Data: I found this little beauty while going through a sample of sand from Hawaii. I am working on my micro shells and I spotted this beauty. It is a "BIG" 2 mm. in diameter. Could it be a foraminifer?

Send Ideas to: Avril Bourquin

Discussions:

• That seems to be species of Echinodermata ( Sea Star or Holothuroids)
  Saludos, Jose H.

• The odd round object with lobes I don't think is a foram... haven't seen anything remotely like it, and banthics (anything about 2mm or more would HAVE to be a banthic ie bottom-dwelling foram) but it could possibly be an echinoderm ossicle. Forams always show signs of chambering, with an aperture. Not all show visible foramina (the tiny openings through which many protrude pseudopods). Benthics tend to lack foramina anyway. Andrew G

• The mystery object is a starfish skeletal element. I often see echinoderm and sponge skeletal elements mixed with "grunge" - some are quite beautiful. GTW

• I suppose these are the same as sclerites the "mysterious" critters from the Pre Cambrian and Cambrian. Emilio P.

• In regards to echinoderm ossicles:
  "One place to find them is on the Tree of Life web site www.tolweb.org
  Following the echinoderm branch to sea cucumbers leads to the Alexander M. Kerr page where photos of ossicles are included...Joan Jass"

• Concerning this item , the object currently ID'ed as an echinoderm ossicle, I strongly suspect that it is the benthic foram Calcarina. Calcarina is a relatively common foram of reef flat environments in the Indo-Pacific, but it most common in the south Pacific. If you are interested, I could look at my copy of the report on forams of Hawaii.
  Also, it just does not look right to be an echinoderm ossicle, either from a starfish or a sea cucumber.   T.Y.

Just a few of the WWW Sites investigated thanks to the help I received from the above contributors ideas:

• Web of Life:http://www.tolweb.org/tree?group=Holothuroidea&contgroup=Echinodermata

• Royal BC Museum: http://rbcm1.rbcm.gov.bc.ca/nh_papers/taxing.html

• Octocoral sclerites: http://www.calacademy.org/research/izg/sclerites.htm

• About Echinoderms: http://www.northwestdiver.com/creature_feature/echinoderms.php

• http://www.northcoast.com/~starfish/min-c.htm: "Echinoderms have been compared to living, moving castles. Castles are made of interlocking blocks, with a single main entrance and numerous slit windows for air and for defense. Echinoderm skeletons are made up of interlocking calcium carbonate plates and spines. This skeleton is enclosed by the epidermis and is thus an endoskeleton. Each skeletal element of an echinoderm is actually a single crystal of calcium carbonate, very finely branched and structured. "