Okeanos Round up! Last week in the Papahānaumokuākea Marine National Monument!

the red stalked crinoid  Proisocrinus ruberrimus

So, sadly, the Okeanos Explorer's first leg has come to a close as it has concluded its survey of the 
Papahānaumokuākea Marine National Monument and the ship has gone into port at Pearl Harbor to prepare for the third leg of the research expedition starting August 28th, surveying the main Hawaiian Islands and Geologists Seamount!! YOW!

In the meantime I also wrote a Mission Log for the last leg about starfish here.

What sorts of COOL inverts did we see in the last 7 days?? Here are the ones that caught my eye...
1. Benthic Ctenophores on Sponges Galore! 

Many of you know that my blog showcases some of the most extraordinary examples of invertebrate diversity that I can find. I have talked before of my love of benthic comb jellies (aka ctenophores), which most people, if they experience them at all, encounter them in shallow water (here). 

Long story short: these are similar to jellyfish, most are swimmers, but some are specialized to living on the sea bottom or other substrates.

They occur in the deep-sea but are VERY poorly known there. Here are what are undoubtedly NEW observations. Possibly even a new species of these animals living on glass sponges between 1000-2000 meters!

Here's a tight shot showing only a few with their tentacles extended. These tentacles were actually measured by the folks on the ROV. They can get to be OVER A METER (3 feet!) LONG!

2. The Rare(ly encountered) starfish Pythonaster sp.!
Exciting to me was the discovery of one of the "holy grail" of deep-sea starfishes: A species in the genus Pythonaster! NOT PREVIOUSLY KNOWN FROM HAWAII!  Or for that matter, this far in the Pacific!!

We have seen a different species of Pythonaster in the Atlantic on previous Okeanos cruises (here), but those were known from older records. Not only were these new, but now we had pics of them FEEDING on a sponge!!    AMAZING!

NOTHING has been known about the biology of Pythonaster. In one picture, we now have MORE information on its biology than we've known since this animals' description in 1885!!!

Worldwide, there are less than maybe 10 specimens of this genus known!

3. A bizarre community of deep-sea tunicates, barnacle plates and...????
So, the last day the ROV from Okeanos Explorer was deployed they investigated a channel between west Nihoa and West Pac where the water current was quite strong.

They encountered sponges (of course!) but curiously also a number of other bizarre members that formed an unusual deep-sea community.

This community was made up of tunicates (Chordata-the same phylum to which humans belong!) aka sea squirts. These are filter feeders but not one of the usual species of tunicates one expects to find between 1000 and 2000 meters!!

These are those brown potato shaped things in the picture above. Note how they are all clustered together in neat, almost ordered serial rows.

Weird.

Also observed were these odd little yellow blobs, which formed long, reticulating networks. It was unclear what these were. Maybe more tunicates?? sponges??  

But they were ALL OVER the place!!  see all those long drippy yellow threads?? THOSE were all of those little yellow/gold blobs...

One other part of the mysterious west Nihoa community (and indeed all over the place): The  mystery of the dead barnacle graveyard??

Basically, it came down to the act that we were seeing these giant barnacle plates ALL OVER the bottom in HUGE abundance. Here's a close up, but you can see them above in the pictures.

But WHERE WERE THE LIVING ONES?

FINALLY the Okeanos Explorer team discovered them!! They were apparently giant deep-sea forms in the genus Chirona, But they were nowhere NEARLY as abundant as they were turning up in the barnacle "mounds". What happened?? Weird.

4. PURPLE CRITTERS!
Some animals in the deep sea are purple.

A purple squat lobster. Not sure if they got a name to it.

The stoloniferous octocoral Clavularia.

The gorgonian Victogorgia sp.

and this cute little jellyfish, which thanks to George Matsumoto at MBARI I know is called Crossota millsae!!

5. Nice Shots of the Slime Star Hymenaster!  But which one? 
I have written about the oh-so lovely and unusual members of the Pterasteridae before (here). And we see them in deep-sea habitats all over the world.

But in the Indo-Pacific there is a HUGE expanse with MANY, many more species to be considered!

Here is a species observed by Okeanos Explorer just a few days ago! The hole, which opens and closes is called an osculum.

and thanks to Steve Hornik(@shornik ) this VIDEO!

Purple slime sea star (video) #Okeanos pic.twitter.com/iXyTpN0fVt

— Steven Hornik (@shornik) August 17, 2015

I've studied Hymenaster in Hawaii before. This one, from an expedition I was on in 2001, was identified as Hymenaster pentagonalis, described by Walter K. Fisher in 1905

It emits a healthy defensive mucus!!

So, what is this purple one???

Or this ONE??  Deep Sea MYSTERIES!!???

Many other cool critters seen-but I leave you with an assortment of weird glass sponges....

What will the next leg of the Okeanos Expedition discover??

(More than!) Five Cool Things We Could See if the Okeanos Went Back to Indonesia

So, over the weekend, the livestream of Okeanos Explorer briefly mentioned and entertained the idea that they might head back to Indonesia for a revisitation of their inaugural expedition from 2010! (The INDEX-SATAL Mission). (I think someone mentioned the ambassador was on ship?)

That expedition was, of course, 4 years ago and the program had just begun. Updates were not as forthcoming. But an opportunity to RETURN to Indonesia? With the benefit of hindsight, experience and further preparation?? That would be awesome!

That area is known as home to probably one of the MOST diverse marine faunas of anywhere in the world.  And although there's a lot known from shallow and deep habitats, the deep sea areas (below 200 m) in the Indonesian area will likely make all the stuff R/V Okeanos Explorer and E/V Nautilus have been observing in the Atlantic look like a goldfish bowl by comparison! 

A LOT of the species in this area are likely undescribed. A veritable gold mine of biodiversity to be studied! Some of these taxa have no Atlantic members. (It would be even better if these were enhanced by collections of course!)

Here's some highlights that I would love to see again!  

1. The Sea Cucumbers

I don't think I've seen ALL the pics but the ones I have were brilliant. This red elasiopod would be something I think everyone should see again... 

Okeanos from expl2168

The oddball swimming sea cucumber with the big lobe: the appropriately named Psychropotes! 

From Okeanos expl5494

and this gorgeous swimming Enypniastes? Or something similar to it.. But wow! Transparent body! You can literally SEE the sediment filled intestine THROUGH the body wall!

from Okeanos expl5475

2. The Hydrothermal Vents

When people talk about hydrothermal vents, there's 2 or 3 places that register as the most iconic spots.. the Mid-Atlantic and the East Pacific Rise.  There's others but one vent site that no one really talks about much?  The ones surveyed by Okeanos in Indonesia! 

These are the hydrothermal vents found on the undersea volcano Kawio Barat (West Kawio) 

from Okeanos expl2184

Amazingly gorgeous spires created by hydrothermal activity. 0.5 to 1 meter tall active and inactive spires on the summit of the Kawio Barat submarine volcano. Spires observed at 1849 meters depth. 

From Okeanos expl2188

Further venting through some of these chimneys gives us these amazing structures covered by barnacles! 

from Okeanos expl 2195

What's that? you want to see those barnacles more close up? here ya' go...

fr. Okeanos expl 2196

3. The Insane Stalked Crinoid Diversity

One of the very interesting animals noted in the expedition pictures notes was the incredible diversity of stalked crinoids which were observed.. I've only shown two of them below..but the gallery shows many different types of stalked crinoids.. to say nothing of the feather stars (aka unstalked crinoids)

This red one, as identified by Dr. Marc Eleaume in Paris is likely Proisocrinus ruberrimus 

From Okeanos expl5403

 And an likely unidentified member of the Hyocrinidae...                                     

                            

4. Bizarre and wonderous Deep Sea Sponges (Hexactinellid or Glass Sponges? I think)
A wonderous cladorhizid carnivorous sponge from about 1000 m! 

from Okeanos expl5560

A bizarre sponge with unusual body morphology

from Okeanos expl 5599

5. And the underappreciated Slit Shell Snails (Pleurotamariidae)! 

I'm honestly not sure how many people recognized a majority of the animals observed on the 2010 dive but some of the shots from the NOAA Photo Library showed some awesome images of that most treasured of marine snails: The Slit Shelled Snail (family Pleurotamariidae).       

These snails have always held a certain appeal to shell collectors. The shells are known from the fossil record and have a distinct slotted opening near the shell's opening. They are one of the largest marine snails observed in deep-sea settings..

from Okeanos expl5650

 The images place the slit-shell moving into this gorgeous field of corals..                                  

From Okeanos expl 5648

Some of these snails are predators on echinoderms, such as sea stars and possibly serpent stars (ophiuroids). So, conceivably this one is about to feed...

From Okeanos expl5646

PLUS! those Hermit Crabs with shells replaced by sea 

anemones! 

fr. Okeanos 5671

fr. Okeanos 5672

ONE More GREAT thing?? In situ observations of WOOD FALL COMMUNITIES!  These are some of the weirdest, rarest of deep-sea habitats as written by Craig McClain at Deep-sea news as he's documented here and here.  What are they? Deep-sea communities based entirely on wood from the surface that have fallen to the deeps!!

Some of these species are known ONLY from wood substrates!

But how often do you get to see an established wood fall community??  Here's what looks like those wood-eating urchins I wrote about a few years ago...

Okeanos expl 5968

and here's a close up of some more urchins and polychaetes

from Okeanos expl 5972

and yeah, there was a LOT more...

So, Okeanos Decision Committee?? LET'S GO BACK TO INDONESIA!!!