Thursday, October 13, 2016

New Species of Sea Stars from the North Pacific and BEYOND!



You may recall back in 2009 when I accompanied the Monterey Bay Aquarium Research Institute (MBARI) on a 10 day cruise exploring the North Pacific on the Juan de Fuca and Gorda Mid Ocean Ridges off the Oregon coast. Here was the cruise website.  I blogged about it here.
When we returned from the expedition I was VERY excited because we had collected MANY specimens and several were either new records of rarely seen species or outright NEW species!

I would like to give a big shout out to MBARI because almost EVERY thing they send me turns out to be a NEW species!  Here's a new coral-devouring star I named after MBARI geologist Dave Clague  and here was a poraniid starfish that was observed climbing up a black coral (antipatharian) to devour it

One of my favorite undiscovered starfish was this one, Paulasterias macclaini which I had to describe a whole FAMILY and genus in order to accommodate it!  This species was named for Dr. Craig Macclain, at Deep-Sea News, who had invited me on the cruise.


Well, describing that 6 rayed star took quite a bit of effort but there were many, MANY more species to understand!!!
We also collected many of the more 'non-descript' stars that we encountered as well as several others which turned out to be UNDESCRIBED species!! 

And YES its literally taken me almost 6 YEARS to get all of this done. As I've discussed before (here), it can sometimes take quite awhile for a species to be formally described.


The starfish I reported on in my Zootaxa paper are members of the Goniasteridae, the most diverse family of sea stars, which includes over 260 species in 65 genera!  Most goniasterids live in relatively deep-water (continental shelf and deeper) but historically, there haven't been many of them known from abyssal and lower bathyal (i.e., >1000 meter) depths.

Only recently have we been seeing better collections of these animals from these depths. As I've reported below, some were collected from below 4000 meters!

Sibogaster nieseni! 
The first few specimens of this species were collected by the Monterey Bay Aquarium Research Institute from Taney Seamount (off the coast of San Francisco) from abyssal depths (over 3000 meters!).

It is named for one of my former advisors from San Francisco State University: Professor Tom Niesen (now emeritus)! Author of the Marine Biology Coloring book and noted intertidal naturalist/ecologist along the California coast! 

He gave me my first shot at grad school and happily, his advice and instincts correctly guided me through my early years as a Masters degree student!
photo by J. Sharei
It seemed VERY appropriate to name this species, from off central California, after someone who has done so much to educate others about the significance of the invertebrates of the coast!! 

Interestingly, as I was in the process of writing it up, I suddenly became aware of multiple specimens of similar individuals from OTHER oceans in museums where I was NOT expecting to see them!

This one for example, turned out to be almost identical to the Pacific one I was working on but was from the tropical ATLANTIC! and even one from the deeps of Indonesia... 
Also, unusual is how, such a moderately big animal (about 4 to 5 inches in diameter) could have gone undescribed for so long?  But given how deep it was found (2100 to 4175 meters !) its been well "hidden"! 

This species is likely the deepest member of the Goniasteridae known.


Ceramaster pointsurae! 
This was a tiny little species that I think we collected as part of something else.. perhaps sampling sediment or some other part of the physical environment.

BUT it turns out that it is likely a new and distinct species with some resemblance to the shallow-water species of Ceramaster (aka the cookie stars) in shallow waters..

This species was found during my 2009 trip on the President Jackson Seamont at about 1975 meters! 

This species is named for the Moss Landing Marine Laboratories retired vessel, the Point Sur which was finally retired in 2014. 
I spent many a day sorting deep-sea invertebrates on the deck of the Point Sur and I was saddened to hear about its retirement.

Bathyceramaster careyi! New genus and NEW species! 
Figuring this one out required a bit of detective work, as it turns out...

Several years ago when I was working as a technician for the California Academy of Sciences, I had the pleasure of studying a newly deposited collection of deep-sea starfishes from Oregon State University.

It turned out, that one of the species in the collection was a rarely known species called "Mediaster elegans" collected by oceanographer Drew Carey. To the best of the knowledge of the workers at the time, it was thought that this was a new occurrence, since the original specimens were only known from South America (collected in 1905). 

But as it turns out, after comparing Carey's specimens with the newly collected material by MBARI AND the original type series (i.e., the specimens on which the species was based) it turned out there were actually TWO species present, "Mediaster elegans" (original name) AND this one!  And the one seen by Carey in 1972 was actually undescribed! So, what I'd argue was actually "Mediaster elegans" turns has not actually been seen until now...

and not only that, it had to be placed into a new GENUS in order to be correctly described! 

Boom! NEW genus described! New SPECIES described!
This species was ultimately found to occur throughout the North Pacific between 1700 and 3363 meter depths! 

With this one, named for Dr. Andrew Carey, formerly of Oregon State University! 
The gut contents described by Carey's paper in 1972 suggests that this species feeds on deep-sea sponges.

The paper outlines several goniasterids from the North Pacific at depths below 1000 meters, including several which have not been seen since their description. 

Now that the new genus Bathyceramaster has been described, I can also follow up with a note I made on one of the recent Okeanos dives to Wake Island! 

This white goniasterid we saw at about 2000 m MIGHT be Bathyceramaster, but I'd need to more closely examine the surface to be sure. But if the closeups of the surface texture were correct.. I think maybe??
New discoveries that lead to new questions!! 

What are they eating down there? How do they get so big? Why do some of these species always seem to be alone when you see them? 

My thanks to the Monterey Bay Aquarium Research Institute, the California Academy of Sciences'  Department of Invertebrate Zoology and the Museum national d'Historie naturelle in Paris! 

2 comments:

Bruce Thiel said...

So much yet to know...great pictures. Are those the type pictures used instead of descriptions?

ChrisM said...

These were just "off" images used from the paper. The formal paper includes the technical descriptions. Not included on the blog for various reasons..