Guianas nature forum

Other invertebrates - Andere ongewervelden - Autres invertébrés => Other invertebrates - Andere ongewervelden - Autres invertébrés => Topic started by: Auke on Mon, 02 December 2019, 04:35:05 AM

Title: Unknown organism | egg depositions Naticidae
Post by: Auke on Mon, 02 December 2019, 04:35:05 AM
Okay, here's a complete mystery to me, which is quite rare by now. A couple of days ago I found several dozen of these things on the beach of Braamspunt (eastside of the mouth of the Suriname River). I presume, for now, that these things have some animal origin, but it could just as well be something plant-based (or of yet some other origin). All of them were about the same size (4-5 cm in diameter), have a slightly wavy outer rim (curved down in the present position) and a somewhat funnel-shaped inner part (facing up here). The ones in the photo are all (nearly) complete; the wide gap in the circular shape is present in all specimens. They are rather floppy and tear easily. When drying out they become rather brittle but maintain their shape quite well. They appear to consist of uniformly very small sand particles (much smaller than what surrounds them in this photo), kitted together with something.

So, what kind of lifeform are these, or what lifeform produces these?

Cheers, Auke
Title: Re: Unknown organism
Post by: Auke on Wed, 08 July 2020, 09:34:02 PM
Solved! These are "sand collars"; the egg depositions of sea snails in the family Naticidae.

Cheers, Auke