Atelostomata (oral plate pattern)
Description The two extant orders differ in the arrangement of the interambulacral plates posterior to the peristome that form the plastron: Left: Holasteroida: The elongated labrum (1) is connected to a single sternal plate (2) followed by two episternal plates. Right: Spatangoida: The narrow labrum (1) is connected to two enlarged sternal plates (2a/2b) followed by two episternal plates. The plastron carries large tubercles and strong spines specialized for locomotion within the sediment.
Scale 20 mm.
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added on 2009-02-23852 viewsWoRMS taxaScan of drawing Spatangoidachecked Kroh, Andreas 2021-02-24Scan of drawing Atelostomatachecked Kroh, Andreas 2021-02-24Scan of drawing Holasteroidachecked Kroh, Andreas 2021-02-24From reference Schultz, H. (2009). Sea urchins II: Worldwide irregular d...
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© 2009 Schultz, Heinke