Deep-Sea Echinoderms of New Zealand
This family is new to the New Zealand fauna, although it is known from Australia by a single species. It may be diagnosed as follows:
Tube-feet in two series. Rays more or less constricted at the base, usually numerous, sharply demarcated from the small central disc, and usually deciduous when handled. Abactinal skeleton of rays restricted to basal part. Long, slender marginal spines encased in skin, with numerous small adherent crossed pedicellariae.
Brisingenes Fisher, 1917
Papulae on the disc restricted to a ring about the margin, two papulae opposite the base of each arm.
The genus was founded to accommodate two species known only from the page 18Buton Strait, Celebes, at a depth of 559 fathoms (Albatross Station 5648). Its occurrence in New Zealand waters is therefore of considerable interest.
Brisingenes delli sp. nov. Plate 3, Figs. D, F, H, holotype arm, paratype disc.
Description: Disc covered with fine, conical, sharp granules about 20 to the square millimetre. Margin of disc rounded. Madreporite conspicuous, marginal, on a raised plate. Anus central surrounded by about 10 small spinules, twice as large as the granules of the disc. Rays 14, long (at least 200 mm in the holotype, paratype disc 25 mm in diameter). The genital region swollen, occupying about 30 mm of the arm's length, beginning about 30 mm from the base. Costae 15–17, of overlapping rectangular plates each carrying 2 or 3 triangular pointed granules. Proximal adambulacral plates about as broad as long, carrying 2 proximal furrow-spines, one proximal accessory subambulacral spine, one distal furrow-spine, and one primary subambulacral spine on the distal half of the plate. Occasionally the accessory subambulacral enters the furrow, making three proximal furrow-spines. The typical arrangement at the base of the arm is, by Fisher's formula (Fisher, 1919, p. 510):
Further out on the arm the number of furrow-spines is reduced to a single distal and a single proximal spine. At the base of the arm a lateral spine occurs opposite every third adambulacral; further out one is opposite every alternate adambulacral. The lateral and subambulacral spines are thickly spattered with minute crossed pedicellariae, looking like sand-grains adhering to the spines. The oral plates carry 1 actinostomial spine, a large, laterally directed proximal furrow-spine, a smaller distal furrow-spine, one long, slender, fluted suboral spine near the midline, and one short suboral spine near the distal furrow-spine.
Material Examined: Arms and discs of about five individuals, all taken by Dr. R. K. Dell at Dom. Mus. Station B.S.209, in 270 fathoms off Mayor Island, Bay of Plenty.
Holotype: An arm which, with a paratype disc, and also the rest of the material, is in the Dominion Museum Wellington.
Remarks: Brisingenes delli is distinguished from Brisingenes mimica Fisher by having only 14 (as against 16) arms, and only 15–17 (as against 25–30) costae The adambulacral armature is also distinctive. From Brisingenes anchista it is distinguished by the number of costae (40 in anchista), and by the adambulacral armature, the number of arms being the same in both species. Fisher (1919) points out that Brisinga bengalensis Alcock and Wood-Mason and Brisinga gunnii Alcock are 14-rayed forms whose exact systematic position is uncertain; they must therefore be considered as potential species of Brisingenes. Both of these forms have an entirely different adambulacral armature (see Fisher, 1919, p. 534) from the New Zealand material, and more numerous costae.
A family of deep-water asteroids, already recorded from Australia but not hitherto known from New Zealand. The familial characters include:
Rays five, long, stiff, tapering, with longitudinal series of abactinal plates, among which the carinals are prominent and carry a prominent spine. Primary plates prominent on the disc. Adambulacral plates of alternating large and small types, the large type projecting into the furrow like a keel, a keel on one side of the furrow occurring opposite a small adambulacral plate on the other side. Pedicellariae straight, never crossed.
Zoroaster Wyville Thomson, 1873
Plates of arm forming transverse, as well as longitudinal series, each plate covered by numerous small spinules or papillae, and usually bearing one enlarged spine. Mouth deep-set. Pedicellariae numerous, often large.
Zoroaster spinulosus Fisher. Plate 3, Fig. E.
- Zoroaster spinulosus Fisher, W. K., 1906. Bull. U.S. Fish Commission, 23 (3) p. 1102–4, Pl. 24, 41, 42.
- ? Zoroaster macracantha Clark, H. L., 1916. Rpt. Dept. Trade and Customs, Fisheries N.S.W., 4, p. 68–9, Pl. 28.
Material Examined: Two specimens, partly fragmented, from the following stations of the Chatham Islands 1954 Expedition: 280 fathoms, Chatham Rise, Station 7; 220 fathoms, Chatham Rise, Station 6.
Remarks: The spinules and papilliform granules of the arm-plates are apparently somewhat more attenuated and elongate than in Fisher's material, but in other respects the specimens agree closely with Zoroaster spinulosus. The species is especially distinguished by the adambulacral armature, and by the presence of one enlarged slender spinule on each of the plates between the superomarginals and the adambulacrals. These features are illustrated in Fig. E which was drawn from a section of the arm taken at the base in the individual from Station 7. The giant straight pedicellariae are a prominent feature of the spine adjoining the innermost (furrow-) spine. My material also appears to be conspecific with H. L. Clark's (1916) Zoroaster macracantha, from the Great Australian Bight, 250–450 fathoms. It agrees in particular in having a boss only on every second carinal plate in the distal part of the arm. As in Clark's material, the spines are nearly all lacking from these carinal tubercles. I consider that the characters by which he distinguished macracantha from spinulosus are variable and unreliable, and he indicates that in separating the Australian form he was influenced by the lack of material from the region between Australia and Hawaii (where Z. spinulosus occurs). That lacuna is now partly filled. The New Zealand material appears to be intermediate between the Australian and the Hawaiian types, but the differences are trivial and not of specific value. As I have not handled Clark's or Fisher's material the proposed synonymy given above has been prefixed by a question mark.
Opportunity will be taken in the official report of the Chatham Islands Expedition of giving photographic illustrations of the New Zealand specimens.
Sclerasterias Perrier emend. Fisher, 1924
Sclerasterias mollis (Hutton)
- Asterias mollis Hutton, F. W., 1872. Cat. Echin. N.Z. p. 4.
- Sclerasterias mollis Fisher, W. K., 1924. Bull. Inst. Oceanogr. 444.
Material Examined: Although more than a hundred specimens have already been recorded from the Cook Strait shelf at depths less than 100 fathoms (Fell, 1952, p. 12), only ten deep-water specimens have been received. This is the first evidence that the species is archibenthal.
200–300 fathoms, Cook Strait, VUZ Station 51, 1 juvenile; 150 fathoms, Cook Strait, VUZ Station 98, 6 specimens; 150 fathoms, Cook Strait, VUZ Station 99, 1 juvenile; 130 fathoms, Chatham Islands Expedition Station 34, 1 specimen; 120 fathoms, off east Otago, Dom. Mus. Station B.S.189, 1 specimen.
Allostichaster Verrill, 1914
Allostichaster insignis (Farquhar, 1895)
- Stichaster insignis Farquhar, H. Trans. N.Z. Inst. 27, p. 203, Pl. 13 (1).
var. gymnoplax var. nov. Plate 2, Fig. C, holotype.
Diagnosis: Resembling Allostichaster insignis, but differing from the typical form in having the broad supermarginal plates almost completely naked. The only armature they carry is a tubercle at the upper end of the plate, and two or three small pedicellariae. The granulated surface of the superomarginals (diagnostic of Allostichaster) is thus exposed naturally. Three papulae form a triangle between the naked lower ends of adjoining plates. page 20The armature of the inferomarginals comprises two flattened spines. The adambulacrals are as usual diplacanthid, and occasional monacanthid actinal intermediate plates are seen. These features are all illustrated in the figure.
Material Examined: A single individual, R 35 mm, from 120 fathoms, off east Otago, edge of Canyon A, Dom. Mus. Station B.S.189, 14/8/1955, R. K. Dell. The holotype is in the Dominion Museum.
Remarks: The specimen has only five arms, instead of the usual six, and only one madreporite. These characters would have led me to conclude that it is not fissiparous, were it not for the fact that two rays are only half as long as the other three. It is probable that the animal has undergone fission, but has not yet reduplicated the madreporite in preparation for the next division. One further ground for caution before considering that the specimen represents a distinct species is the fact that Benham (1909) records a specimen of A. insignis from off Otago, having the spines "less numerous than in typical specimens"—without more exact details, unfortunately; he also received a specimen with only five arms and no madreporite. The evidence thus seems to favour extending the diagnosis of A. insignis to include gymnoplax as a varietal form. Should it later be found to be a well-defined form, the varietal name will be available for specific ranking.
Cosmasterias Sladen, 1889
The genus is new to the fauna, but proves to be represented by the same species as in Australia. A diagnosis follows:
Abactinal plates forming more or less well-defined longitudinal series. Actinal plates in two or more series, not overhung by spines of the inferomarginals. Adambulacral plates diplacanthid. Large, straight, unguiculate (felipedal) pedicellariae present.
Cosmasterias dyscrita H. L. Clark. Plate 2, Figs. D, E. H.
- Clark, H. L., 1916. Endeavour Rpt., Dept. of Trade, Customs, Fisheries, N.S.W., 4, p. 71–2, Pl. 29, figs. 1–2.
Material Examined: Fragments of about 3 individuals, from 130 fathoms, Station 34, Chatham Islands Expedition.
Remarks: The holotype of this species was taken by the Endeavour in 200 fathoms, south of Gabo Island, Victoria, and until now no other specimen was known. As Clark has given only photographic illustrations of the whole animal, I am obliged to rely entirely upon his careful description in making the identification. The oral plates (Fig. H) carry four spines, namely an inner and an outer furrow-spine and a proximal and distal sub-oral spine. Small pedicellariae and large unguiculate pedicellariae occur on or beside these plates. The characteristic appearance of the unguiculate (or felipedal, as Verrill and Clark term it) pedicellaria is shown in Fig. D. The armature of the adambulacral plates is illustrated in Fig. E, occasional unguiculate pedicellariae occurring on the furrow margin. Smaller crossed pedicellariae are scattered among the spines. The actinolateral series carry either one or two prominent, coarse spines.