Taxonomic analysis of the genital plates and associated structures in Ophiuroidea (Echinodermata)
Author
Stöhr, Sabine
412800EB-AACE-4313-9810-61F89B740405
Swedish Museum of Natural History, Department of Zoology, Box 50007, 10405 Stockholm, Sweden.
sabine.stohr@nrm.se
text
European Journal of Taxonomy
2024
2024-05-14
933
1
98
https://europeanjournaloftaxonomy.eu/index.php/ejt/article/download/2525/11335
journal article
10.5852/ejt.2024.933.2525
2118-9773
11198874
8F720F2B-BFBC-4CA1-BFF2-A2B8C7C8D3E1
Genus
Ophiotypa
Koehler, 1897
Fig. 21M–P
Type
species
Ophiotypa simplex
Koehler, 1897
.
Examined species
Ophiotypa simplex
.
Oral GP
Absent.
Adradial GP
Cup-shaped convex, smaller than lateral arm plate to which it attaches. Articular structure a flat distal surface.
Abradial GP
Absent.
Oral shields
Not examined.
Radial shield
Single large plate above each arm base with two flat articular structures separated by a depression.
Remarks
Ophiotypa simplex
is the only species in its genus and strongly paedomorphic. Its disc consists of few large plates. Pairs of radial shields appear to have been fused into a single large plate or are replaced by the radial primary plates functioning as radial shields, but individuals with a pair of plates on one or several radii have been observed (unpublished data, Stöhr & Martynov). The ventral disc is covered by the large oral shield, genital slits are not visible and the abGP appears to be absent.