Friday, August 21, 2015

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!

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!
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??

Friday, August 14, 2015

This Week in Okeanos! A digest of Hawaiian deep-sea invertebrates seen over the last week!

Over the last few days, the R/V Okeanos Explorer has deployed its Remotely Operated Vehicle, the Deep Discoverer into some of the deepest waters in the Hawaiian Islands region, specifically in the Papahānaumokuākea Marine National Monument!  Many of the study areas have never been studied before.

The Okeanos Explorer's primary objective here is to map and document the communites which form the habitat and primary fauna of this region. And so, a majority of their time goes towards studying the many, MANY deep-sea sponges and corals which make up these habitats. 

The main page for the NOAA Hawaiian Expedition can be found here.

Their LIVE feed can be found here.


I've been tweeting the LIVE stream of the Okeanos' various discoveries and last week I documented the many, MANY different types of glass sponges seen by the Okeanos Explorer

This week I thought I would just digest some of the various discoveries made which I thought warranted a place in today's post! Although most of the screengrabs here are mine, I am ETERNALLY grateful to the Facebook Underwater screengrab group! 

1. Is this the world's LARGEST KNOWN SPONGE??? (Glass sponge or otherwise??)

Here was a pic of the ROV Deep Discoverer NEXT to the sponge. it was approximately 3.5 m long X 2.5 m tall, that's about 11 feet x 8 feet LONG!
Sponges and corals are known as "ecosystem engineers" because they play host to numerous other species and essentially become huge hubs of biodiversity. Many, MANY other animals live on these sponge colonies: brittle stars, starfish, squat lobsters, etc. the list goes on...


SOMETIMES, the community is a little more permanent than others. Here's a shrimp which lives inside this "glass cage" sponge. This species mates and lives inside the sponge for the rest of its life...

This story, of the "Venus flower basket" which is a pretty obvious deep-sea invertebrate "love story" is seen in the genus Euplectella. One can find more accounts of this story all over, such as here. 


2. Starfish FEED on glass sponges!
You wouldn't think there would be much on a glass sponge to eat, being composed primarily of... glass (see last week) but there IS that syncytium, the weird cytoplasm like stuff that covers the glass skeleton and a starfish has gotta eat.. 

Some goniasterid that is not clearly identifiable..
A "wolf pack" of Henricia sp. approaching on and feeding on this fallen glass sponge..

3. There are multiple species of deep-sea starfish which feed on corals too! 
One of my primary research interests and one of my favorite things to watch are deep-sea goniasterid starfish feeding on corals. I worked on these for my PhD and have described several new species of these animals (here) and here.  and even here

In Hawaii, there are several species of coral-devouring sea stars. Many of them display a fairly prominent border of spines around their body...

Calliaster pedicellaris
                          
Evoplosoma, probably E. forcipifera
and a new species I described last year, Hippasteria muscipula

4. Special Weird Deep-Sea Treats! The Bottom-living or "dandelion" siphonophore!!
A siphonophore is a gelatinous animal that is a sort of colonial jellyfish closely related to the Portuguese man-o-war. Siphonophores are best known as swimmers in the pelagic or open ocean. In the deep-sea, there are some species which live near the sea bottom and float above the surface, dragging their tentacles along the surface..
If the weird beast above seems kinda familiar, you may have seen another species of this "dandelion" siphonophore in other news....such as this one from Africa which has been making the news rounds as a weird "spaghetti monster"

The mystery of the million barnacle plates! The bottom was littered with millions of barnacle plates, but WHERE ARE THE BARNACLES??
 We did see a few, but were they even the same species??

5. and my personal favorite..a sea urchin called Aspidodiadema hawaiiensis! A strange sea urchin that looks like the spider robot from Johnny Quest! I've mentioned these before in my post about HURL's deep-sea Hawaiian urchins
                       
These seem to move around via a combination of their tube feet and these long bowed spines which seem to extend to the surface.
Also of interest are the beak-like structures near the base. These are called pedicellariae and given how large and prominent they are, I would speculate that they are extended for defense. Perhaps to protect the tube feet??
I also love these animals because they resemble the "robot spy" from Johnny Quest! 
And yeah, post this week was a bit late. Laptop in the shop! More next week! 

Wednesday, August 5, 2015

Deep-Sea Glass Sponges of the Hawaiian Islands! Okeanos Explorer Sponge Digest!!

OKEANOS EXPLORER!! Since July 10th one of NOAA's primary research vessels has undertaken research in the Hawaiian Islands region, but it has only been since Sunday (August 2) that the Okeanos Explorer has begun live-streaming their video of the deep-sea (> 1000 m) bottom communities of the Hawaiian Islands. 


A lot of their research in the area involves studying and characterizing the bottom communities-that is the organisms which make up the life living on the deep-sea bottoms.

This includes a variety of colonial animals such as coral (actually a catchall term which includes different types of cnidarians such as sea fans, soft corals and antipatharians) and many, many different kinds of sponges!!
Sponges are animals, and although they are considered among the simplest they are FAR from the simplest to understand. Sponges, as a general concept, occur in the family tree of life just before proper body tissue have developed but just after cells have come together to act together as part of a greater body. There's a huge variation in the body plan of sponges but most typically use some kind of inorganic material to form a supportive skeletal structure. 

For example, one grouping: the Hexactinellida aka the "glass sponges" have skeletons which are made primarily out of lattices of silicon oxide, in other words.. glass. 

Glass sponges are weird. In addition to their glass skeleton, which is demonstrated here in the shallow-water Euplectella
Venus' Flower Basket (Euplectella aspergillum)
Their skeleton is composed of the skeleton which is covered by an organic substance known as a syncytium. A syncytium operates at nearly a cellular level being composed of amoebocytes (i.e. independent cells) rather than formally developed tissue. 

In spite of their relative simplicty, the skeletons are complex and there's a LOT of variation in hexactinellids. They live in shallow and deep water. Mostly deep. There are over 500 species ranging from relatively shallow habitats to deep-sea habitats in 2000 to 6000 meter depths!

A LOT of these glass sponges are members of deep-sea habitats!  Here's a pic of the sea bottom at about 600 m or so? From off the island of Kona. These are ALL glass sponges. and each of those stalks anchoring them into the sediment?? Glass. Practically fiber optic cable! 
The Okeanos Explorer has been seeing a LOT of these glass sponges! They form an extensive part of the deep-sea habitats in the Hawaiian Islands region.

Some, such as this one called Regadrella has a more vase-like shape..
BUT the opening (called an osculum) is covered with an intricate glass covering called a sieve plate..
Others like this new genus/species is just kind of crazy looking. LOTS of weird textures and interesting folds attached to a stalk.
Another one... but with a slightly different morphology I think..
One thing to realize is the two red dots: These are 10 cm across.  That means this thing is HUGE!
                           
Here was the dead broken stalk from another different species. A big one.

For size comparison, here's the stalk versus the ROV. EASILY 2m long! (6 FEET!)

This one gives you some idea of how the stalk looks on living glass sponges. These aren't the same as the one above..but general notion..

If by the way you've always wondered what the texture of these stalks might be like? go pull some fiber topics out of your wall! Did you know that glass sponges are actually studied as inspiration for better fiber optics?? (here)

Although most sponges are filter feeders, some of them, such as these inoccuous looking cladorhizid sponges are actually carnivorous!!  These are likely predators on other animals!  These were unknown in the Hawaiian Islands region and are a new record for this group!
If you'd like to learn more about predatory sponges, my friends at MBARI have a TERRIFIC video about them

Sponges are also interesting in that, although they are animals, they don't really move and often serve as habitat or perch for various OTHER animals...

Numerous little crustacea, such as shrimp and copepods such as the ones shown below inhabit these large glass sponges for example..
This feather star has seen fit to use this glass sponge, Farrea sp. as a perch for filter feeding
and of course OPHIUROIDS!! You can't have a deep-sea sponge assemblage without brittle stars! (in this case.. ophiacanthids)
What sorts of things will we see next week? WOO!