Tiny orange crustaceans on sponges, etc.

I saw these tiny orange spots crawling around on some sponges and coral, and couldn't figure out what they are. Any ideas? They look like some sort of crustacean, and are maybe 2mm long, each.

I'm no expert on these, but think they are some type of amphipod, copepod, isopod, or ????pod... I've seen some the same color and size as yours living on a huge sea cucumber. Kind of like fleas of the sea...

I've seen these (or what I think are the same things) before in numerous locations in Indonesia. Never was set up for hypermacro when I saw them, but I've looked at them through my magnifying glass. I've always assumed that they were juvenile crabs of some sort. You can get several hundred on one sponge (and none on other similar sponges in the same area), which suggests to me a recent mass hatching, or similar.

Robert Delfs

A guy I dived with - a marine biologist type - at Wakatobi in August confidently asserted they were isopods. He was working on the basis of my photos, since he said he had never realised they might look interesting until he saw my photos (and I believe he decided to shoot some in subsequent dives). But I haven't seen them identified anywhere formal.

I have also seen these in other places in Indonesia.

-David

Edit: for example, at Komodo:

Hey guys !

it's rather difficult to identify the crustacean group on these photos, I have never seen these critters before

I would say it's an ISOPOD rather than a larval crab, an amphipod or a copepod, but I would need a hyper-macro for confirmation

I am a bit puzzled by the strange (? posterior) orange expansions

hope we can soon elucidate this problem

cheers and

HAPPY NEW YEAR !

Art

When diving in manado a few years ago I remember seeing lil' guys just like these all over the place. At the time I thought they were either amphipods or isopods?

Assuming that the anterior appendages are antennae and not stalked eyes then it might be worth looking at the ISOPOD genus Santia?

Which is a rather Christmassy answer until someone comes up with something better!

Alex

Hey !

I don't think it's Santia, at least the Californian Santia hirsuta and a Caribbean species look quite different

these guys look more like this one from Guana (British Virgin Is):

http://www.nhm.org/guana/bvi-invt/bvi-surv...i04/h0705ax.htm

it's a very nice site for small Caribbean critters by the way, but most species are not yet identified (we're working on it)

I will ask a Japanese colleague working on marine isopods Santia, Munnidae etc. (maybe he also knows the tiny spider-looking and the red guys from Jervis Bay)

cheers

Art

Maybe someone out there can get a supermacro shot of one. I shot that using the 1Ds at 1:1, and cropped it down. I'll send mail to the Wakatobi folk to see if someone there can snap a shot.

I knew you would house your 1Ds.

Can you post some words on your experience with it?

Simon

Yeah -- I should do a proper review, which I will get to soon. I also will write about my experiences shooting Canon with INON strobes, and supermacro on Canon dSLRs.

The problem for me is seeing that small in the first place I'm gonna get a drop down magnifying scope fitted to the mask!

I'm pretty sure craig got shots of something similar in Lembeh or Komodo.

Hopefully we can comply and turn them into kodak moments in September.

Another angle, in case it helps. A rather drastic crop of a shot at Wakatobi.

-David

I have been doing my own research into this as it amused me that no one knew

You normally would have osmeone that knew on most dive boats I have been on ..

however

In my now half educated referenced brain I would put money down that it is actually a tiny giraffe found only in wakatobi and is highly endangered and should not be photographed using flash photography as this eliminates the sexual reproductive capabilities of these fine fine subaquatic pygmy giraffes

ok ok .. seriously I am going for Amphipods from that last photo .. the previous one was hard to decide on but now I am definately Amphipods although I cant find the website I saw the similar photo on . I just searched using google

although i did search all of the suggested creature to make my decision .. I may just have chosen the wrong one .. I'll inform later when i get home form work .. if you see this post edited .. it's cause i cheated !

They look like common cooties. Cooticus.whortoni to be scientific about it.

Thanks Jimbo, fame at last eh!

Good Job David, but are you sure that's not a dogs back

Thanks Jimbo, fame at last eh!

Everyone deserves their 15 minutes of fame!

Hey !

hmmm ... I am still not convinced that they are amphipods, it's possibvle though

amphipods usually have large coxal plates invisible here due to this strange brown-orange substance covering the body, which unfortunately also hides the segmentation pattern on the abdomen

also, critters on the third photo are fairly broad, amphipods are usually laterally compressed ..

I sent this photo to my colleagues yesterday, let's see what they say

by the way, I don't want to be a "moray eel" (see on the left) .. but .. let me think about my character .. a "jaw fish" !!!

Art

OK, folks I got the first replies from my isopod colleagues (one is from George Wilson):

#1

Hi Art

you are right, they are isopods. To me they appear to be a species of

Santiidae, the uropods being held up in the characteristic santiid fashion.

What is more unusual is the detrital (or other) covering of all the dorsal

surfaces.

#2

These Asellota are so covered with material that I cannot be certain. They are not, however, Munnidae because they have visible uropods. Specimens? Without inspecting them, I can't say for sure.

well, for the moment the consensus is Isopoda - Asellota, maybe Santiidae (but probably not genus Santia, see my message above), certainly not Amphipoda

cheers

Art

Hi folks !

two more replies:

Yes I thought that they could be Santiidae from the shape of the uropods, but they could also be one of the other little familes that accumulate crud like that, as well as some things we haven't described yet. I didn't want to say anything definite without more data. I would like to have specimens, if they can be gotten.

this one is from a Japanese specialist who described a new species in the genus Santia:

Thank you for your mail. They are isopods of Santiidae, maybe a species of the genus Santia. I could observed some essential characters of the genus from photos, these have long antenna 2 and robust uropods composed of protopod, exopod and endopod (In munnids and paramunnids uropods are very small, and in paramunnids antenna 2 is short.). Living santids look like red due to a large number of tiny red algae growing on the surface of body and appendages.

my compliments to Alex Mustard - he suggested first that it could be Santia !!!

although it's still not confirmed ...

my link to an unidentified isopod from Guana (BVI) - judging from these descriptions this isopod could be a Santia, too !!

best fishes

Art

Hi

the debate continues, although I am not sure that somebody really cares now ... I guess my monologue becomes quite boring ...

anyway, regarding the genus Santia my colleague George Wilson (Australian Musuem) replied:

I wouldn't think that genus name. I am only willing to suggest that they might be the family Santiidae, with the provisio that other families could have the same appearance (e.g., Janiridae, Pleurocopidae, or even a shallow water Dendrotiidae). Or even something that no one has described yet ...

the guy from Japan believes it's Santia, as is the isopod on my previous link, I sent him that photo and he replied:

Yes, it is a species of Santia, too. Only one species of the genus, Santia milleri (Menzies and Glynn, 1968) is known from Caribbean Sea up to now. To judge from the photo, I think it is just the species. But, there is a possibility of new to science

HEY GUYS !!! DON'T SLEEP !!! TRY TO CATCH A FEW OF THESE CRITTERS !

ciao

Art