Another in my sea egg series
Marine eggs in strings of 'jelly'
Third picture shows a Dog Whelk and two of its egg capsules.
No interactions present.
I am not quite certain these are Flat Periwinkle eggs, because I have not actually observed the process.
Worse, the web suggests that periwinkles may cast their eggs in capsules.
Both Flat and Common (Edible) Periwinkles occur here - I have NOT found eggs in small clumps.
You agreed...can you be so certain? Do you have experience with these jelly strings.
Can you give me a reference from the web say, or a book title? (I have only ACCampbell's Seashore book)
Apologies Dejay I fear my previous assumption's probably in error.
It was Collins pocket guide. sea shore of Brit & N'n Europe ISBN 0002199556 P.188 (out of print but prob. available in libraries. Like your quote it says common p's (L. littorea) shed capsules into sea; but flat periwinkles (L.obtusata) "oval/ kidney shaped, jelly encased egg masses".
But a 1937 Marie Lebour paper on 'prosobranch' eggs etc, pdf, 62 pages, http://sabella.mba.ac.uk/953/ has on p.128 similar description (but as L.littoralis) but gives size on average 7 by 3 mm, with 90-150 eggs, which seems too small for your eggs. She also describes these as 1 of the commonest egg masses but often mistaken for other species'.
(I'd also missed that they're laid on, eg, Fucus serratus). (the paper lists 12 sp's in jelly masses)
The only other possibility I could find was Calliostoma zizyphinum collins "long gelatinous ribbons" but Lebours "many times longer than broad, attached at 1 end & floating". Otherwise ophistobranches? (seaslugs etc)
is a good find for this very interesting topic.
I did some Google Scholar searches and this is what I have found in reputable sources so far:
Littorina saxatilis & L. rudis are ovoviviparous, L. nigrolineata has benthic eggs with direct development, L. nertitoides & L. littorea have planktonic eggs and larvae.
Littorina littorea sheds egg capsules directly into the sea. Egg capsules are about 1mm across and each biconvex capsule can contain up to nine eggs but normally there are only two or three eggs per capsule. (Marlin biotic).
Littorina obtusata lays whitish oval or kidney shaped egg masses on Ascophyllum nodosum, Fucus serratus and Fucus vesiculosus, and sometimes on rock surfaces. It takes up to four weeks for crawling young to emerge. (Marlin).
Gibbula cinerea eggs & larvae are planktonic.
Calliostoma zizyphinum lays gelatinous clumps though some references do say in ribbons.
I have now noticed some images on the web of mollusc eggs which are wrongly identified.
yes JoC, that's an excellent response. Well done and thanks.
I am still on this case and, sure enough, quite immature specimens of Topshell (Calliostoma zizyphinum) are present, adults seem rare.
I now have a few more pictures of close encounters with both egg-strings and Flat Ps. (Littorina obtusata) but ALL on rock surfaces.
To keep this subject alive, I may make another post in the next day or so.
Chris - I have that book now from the library and am hunting for a copy - it is very expensive!
Now, P188 shows a frond with eggs apparent. Whilst some of 'my' eggs are in fairly straight elongated clumps, others are curved.
This is the first time I have seen the picture and, had I have seen it before these discussions, I would have said that they are obtusata. But then all the clumps I continue to find are on rock surfaces.
These are far too numerous to be sea slugs'.
JoC is on the case too, as you see..
Oh good, you're human ChrisMcA!
I see that you've may also have stunned gramandy here - http://www.ispot.org.uk/node/320895
I have a sneaky feeling that mine ARE Flat periwinkle as there are few other such molluscs in abundance where I took the photos - apart from edibles.
Calliostoma zizyphinum is here but is NOT prolific enough for 'mine'; in any case I would have noticed them.
I am about to strike off down-tide, so watch for another posting.
Good stuff, FAR more valuable than Blind Posting! http://www.ispot.org.uk/node/319702 (Blinds)
Well good luck, & you might be right & Lebours inaccurate (or a misprint!) (I'll be away for a week)
....and found fewer but it was a different shore.
I am now thinking these strands MIGHT be Limpet - is that possible?
Edit..[No...I may have ruled that out the following day]
Like all these things, in the hour I spent looking and photographing, I found three other unidentified creatures!
and some breadcrumb-like sponges!
It is worth following Gramandy's post here -
I would be surprised if these were L. obtusata eggs. It would mean that everyone from Lebour onwards has recorded and posted images of some other organism's eggs under the wrong heading. Marlin included, which would surprise us all. Marlin gives this in 'Additional information' Littorina obtusata lays whitish oval or kidney shaped egg masses on Ascophyllum nodosum, Fucus serratus and Fucus vesiculosus, and sometimes on rock surfaces. It takes up to four weeks for crawling young to emerge.
Nor do I think C zizyphinum is the answer. I am continuing to search for a match for 'your' eggs, posted here,
Yes Jo ...
I appreciate your continuing interest.
See the note I have just written to Chris (No Help).
I have to accept all that you say and the external evidence but my heart wants to accept Flat Perwinkle - bless them!
In some of my close-ups one can see little, very pale embryonic shapes.
I should collect some and play mother!
....well, after all this time I am coming 'round to thinking that these MIGHT be the eggs of the Red Ribbon Worm, Lineus ruber.
That would be a huge thinking-leap because they REALLY look like mollusc eggs! They are so numerous here that, surely, I should have seen a parent.
See - http://species-identification.org/species.php?species_group=macrobenthos...
EggPics here - http://www.aphotomarine.com/worm_lineus_ruber_ribbon_worm.html
I need a comment or two (JoC, Chris - anyone) before cheering!
I have added an ID - iSpot thinks it likely - ha!
Looks like a good match, especially as both yours & aphotomarine's show spirorbis for size comparison.
...well Chris, that was smart. I had expected you to be a bit more cautious.
I think we are right here but there are hundreds of worm-types and until I see one, near those eggs, I won't be satisfied.
I may leave the post title 'eggs in jelly' has that not quite certain ring!
The links certainly look like your specimen, but of the eggs of Lineus ruber, Hayward and Ryland p.154 says “Larvae 10 – 15 per egg string”. There are many per string in the photo. However Lineus viridis has 400 – 500 per string.... The internet postings of L. ruber eggs look like the ones we are interested in, but I am suspicious as they all have lots of eggs in them. No images for L. viridis eggs.
How about Calliostoma zizyphinum?
Fish and Fish say of this species: Yellowish coloured eggs are laid in gelatinous ribbons up to 35mm long and 3-4mm broad.
Earlier, after reading Lebour's paper, I thought not as she said ribbons attached in 3 places but that was to the aquarium glass.So now I am thinking Maybe. Unfortunately no internet photos of C. zizyyphimun either so far, just Lebour's diagram.
I haven't given up.
Oh that's good - you sticking with it. I appreciate it - keeps me going.
The number of eggs per string should be significant IF it amounts to a huge difference - it seems to.
You did this
Well, I was inspired so did this
I contacted Seb Holmes who studied Gamete release and Fertilisation in Calliostoma zizyphinum and he replied: “They aren't Calliostoma eggs and they do look suspiciously like Lineus ruber eggs to me. However, I have asked a colleague to confirm that they are indeed Lineus ruber eggs. I'll let you know once I hear.” And if I hear dj, you will hear.
H & R only have comments for the eggs of two nemetines, L. ruber and L. viridis, which differences I mentioned earlier; there are lots of other nemertines. The only on-line photo of any nemertine is on Photomarine L. ruber. It would be interesting to know if a worm was seen laying these eggs, or else by whom it was identified.
In the meantime - set up a marine aquarium, collect some egg cases, and note how many larvae hatch, and whether they go towards the light or not….
In Lineus ruber few (10-15) larvae of very variable size emerge from the egg-string after hatching and commence feeding immediately. They also exhibit a weakly positive, or, more usually, indifferent response to light which rapidly develops into a strong negative phototaxis. In contrast 400-500 small larvae emerge from the egg-strings of Lineus viridis and possess an initial period of strongly positive phototropism, lasting two to three weeks or more, during which they do not require food. http://species-identification.org/species.php?species_group=macrobenthos...
Well Jo (and Chris)
Who might consider arguing with Seb Holmes? He seems to have studied them closely.
But I'd probably trust your instincts, which are (were) for C.zizphinium.
I've spent ages on this and am coming 'round again to them being molluscan.
http://sabella.mba.ac.uk/889/01/Notes_on_the_eggs_and_larvae_of_some_Ply... on Page 1
Painted Top-shells are not common where I have taken the photos but Gibbula cineraria, Gibbula umbilicalis and Monodonta lineata are prolific - though I have yet to separate them properly.
There is SO little related to these very common strings of eggs. But here is a good reference
even an inconclusive picture.
Certainly Jo, the eggs strings seen associated with the Lineus worm pictures in Aphotomarine are THE ones BUT Dave Fenwick has admitted to recent egg-errors, but....
....we still HAVE to consider the egg-text here
We haven't reached the bottom of this yet; we should because they were so numerous and obvious.
Over recent months I have seen and handled quite a few marine 'red worms'
They all seem FAR too small to lay these gelatinous trails. There are number of larger worms, like the many Scale or Segmented worms (though "To avoid this [predation] the female scale worm retains the eggs after mating and thus prevents them entering the plankton. The larvae of scale worms are shed direct on to the seashore into crevices" http://www.gyllybeachfoodweb.org.uk/species-list/item/88-scale-worms )
but I can still find no clear evidence of association.
I am really surprised there are no other postings of these particular egg trails.
Eggs in jelly strings
"...Calliostoma deposits its eggs in gelatinous ribbons that are .." http://en.wikipedia.org/wiki/Calliostoma and (ignoring H&R) in A Student's Guide to the Seashore - Fish & Fish, this..of C.zizyphinium “…eggs are laid in long gelatinous ribbons about 4-5mm wide, each containing several hundred eggs and attached to the substratum..” Page 210
It has been a long haul and I have added the ID - to show I'm open minded.
But Jo. I know The Painted Top shell - there is NO way it could lay eggs underneath some of the stones where I've found these.
Lat/Lng: 58.92012, -3.156456
OS grid ref: HY335042
Mid to upper tide zone. Tide halfway out. Rocky shore generally, sandy below MLWS.