Echinoderms from Southern New Zealand
Peridontaster Koehler, 1920 — Peridontaster benhami Mrtsn., 1925
Peridontaster Koehler, 1920
Peridontaster benhami Mrtsn., 1925
- Off coast of east Canterbury, between Moeraki and Timaru, 40 fathoms, January, 1951; P. M. Ralph; one specimen.
Since Mortensen described the type specimen, the species does not, till now, appear to have been taken again. The type locality was east of the South Island, possibly the same area as that from which the new specimen originates. The latter was orange in colour in life, though now faded to pale cream. It measures: R, 32 mm.; r, 22 mm.; ratio R/r, 1·45.
In comparison with the relative abundance of the diplacanthid species of Asterodon, the two monacanthid forms, namely, P. benhami and Eurygonias hylacanthus, are rare. Indeed, whilst the above is only the third record of P. benhami, Eurygonias is so far known only from the unique genotype-holotype described by Farquhar forty years ago, now preserved at Victoria University College.