''Aspidodiadema'' is a genus of
echinoderm
An echinoderm () is any member of the phylum Echinodermata (). The adults are recognisable by their (usually five-point) radial symmetry, and include starfish, brittle stars, sea urchins, sand dollars, and sea cucumbers, as well as the sea ...
s belonging to the family
Aspidodiadematidae
The Aspidodiadematidae are a family of sea urchins.
Characteristics
All the members of the two extant genera, ''Aspidodiadema'' and ''Plesiodiadema'', are found in tropical seas at bathyal and abyssal depths, often on the submarine slopes of i ...
.
The species of this genus are found in the Indo-Pacific and Caribbean.
Description
The test is small and subglobular with fragile plating which is firmly tessellated. The apical disc is monocyclic. The plates membrane is embedded and does not touch the coronal plates.
The
ambulacral
Ambulacral is a term typically used in the context of anatomical parts of the phylum Echinodermata or class Sea star, Asteroidea and Edrioasteroidea. Echinoderms can have ambulacral parts that include Ossicle (echinoderm), ossicles, plates, spines ...
plating is pseudocompound with single large primary tubercle on every third plate which is much enlarged compared to the others. The primary tubercles form an alternate series down the perradius. These traits distinguish this genus from ''
Plesiodiadema'' and ''
Gymnotiara.'' The primary tubercles are perforated and notched. The secondary tuberculation confined to plate margins. The peristome has shallow, rounded buccal notches.
The spines are slender and arranged in whorls. The lumens are filled with a mesh of horizontal dividers and vertical pillars.
Species
The following species are recognised:
*''
Aspidodiadema africanum''
*''
Aspidodiadema annulatum''
*''
Aspidodiadema arcitum''
*''
Aspidodiadema hawaiiense''
*''
Aspidodiadema intermedium''
*''
Aspidodiadema jacobyi''
*''
Aspidodiadema meijerei''
*''
Aspidodiadema montanum''
*''
Aspidodiadema multituberculatum''
*''
Aspidodiadema nicobaricum''
*''
Aspidodiadema sinuosum''
*''
Aspidodiadema tonsum''
References
{{Taxonbar, from=Q18583700
Echinoidea genera