Havelockia cf. quadruperforata ( Cherbonnier, 1954 )

Thandar, Ahmed S., 2019, On some lesser known sea cucumbers in the Natural History Museum, UK (Echinodermata: Holothuroidea), Zootaxa 4688 (3), pp. 361-381 : 375-376

Havelockia cf. quadruperforata ( Cherbonnier, 1954)

See synonymy above.

Material examined. 1991.11.12, Arabian Sea , Oman, 1 spec.

Description Specimen small, perhaps a juvenile, length 7 mm, breadth in mid-body 2mm, previously dissected (perhaps by Ms Ahearn) but main part of calcareous ring missing, damaged or under-developed, only fragmented processes of radial plates visible. Hence, tentacle number, form, size, etc. not determined in fear of an irrevocable damage to the specimen. Ventral tube feet restricted to ambulacra, dorsal feet scattered but more in ambulacra; anal teeth present. Gonadal tubules well developed but sex not discernible, due to juvenility of the specimen and their hardened nature as a result of previous drying up of the specimen. Body-wall ossicles, absent except for a few in the anal region where many partially corroded table discs, with or without a spire, occur. Similar tables with curved disc but with complete, two-pillared spire are present in some tube feet, with the pillars united at apex and ending in a single point. End plates absent. Tentacle ossicles comprise elongated rosette-like rods; introvert with similar deposits and compact, closed, mulberry-like rosettes, tables absent.

Remarks. This single juvenile is here tentatively identified as H. cf. quadruperforata because its anal ossicles to some extent resemble those present in this species, however, its tentacle ossicles are different from those of the type described by Cherbonnier (1955) and with the fragmented ones of the specimen above but similar to those of the Oman specimens from the NHMUK described above. Since its locality is identical to that of the NHMUK material there is no doubt about its identity. It is here opined that these forms from Oman deserve a new species status but this must await for more records of the true T. quadruperforata from Djibouti.