FAQs about Sea Cucumber Identification
Related Articles: Sea
Scavengers, Sand Sifters
Related FAQs: Cuke
ID 1, Cuke ID 2, Cuke ID 3,
Cuke ID 4,
Cuke ID 5, Cuke ID 7,
Cuke ID 8,
Cucumbers 1, Sea Cucumbers
Behavior, Cuke Compatibility,
Cuke Selection, Cuke Systems, Cuke Feeding, Cuke Disease, Cuke Reproduction,
Don't think this is a medusa worm?
I have dry rock 2 inch sand bed tank is 4 months old 160 gal. 30 gal fuge
skimmer 10 gal Chaeto tumbler. I suddenly have these worms. I'm sure it was a
hitch hike off Chaeto. No one can tell me good or bad (. Please help before I
have hundreds of them.
<Does look like one. In which case, is more related to sea cucumbers
than to sea worms; these are generally peaceful scavengers, I wouldn´t
worry as they pose no threat to aquarium inhabitants.>
Thanks in advance. Oh and what fish might
eat them? Copper banded butterfly maybe?
<If your tank is a fish only, you can try a Trigger fish, however If you have a
mixed invertebrate/reef tank, try using a trap with some bait like fresh shrimp
at night. My suggestion is to do this only if you see that they start to
multiply or if you don´t want them at all in your tank >
Re: Don't think this is a medusa worm?
Thanks! Very much. Happy reefing
<You´re very welcome, nice weekend. Wilberth>
Id of worm/potential young sea cucumber
Got a frag of sps of a fellow reefer and found a couple of worm like creatures
that are very small on the bottom.
The guy i got the frags from has 2 cucumbers in his tank. To the best of his
knowledge no bobbit/eunice worms.
Wondering if you might be able to id or help out.
The large one in pictures is about 4mm long.
<Wow! No wonder your pix aren't cropped, crisp (highly resolved)... Likely are
Holothurians, but could be some type of worm. I wouldn't panic. Thanks for
sharing. Bob Fenner>
Re: Id of worm/potential young sea cucumber
Yes was very hard to get pics. Those were the best i could get.
So you would say safe to let loose in display?
<Yes; I would>
I figure if they are small holothurians the sand would be a benefit.
<Agreed. Cheers Adam. BobF>
Sea creature ID 1/17/18
I found this creature on the beach at Sorrento, a town on Port Philip Bay, near
Melbourne, Southeast Australia.
It looks like a sea cucumber, but I have searched the net, including your site,
and haven't found any that are white.
It measured about 15cm end to end.
Could it be an albino? Or not a sea Cuke at all, but something else?
<Looks too smooth to be a Sea Cucumber... my guess is on a worm group. Perhaps a
Cucs? Are they multiplying. 2/7/16
I'm new to the forum but have been reading your posts for years. A wealth of
info for the reader. Thank you. This (Florida Aquacultured) LR hitchhiker seems
to be multiplying. Arrived Thursday attached to a rock and didn't move. No
attempt to filter LS or (new dry) oolite, he just stayed attached to a rock
about a quarter of the way up in the tank. Yesterday I noticed
protruding ornamental-looking flowery tentacles coming in and out his rear end.
I thought he might be expunging his guts, but after looking online, guts (and
potential disaster poisoning) seems to be white sphetti-like strings (ruled out)
this is not what coming out of him. So I left him alone. This a.m. there are two
smaller versions of him where he was stationed and he's moved a few inches.
Mithrax crabs, stars, all other hitchhiking life seems unaffected by this event.
Upon inspection, I see two others of the same on the opposite side of the tank
perched high on LR. Those two seem to be attached by one end, one end sticking
<Are these things actually moving?>
I want to know what they are and if they are multiplying. They are not sponges
but seem to be some species of Cucs.
<Maybe one or t'other... if mobile, my guess is on the latter>
I think it's reasonable the two perched high on the rock, on the other side of
the tank, crawled there overnight and are not related to the first one which
moved a apparently left two small duplicates of itself.
I'm attaching photos for some visuals. I hope they display. This is the first
The first photo is the original hitchhiker. Note the flowery tentacles on the
(right) end. They move in and out.
<Strange... would you be willing to sacrifice one to dissect it?>
The second photo is the new small (hard to see in photo) duplicates.
The third photo are the two perched on end at opposite side of tank.
Unrelated most likely to the duplication event. For better ID of species.
This tank is newly cycling. Ammonia was 1.0 yesterday, Nitrites 0, Nitrates 0.
Today Ammonia 2.0, Nitrites 0, Nitrates 0, pH 7.9,
<Low pH from cycling>
temp 80 degrees.
Note: Because of the abundance of life on this live rock that is
I did a 10% water change yesterday and I'm considering the 10% water change
today. I understand it's unorthodox, but I don't mind cycling slower to preserve
all the life on this rock.
<I would keep changing water; trying to keep ammonia under 1.0 ppm, and
pH above 8>
<Thank you for sharing. Bob Fenner>
Re: Cucs? Are they multiplying. 2/7/16
Thanks for the reply. Yes, the original animal moved to a new location two
inches upwards on LR from where it resided for two days upon placing the rock.
The duplicates move very slightly like caterpillars sometimes move,
moving only one end, probing the water but stay in their spot.
They are soft and fleshy with (soft) short exterior tentacles and a dark colored
protrusion on one end.
<Strange. I'll admit, I've not seen this before>
The largest, 3" long x 1/2" thick "original" has a flowery ornamental curlyQ
hind-end that protrudes about a 1/2" at times. The exterior body tentacles
occasionally move, like a starfishes "feet" but not so much as to appear
actively searching for a food source.
One of the "duplicates" is about 1" long and "active" but remains stationary to
its place on the rock. There are two other "duplicates" less than 1/2" long that
look pod-like with definite dark protrusions on one end, their other end appears
"affixed" to the rock, in they have not moved from their position. I can see
than tiny life-like body movements, enough to appear alive. They are definitely
living creatures. None have shown interest in migrating to substrate. They
prefer to be on rock.
The two "newly emerged" specimens, which seemed to migrate into their current
upright position overnight are about 1 1/2" long, 1/3" thick, and are perched
like pineapples at the highest point in the tank. They are the farthest possible
distance from the "original" location wise. They were definitely not in that
location yesterday nor did I see them at all before this morning so I assume
these creatures are capable of climbing terrain and prefer it to sifting sand.
These two have rather pointy ends sticking upwards with no dark protrusions
showing. Their "base" end on the rock is thicker than their pointy tops.
I've found another, "vacationing" in a ledge.
The ones "sunning" (power compacts 76 watts total in 29 gal biocube) out in the
open and viewable, have snail-like short trunks. I don't know the scientific
term for this "snout". Photo provided.
They are all pink-gray in color and definitely the same species.
I will be happy to send one. Pls provide details. What cool thing will you send
to me? : )
<Heeee! Maybe my sister>
Note taken on water changes.
<I'd definitely keep them; but... what are they? Pennatulaceans? Some sort of
worm? New to me.
Re: Cucs? Are they multiplying. Cukes... likely in place from the get go
Bob, I don't want your sister, she won't fit in my 29 gal biocube.
<How 'bout if I throw in a car?>
The 1st attached photo is of the ornamental hind-end or mouth, whichever way you
want to look at it, of one of the "duplicates".
The 2nd photo is of another of these creatures cruising the glass.
To date, I have never seen one on the substrate. They prefer height.
<Are these... the second pic...sea mice? Aphroditids? Do see the Net re... Bob
<The group pic appears to be Sea Cucumbers, Holothuroids. B>
Good afternoon everyone :)
<Bri; ten megs of pix; really? They're too poor in quality, not
The other week when I was feeding my tank, I noticed an almost clear
worm coming from out of my rock. It looked like it was a feeding off of
<I see this in your .mov>
The mouth and body was shaped like the detachable end of the vacuum
hose, the circular mouth of it. I've Googled and Googled and
Googled trying to figure it out, but no luck :( thank you for any info
that you may be able to help me with
<Looks more like a small Holothuroidean to me than any worm-group. Bob
Re: Unidentifiable Worm
Thank you for your fast response Mr. Fenner:) I apologize for the picture
quality, as I took them and sent them through my iPhone and didn't realize
that it would be difficult to see. Once again thank you kindly, and I will
be Googling about these now lol. If I may have any other questions regarding
this, am I able to reply to this email?
<Ah yes. Cheers, BobF>