Thyone imperfecta ( Cherbonnier, 1970 )

Thandar, Ahmed S., 2008, Additions to the holothuroid fauna of the southern African temperate faunistic provinces, with descriptions of new species, Zootaxa 1697 (1), pp. 1-57 : 7

Thyone imperfecta ( Cherbonnier, 1970)

Figure 3

Havelockia imperfecta Cherbonnier, 1970: 284 , fig. 3 A–T.

Thyone imperfecta Thandar, 1990: 215 , fig. 6.

Type MNHNP, EcHh 1486 .

Type locality False Bay , 34 o 18.8' S, 18 o 32.8' E, 60 m.

Material examined

SAM-A27980, UCT Ecol. Survey, False Bay , St. FAL 451 , 34 o 17.4' S, 18 o 39.2' E, 22.v. 1961, 67 m, 1 spec. plus fragment .

Distribution False Bay, WCP, 60– 67 m.

Remarks

This species is well described by Cherbonnier (1970) except that the introvert spicules were not examined. Thandar (1990) transferred the species from Havelockia to Thyone on the basis of its calcareous ring. Since then, several specimens, also from the UCT Ecological Surveys at False Bay, were referred to this species by Ahearn, but these records were not published. These records were verified by the writer and the body wall, tentacle and introvert spicules are here illustrated from specimen A27761 ( FAL 592W) from that material. The body wall table discs ( Figure 3A ) are large (56-82 µm, mean 76 µm), of various shapes and perforated by 10-12 holes; the podial tables ( Figure 3B ) are stout with a curved disc (63-100 µm, mean 77 µm) and a twopillared spire ending in 1-2 points; end-plates are absent. The tentacle spicules ( Figure 3D ) comprise scarce rosettes and numerous plates and rods, whereas the introvert is supported by rosette-like plates and true rosettes ( Figure 3C ). The single 60 mm specimen in the current material corresponds well with the type and the False Bay material here illustrated, except that no tentacle rosettes were detected. This species is well characterized by its large multilocular table discs in combination with 1-2-toothed spires of the podial tables, rosettes in the introvert and the absence of end-plates in the podia.

Figures

FIGURE 3. Thyone imperfecta Cherbonnier, 1970. SAM-A27761. A.Tables from body wall; B. tables from podia; C. rosettes from introvert; D. tentacle spicules. All drawn to same scale.