Deep-Sea Echinoderms of New Zealand
Order Cidaroida — Family Cidaridae
Goniocidaris Agassiz & Desor, 1847
Goniocidaris umbraculum Hutton
- Hutton, F. W., 1879. Cat. Echin. N.Z., p. 10.
Material Examined: Thirty individuals, from the following deep-water hauls: 250–300 fathoms, Cook Strait, VUZ Station 53, 1 specimen; 200–300 fathoms, Cook Strait, VUZ Station 51, 2 specimens; 50–200 fathoms, Cook Strait, VUZ Station 54, 22 specimens.
The species has previously been recorded as ranging from Cook Strait to Foveaux Strait, at depths of 40–60 fathoms (see Fell 1954, pp. 40–41).
Subgenus Aspidocidaris Mortensen, 1928
Basal disc on primary radioles more or less developed, and terminal disc usually well developed, often forming large round discs which cover the whole apical side. Secondary spines flattened, with a straight-cut end.
The subgenus has not hitherto been reported from New Zealand. One species, Goniocidaris (Aspidocidaris) australiae Mortensen, is known from Australia, three occur in the Indonesian-Philippines region, and two others in Japanese waters. The New Zealand form is apparently different from any of those.
Goniocidaris (Aspidocidaris) parasol sp. nov. Plate 3, Fig. B, Plate 5, Fig. b; (both holotype).
Diagnosis: Test flattened above and below, the sides arched, ambitus rounded, apical system ca. half h.d., peristome one third h.d. Ambulacra weakly sinuate, ca. 16% IA. At the ambitus about seven amb plates occur opposite an IA plate. Interporiferous area 3–4 times broader than the poriferous area. Pores oblique. Marginal tubercles in vertical linear series.page 33
Internal tubercles 2 or 3 to each plate, in more or less vertical linear series. The median area is sunken, completely naked, and forms a conspicuous, vertical furrow, weakly sinuous but not following a zig-zag course, and with no abrupt changes in its width from plate to plate. About 7 IA plates. Primaries cylindrical, slender, developing a wide distal disc in the case of the adapical radioles; the disc is somewhat excentric, the adapical side being larger. In the adult, a fully-formed disc is almost as large as the apical area, and about 15 to 20 such discs may be present, forming a complete shielding system over the aboral surface. Oral primaries more or less spearhead-shaped, with lateral teeth sometimes evident near the base.
Material Examined: Five specimens from 130 fathoms, Station 34, Chatham Islands Expedition 1954.
Holotype: In the Canterbury Museum, Christchurch, H.d. 27 mm, ht. 17 mm. Colour in life, radioles pale purple or mauve, the secondaries and miliaries a rich red-brown. Test, when cleaned, creamy white.
Remarks: A fuller description, with photographic figures, will be given in the official report of the Chatham Islands Expedition. From the diagnosis above, it will be evident that the two species most similar to G. parasol are G. australiae Mortensen and the Japanese G. clypeata Döderlein. G. parasol is distinguished from both species by the greater development in the adult of the apical discs, by the broad, almost straight, sunken, naked furrow in the interporiferous area, with no trace of zig-zag furrows, by the colour of the primary radioles, and the arrangement of the internal tubercles on the ambulacral plates. From G. clypeata it is further distinguished by lacking the deckled edge to the disc, and by having the adapical side of the disc larger than the abapical side.
Ogmocidaris Mortensen, 1921
Ogmocidaris benhami Mortensen
- Mortensen, Th., 1921. Vid. Medd. dansk naturh. For., 73, 151.
Material Examined: Seventy-five specimens from the following deep-water stations: 400 fathoms, off Mayor Island, Bay of Plenty, Dom. Mus. Station B.S.210, 1 large individual (h.d. 30 mm, longest primaries 70 mm), and several juveniles; 290 fathoms, Chatham Rise, Station 59, Chatham Islands Expedition 1954, 1 specimen; 270 fathoms, off Mayor Island, Bay of Plenty, Dom. Mus. Station B.S. 209, 10 specimens; 200 fathoms, S. of Cape Kidnappers, Kotuku Station 5, J. A. F. Garrick, 1 specimen; 124 fathoms, Bay of Plenty, Station N.P.6, 56 specimens; same region, N.P.9, 2 specimens; 113–120 fathoms, off Mayor Island, Dom. Mus. Station B.S.208, 1 specimen.
Mortensen (1921, p. 151) drew attention to the fact that Benham (1909) had confused Porocidaris elegans Agassiz (now referred to the genus Histocidaris) and Ogmocidaris benhami; later Mortensen (1928, p. 76) noted that the erroneous record of Histocidaris elegans from New Zealand rested on this confusion. Whilst identifying echinoderms at the Dominion Museum recently I was surprised to find two specimens of Histocidaris elegans in the collection, one of them labelled "Ogmocidaris benhami", the other "Porocidaris". Both of the specimens were labelled as from "300 miles east of Cape Farewell, in 1,100 fathoms, H.M.S. Challenger". Reference to the Challenger Station list shows that, although a station (No. 165c) was worked "334 miles from Cape Farewell, in 1,100 fathoms", it was not a bottom-sample, and no echinoids or other bottom-dwelling animals are recorded as having been taken. On the other hand, at the preceding station, No. 164, off the coast of New South Wales, a number of specimens of Porocidaris elegans were obtained (the holotype included). Probably, therefore, the specimens at the Dominion Museum were derived from New South Wales, and the error in locality on the labels arose from a previous error in writing 165c instead of 164. It is not known how this Challenger material came to be deposited at the Dominion Museum, but it may be inferred that some exchange was negotiated when the vessel was in Wellington. A large pycnogonid in the museum of the Department of Zoology, Victoria University, is believed to have been acquired from the Challenger in this way.