Biology:Aspidodiadema

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Short description: Genus of sea urchins

Aspidodiadema
Aspidodiadema arcitum.jpg
Aspidodiadema arcitum
Scientific classification e
Domain: Eukaryota
Kingdom: Animalia
Phylum: Echinodermata
Class: Echinoidea
Order: Aspidodiadematoida
Family: Aspidodiadematidae
Genus: Aspidodiadema
Agassiz, 1879
Type species
Aspidodiadema tonsum
Agassiz, 1878
Species

See text.

Aspidodiadema is a genus of echinoderms belonging to the family Aspidodiadematidae.[1] The species of this genus are found in the Indo-Pacific and Caribbean.[2]

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.[2]

The ambulacral 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.[2]

The spines are slender and arranged in whorls. The lumens are filled with a mesh of horizontal dividers and vertical pillars.[2]

Species

The following species are recognised:[1]

References

Wikidata ☰ Q18583700 entry