Hitcher duster spawning?

[c est ma]

This is just one of those common hitchhiker feather dusters. Of course they've been cropping up all over for years, but I'd never observed this till now. For a few days (not sure how long in all) the top of the worm tube looked like this:

 

 

 

Today it looks more normal:

 

 

 

Should I assume the little mass of "dots" in the first pics were reproductive matter/eggs?

 

(Sorry about the bubbles...need to adjust that...)

 

--Diane

[RayWhisperer]

Interesting.... Sorry, I have no idea.

 

Look at the duster to the lower left in the first 2 pics. Is that thing attached to it? Maybe it is the opposite sexes reproductive organ.....??????

[c est ma]

I'm glad someone else finds this interesting...

 

Well, your query made me wonder--I've often noted those other, bell-like appendages sticking out of some of these little worms, and somewhere along the line I picked up the idea that they were the worms' equivalent of opercula, or tube 'plugs.' Here's a shot of another worm of mine that shows this organ well:

 

 

So I decided to look around online & see what I could find. One of the first things I found was a pic of a similar-looking appendage, labeled an operculum, in this well-known article (scroll down to pic):

 

http://www.reefkeeping.com/issues/2003-05/rs/index.php

 

Most sites only said "polychaetes broadcast their gametes directly into the sea."

 

In the process of searching, I came across this interesting article (has pics),

 

"Developing techniques for the artificial propagation

of the feather-duster worm

(Sabellastarte spectabilis) in Hawaii"

 

on page 4 of

http://www.ctsa.org/upload/note/RN_17_1632...39429490224.pdf .

 

This was the best description of duster reproduction I came across:

 

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http://animaldiversity.ummz.umich.edu/site...polymorpha.html

 

Eudistylia polymorpha

giant feather duster worm

Reproduction

Fertilization is external. The anatomy of the reproductive system includes gonads that are in back of the abdomen, bulging into the anterior part of the coelomic compartments, and two ciliated gonoducts which exit the coelom of each segment and open ventrally via gonopores near the abdominal fecal groove. Gametes accumulate in the coelomic spaces of the abdomen where they mature.

 

When mature, gametes enter the gonoducts, leave via the gonopores and are carried forward by cilia of the fecal groove. Palps with cilia, next to the first branch of each brachial stalk, transport gametes from the fecal groove to be released into the sea.

 

Sperm receptacles are known to occur at the base of crown tentacles in females of three species. In addition, free spawning also occurs in which individuals produce oocytes 140-200 um in diameter. (Brooding species produce oocytes over 200 um in diameter.) These are deposited in gelatinous masses on the tube or on sediment surface and are retained in a membraneous capsule tube.

 

Development to non-feeding pelagic trochophores and setigerous (segmented) larva is rapid. Settlement occurs in three to four weeks.

 

Many individuals have been found with characteristics of both E. polymorpha and E. vancoveri, implying that hybridization between the two species may occur.

 

(Fox 1994; Strathmann, 1987)

 

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I wonder if reproduction has even been observed and described in many of these species?

 

 

 

Sorry--TMI, I know!

 

--Diane

[RayWhisperer]

Damn you Diane, you always have the best pics!

 

Well, I didn't see any appendage similar to what you have. My eyes must be going now too. However, what you posted seems to confirm your thoughts on spawning.

 

These are deposited in gelatinous masses on the tube

[c est ma]

Gee, thanks!

 

You're right--that gelatinous mass thing might have been what I saw...somehow I didn't pay much attention to that part of the description the first time I read it!

 

It's funny how hardy & fecund these hitcher dusters are...so cool.

 

--Diane

[TimeKeeper22]

I just found one of those weird appendages on my feather duster! Now I know what it is! Thanks so much =)

I haven't seen any reproduce yet though lol

[Builder Anthony]

Thanks for posting i never knew thats how they lay eggs.I did see the bell thing before but thought it was there to stop things from coming into there place.