data.

from Kanakaster discus, holotype

If these ARE lenses? Why do the patterns differ? Some "lenses" are present in shallow-water species whereas others are present in deeper water species! And how are the patterns adaptive? If that's indeed the case? 

Many, MORE questions! and probably at least one more post about these newly discovered animals! 

Tuesday, May 16, 2017

Tremaster mirabilis! Five things I have learned about a Fantastic Starfish!

Baker Island
Back in 2008 I wrote a post about a great looking starfish that I wanted to know more about, a weird looking deep-sea star called Tremaster mirabilis!  

Its a striking looking animal and its not unusual for odd looking animals to have some kind of story attached to it..and as we learn more about it, the more intriguing it becomes! 

The species name "mirabilis" is Latin for "wonderful" or "to marvel at" and as we'll see the genus name Tremaster has an equally appropriate descriptive etymology! 

Since I wrote that introductory post in 2008 not only have I learned more about it-but we've now seen it ALIVE all over the Atlantic and  the tropical Pacific thanks to the livestream videos of Okeanos Explorer!

Brief Introductory Details: Tremaster is a starfish in the family Asterinidae, that puts in the same family as "bat stars" and a bunch of other sea stars you probably recognize from shallow waters and home aquariums. Go read this account on this huge and diverse group, which I wrote a while back...
Bat star
image via Flickr by Ed Bierman
But one of the people I/we owe the MOST to is a diligent and smart-as-a-whip young researcher named Ms. Katie Gale (more at her website here) who was working in the deep-sea biology/ecology & reproductive biology lab of Dr. Anne Mercier at Memorial University in Canada! 

Katie published this great paper on feeding biology and ecology of deep-sea asteroids collected off the coast of Canada in the North Atlantic in Deep-Sea Research in 2013.  I blogged it up here.

During the course of Katie's research she collected a fair amount of cool "anecdotal data" which amounts to singular observations and some other stuff which furthers the "natural history observation" of a starfish about which we know very little!   So her observations along with some further observations from the 2017 research legs of the NOAA Okeanos Explorer, some further homework on my part and voila!

Let us learn MORE about the weird starfish Tremaster mirabilis!

1. It eats coral (possibly)
Probably one of the BIGGEST questions I had for such a strange looking sea star! As we'll see, this species is seen quite a bit and yet one of the most immediate questions about it seemed elusive!

Fortunately Katie Gale was quite lucky and was able to capture and image of this specimen of T. mirabilis taken by the fine people who operate the Remotely Operated Vehicle ROPOS/DFO. Gale's paper cites this image showing our mysterious starfish feeding on CORAL! 

Specifically the octocoral Acanthogorgia!  
Tremaster mirabilis occurs widely around the world and of course, its always possible that there is variation in feeding or that possibly the animal in the picture has somehow been caught doing something completely else that we have no clue about-BUT our best guess is that its feeding. So, we continue on with that notion..

BUT we have THIS image taken on Whaley Seamount during Leg 3 of the Okeanos Explorer mission at 875m!

Could its location on the rock surface be because its near a yummy food source? Another coral predator to add into our understanding of deep-sea coral ecosystems???

2. Time lapse movement and?? 
This probably seems like a common sense thing-we KNOW starfish move albeit VERY slowly. and can actually show some behavioral complexity (here) 

Katie nabbed some of this GREAT video showing this species moving around its aquarium and more importantly NOT attacking this sea anemone in the aquarium.

This is actually an important point because we know MOST starfish CAN move but they often don't.

So, ACTUALLY capturing it doing so gives us some insight into what they do when we aren't watching them..
Tremaster mirabilis and Flabellum
Katie for example caught THIS unusual variation in posture:  Could this be avoidance of the bottom somehow? Filter feeding? Some kind of stress response? 
Tremaster mirabilis
Note in this image that the "skirt" is lifted compared to the in situ Okeanos images below where the animal is flush with the bottom..
Tremaster mirabilis
What is it doing?? This is a bit of a A mystery. 

and on Pau Pau Seamount and elsewhere Tremaster  is CRAAZY abundant! Are they moving around to feed? to reproduce?  How does all of this come together??? These behavioral bits add to our understanding but also to the mystery!

If we sped the movement of this "constellation" of Tremaster mirabilis up, would we still see no movement? or  is it a Times Square of Deep-Sea Starfishes??? 

3. One species lives in at LEAST THREE Oceans?
It USED to be that everything we knew about this species was taken from museum specimens and indeed we are STILL dependent on samples from throughout the world for new records of where many species live.

There is some question about whether or not this one species "Tremaster mirabilis" is actually one species or possibly several 'cryptic' species disguised by the fact that all the individuals observed all appear to be the same.

 The external characters vary only slightly and its not unusual for a widely occurring species to demonstrate some... variation throughout its range. However, when we examine dead museum specimens we are often missing data such as color and behavior which can be important.  Especially when its range where it lives is at least THREE oceans!

Tremaster is a moderately occurring deep-sea species.. occurring roughly between 200 and 600 m

Thanks to submersibles such as Okeanos Explorer we now have VIDEO and ON SITE (in situ) observations of LIVING animals!

Tremaster mirabilis is supposed to be one species..but as you can see there is a SLIGHT difference in body form..

North & Central Atlantic: An image from Nygren Canyon (top) and the lower image from Puerto Rico. Note there's more of a "skirt" around the edge versus the Pacific ones.
Throughout the tropical Pacific
Here's a brilliant deep-orange one seen on the recent Okeanos leg from Jarvis Island..

And interesting brick colored one from Pau Pau seamount
and this interesting lighter colored individual from Baker Island..

Other Records show this species in New Caledonia and throughout the Pacific. I've not yet seen it from the Indian Ocean however..

Another place where Tremaster shows up? Antarctica and nearby...

4. There are Jurassic Fossils
As if dealing with living animals weren't enough, these intriguing beasts show a CLEAR relationship to at least TWO Jurassic fossils!

Bear in mind that the Jurassic is quite a LONG time ago. These sea star were living in the world's oceans while dinosaurs roamed the Earth!

AND like its modern descendents-these were quite spread out. Antarctica versus Switzerland!

Here's Protremaster felli, from the Jurassic of Antarctica! Described by Andrew Smith and T. H. Tranter in Geology Magazine 1985

and YET another "Tremaster" like fossil sea star, described in 1981 from the Jurassic of Switzerland: Mesotremaster  zbindeni described by famed Swiss paleontologist Hans Hess!
Image from the Wikipedia file:
Close up of the plate detail showing a familiar pattern for "Tremaster" like asteroids...

4a. Interesting Evolutionary History...  I had also mentioned briefly in my account of the importance of the family Asterinidae (here)  And well, Tremaster is possibly VERY important to the evolution of starfishes. It has a history showing them in the Jurassic.. and to those in the know.. these show a close resemblance to several weird deep-sea species! 

5. What does "Tremaster" actually mean? And"brood chambers"??
FINALLY! What does the genus "Tremaster" actually MEAN anyway? "aster" is obviously "star" but it turns out "Trema-" refers to "aperture" or OPENING!

When Addison Emery Verrill described this genus in 1880 he made allusion to these FIVE openings present in each interradius! These were one of the distinctive characters he used to diagnose his (then) new genus!! and "mirabilis" of course refers to "wonderful"

Here's a photo of the underside of a Tremaster specimen.. the openings are indicated by yellow circles!
So, as it turns out if you look more CLOSELY at these openings, they are actually OPENINGS into chambers present INSIDE and THROUGH the body wall and open up on the TOP:

Here are images of a dissected individual from the underside showing these openings (i.e. these are close ups of what's in the yellow circles above)
According to the author who described this species (and subsequent literature), there are actually BROODED young in these chambers! Its not clear to me if they are simply embryos or actual juvenile individuals. Strangely enough, these have not been least not in the literature that I could locate. and I have yet to actually spot them. But perhaps I've simply not been looking at the right ones...

Thus, the openings appear to provide an opening for water to circulate into these chambers which could serve any number of purposes.. Possibly to aerate the "brood" chambers? Or perhaps they assist in the degree of arching the dome-like shape is capable of??  Filter feeding? Predation??

One of the great things about science is how it marches on! Its been 9 years (!!) since I wrote that first post and I LOVE that what in addition to what I've learned from reading, there has ALSO been genuine progress in learning NEW information on the biology of these animals..  And one of these days we will more FULLY understand it and its strange signficance!

Also GREAT to see that animals like this INSPIRE! Here is a GREAT illustration of this species by "Cartoon Neuron" on Twitter...