Hello Annelidians:
I witnessed friday what was for me a most unusual phenomenon and I wonder if anyone in the group could have an explanation or been through a similar experience.
Hundreds of Eupolymnia magnifica (formerly recorded in these waters as E. nebulosa, until M. Londonio revision) were being beached along a stretch of beach in northern Quintana Roo, mexican caribbean. I saw them around 11:00am, but they were being washed out since about three hours, maybe more? The sea was extremely quiet and has been so for many days, there are no strong currents because this is inside the reef lagoon and temperature is high but as usual here. The organisms arrived with the wavelets, to be left aimless on the sand close to the seagrasses being washed as well (a lot of material from the seagrasses is washed on a daily
basis).
The worms, when collected, were still very much alive and moved well in the bucket where I put them, they measure from 7 to 15cm, and are intact with all their tentacles and branchiae...they seem perfect from prostomium to pygidium.
I went snorkeling in the whole area (not too deep, close to shore) to see if the rocks under which there are commonly found were turned around or something had changed in the bottom, but found all as usual.
No more beachings have been observed since, in that beach or any other in the vicinity.
In the scattered rocks or stones that lie underwater, even quite small ones, many Eupolymnia magnifica were found in their usual position, inside
their tubes and looking very healthy. Very few void tubes were found.
No one of those having lived around this beach for a long time ever noticed this phenomenon.
Could anyone comment? is there a reason or hypothesis to explain what was going on?
Thanks in advance for enlightening me
Wormly
Vivianne
Dr Vivianne Solis-Weiss
Head of Lab de Ecologia y Biodiversidad
de invertebrados marinos
ICML-UNAM
(presently staying at UNAM, Puerto Morelos, Mexican Caribbean)
-
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://www.bio.net/bionet/mm/annelida/attachments/20100913/8e5f2cfc/attachment.html
