Astropecten primigenius Mortensen

• Mortensen, Th. 1925. Vid. Medd. dansk. naturh. For., 79, p. 272–4, Figs. 2–3, Pl. XII, Figs. 1–2.

Material Examined: Six specimens, from the following stations—250–300 fathoms, Canyon B, off east Otago, Dom. Mus. Station B.S.191, 1 specimen; 150 fathoms, Cook Strait, VUZ Station 98, 2 specimens; 105 fathoms, Mernoo Bank, Station 1, Chatham Island Exped. 1954; 61 fathoms, Mernoo Bank, Station 2, 2 specimens.

Mortensen's type was from 30 fathoms (north of Cuvier Island). The species has not hitherto been taken from deep water.

Astropecten dubiosus Mortensen

• Mortensen, Th. 1925. Vid. Medd. dansk. naturh. For., 79, p. 269–72, Fig. 1, Plate XII, Figs. 3–4.

Material Examined: 1 specimen taken by the Alert, 113–120 fathoms, off Mayor Island, Bay of Plenty, Dom. Mus. Station B.S.208.

The specimen resembles the holotype, but is a little larger, R 40 mm, r 9 mm. It exhibits the same features as those which distinguished the holotype from Astropecten imbellis Sladen, so that Mortensen's belief that the two species are distinct seems to receive confirmation.

Astropecten sp.

A young individual R 6 mm from 400 fathoms, off Mayor Island, Dom. Mus. Station B.S. 210, is insufficiently developed for identification. The terminal plate carries three prominent spines, much more robust than any developed on the marginal plates. The record seems to imply the existence of one other species of Astropecten in New Zealand abyssal waters.

The genus, not previously recorded from New Zealand or Australia, is characterized as follows: Disc large, the intermediate actinal plates in several series, of which the innermost continue to about the middle of the arm. Marginals of both series well developed. Furrow spinelets forming a comb. No pedicellariae. Madreporite covered by paxillae.

Plutonaster knoxi sp. nov. Plate 1, Fig. C, holotype.

Diagnosis: Each marginal plate of both series carries one prominent, robust spine, this spine being surrounded by small spiniform granules. Adambulacral armature comprising a furrow-comb of about 8 uniform spines, outside of which is a single large subambulacral spine. Actinal intermediate plates carrying 1–3 large spines, in addition to a general coating of small spinules.

Material Examined: About 30 specimens (some of them greatly damaged) from the following localities: 330 fathoms, Station 41, Chatham Islands 1954 Expedition; 61 fathoms, Station 2, Mernoo Bank. Chatham Islands Expedition.

Remarks: This notable addition to the New Zealand fauna is one of the interesting discoveries of the expedition in 1954 led by Mr. George Knox. The full description, with photographic half-tone illustrations, will appear in the official report of the Chatham Islands Expedition. As can be seen from the diagnosis, the species resembles the North Atlantic Plutonaster bifrons (Wyville Thomson) and, like it, is distinguished from other species of the genus by having only a single large spine on each marginal plate of both series. The adambulacral armature also resembles that of P. bifrons. The two species are distinguished, however, by the armature of the actinal intermediate plates. In P. bifrons the actinal intermediate plates carry in addition to minute spinules, a single large spine, whereas in P. knoxi there are from one to three large spines, these spines intergrading into the coating of spinules in the case of the distal intermediate plates

Holotype: In the Canterbury Museum, R 105 mm, r 33 mm.

Although recorded from Australia (on the basis of a single individual) Dipsacaster has not hitherto been taken in New Zealand waters. The genus may be characterized briefly as follows: The margin of the ray defined by the inferomarginals, which project beyond the superomarginals. Actinal intermediate areas large, crossed by fasciolar grooves. No pedicellariae. Madreporite large, covered by paxillae.

Dipsacaster magnificus (H. L. Clark)

• Lonchotaster magnificus Clark, H. L., 1916. Endeavour Rpt., p. 30, Pl. 6; Dipsacaster magnificus Fisher 1919. Bull. 100, U.S. Nat. Mus., 3, p. 150.

Material Examined: 25 specimens taken by Mr. F. Abernethy, honorary collector to Victoria University Zoology Department, at a depth of 55–63 fathoms in Cook Strait, 10 miles E. by S. of Cape Campbell. Colour in life, salmon-pink above, marginals paler salmon, underside cream.

Remarks: The holotype, hitherto unique, was taken by the Endeavour in the Great Australian Bight between 80–100 fathoms. The discovery of a relatively large population on the Cook Strait shelf, only a few miles from an area which had previously been trawled extensively, was a considerable surprise. Although D. magnificus has not yet been taken in deep water off New Zealand, it should probably be regarded as a deep water species, in view of its distribution. Like Psilaster, Gorgonocephalus, and other genera with a comparable range, it may well be an archibenthal type which occasionally ascends the slope to the continental shelf, provided the distance is not great.

Abactinal plates paxilliform, extending far along the arm in several series, usually more than one series reaching the terminal plate. An unpaired median but not recurved tooth common to each pair of oral plates. Adambulacral armature comprising a palmate group of furrow-spines and a co-ordinate group of subambulacrals. Numerous actinal intermediate plates. Marginal plates thick, robust, paired, with fasciolar grooves between them.

Pseudarchaster, though widely distributed, has not hitherto been discovered in New Zealand or Australia ("Pseudarchaster" boardmani Livingstone, of New South Wales, must be referred to Mediaster, as H. L. Clark (1946) has already shown). One deep-water species can be recorded from Cook Strait, and, by an unusual coincidence, a second sublittoral species has become known at the same time from the same area. For the sake of clarity both species will be diagnosed here, though only one of them is so far known from below the continental shelf.

Superomarginals, inferomarginals and actinal intermediate plates bearing granules, without enlarged spinules. Abyssal	P. garricki
Superomarginal plates bearing granules, but inferomarginal and actinal plates bearing both granules and coarse spines. Sublittoral	P. abernethyi

Pseudarchaster garricki sp. nov. Plate 3, Figs. G, K, holotype.

Description: Abactinal paxillae in crowded hexagonal or polygonal groups, largest on the disc, comprising usually about 7 polygonal granules closely arranged around a central polygonal granule, and with small angular grains filling in the outer margins of the paxilla.

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Marginals broad and short, the proximal ones about four times as broad as long. About 40 marginals from the interradius to an arm-tip. Both superomarginals and inferomarginals covered in a uniform, dense granulation of more or less hexagonal granules. No scales or spinules on any of the marginals. Adambulacral plates with an armature of 5 or 6 truncate, compressed furrow-spines, and 7 or 8 truncate subambulacral spines, similar to the furrow spines, but not compressed. Distad to these is another line of finer spines, 4–5 in number. These form a postadambulacral fasciole, in conjunction with a still finer series of spines carried on the proximal margin of the proximal intermediate plate. The intermediate plates otherwise bear only granules, with no enlarged spines.

Material Examined: Only the holotype, which is from 550 fathoms in Cook Strait, VUZ Station 101.

Remarks: P. garricki is apparently distinguished from all other species of Pseudarchaster by the complete absence of spines or spinules from the uniformly granulated marginals and actinal intermediate plates.

Holotype: In the Department of Zoology, Victoria University of Wellington. R 82 mm, r 26 mm. Rays 5. Colour in life, orange above, cream below.

Pseudarchaster abernethyi sp. nov. Plate 3, Figs. I, J, holotype.

Description: Abactinal paxillae in crowded hexagonal or polygonal groups, largest on the disc, tending to become transversely rectangular at the bases of the arms. On the disc the paxilla comprises usually about 30 granules, the central ones more markedly polygonal than the outer ones, which tend to be rounded, and are packed less tightly. Marginals broad and short, the proximal ones about three times as broad as long. About 42 marginals from the interradius to the arm-tip. The superomarginals covered in a rather fine, more or less uniform granulation, somewhat coarser toward the outer edge, and with the fascioles between the plates formed by finer granules in linear series. The inferomarginals densely covered in a scaly granulation, with occasional lanceolate, flattened spines directed distally from short stalks. Adambulacral plates with an armature of 3–6 (usually 4 or 5) cylindrical truncate furrow-spines, and about 12–16 truncate, cylindrical or compressed subambulacral spines; one of the subambulacral spines is usually much expanded into a flattened, or bifurcate, or sometimes lanceolate spine. Postambulacral fascioles indistinct. Intermediate plates armed with irregular granules, spines and occasional enlarged lanceolate spines, the borders defined by delicate spinules, arranged too irregularly to form obvious fascioles.

Material Examined: Fourteen specimens, including the holotype, from 55–63 fathoms, 10 miles E. by S. of Cape Campbell, March, 1957. Coll. F. Abernethy.

Remarks: From P. garricki this species is easily distinguished by the spines on the inferomarginal and actinal plates. P. abernethyi does present some close parallels to some other species, however. In particular it appears to fall close to P. parelii (Düben & Koren), a circumpolar north Pacific and north Atlantic species. To judge by Fisher's (1911) account, P. parelii has smaller paxillae, since the larger ones described by him have only half the number of granules found in P. abernethyi; this difference is further confirmed by Plate 31 in Fisher's book, a photographic plate which is clear enough to enable the granules in the paxillae to be counted. The material of P. abernethyi at my disposal shows considerable variation, especially as regards the adambulacral and actinal intermediate armature, but all specimens agree in having the larger type of paxilla which is present in the holotype. I therefore regard this as a primary diagnostic character. Pseudarchaster discus Sladen, from the Magellanic area, also invites comparison, but here again the paxillae are even smaller, having only "about a dozen" polygonal granules, according to Sladen (1889, p. 111). From P. dissonus Fisher the absence of bivalved postadambulacral pedicellariae provides a distinguishing feature, and the furrow-spines of P. dissonus are sharp, not truncate.

Holotypes In the Department of Zoology, Victoria University of Wellington. R 110 mm, r 32 mm. Rays five. Colour in life, orange above, the actinal surface cream.

Body covered by a membrane which is superficially smooth and rather thick, obscuring the underlying granules during life, though these become visible after drying. Secondary small abactinal plates on either side of the median carinal series. Actinal intermediate areas large, the intermediate plates polygonal. Adambulacral armature comprising a furrow-comb, plus granules or subambulacral spines and pedicellariae. No abactinal or actinal spines.

This striking Indo-Pacific genus, though new to the fauna of New Zealand, is already known to be represented in Western Australia, where a small species, A. dubius H. L. Clark, has been taken. The New Zealand representative, on the other hand, is a large and handsome form, rivalling Dipsacaster magnificus.

Anthenoides granulosus Fisher Plate 1, Fig. B.

• Fisher, W. K., 1919. Bull. U.S. Nat. Mus., p. 328, Pl. 88 and 94.

Material Examined: One specimen, taken in 270 fathoms, off Mayor Island, Bay of Plenty, by Dr. R. K. Dell, at Dom. Mus. Station B.S.209. It is now in the collection of the Dominion Museum, No. Z Ech. 567.

Remarks: The specimen, the only one so far discovered in New Zealand waters, appears to be an adult and has 31–33 marginals in either series, from the IR to the arm-tip. The holotype of the species was taken in 265 fathoms off Mollucca Islands. The New Zealand specimen has relatively longer arms, R 135 mm, r 50 mm, R = 2 6 r (as against R = 2 r in the holotype); this difference is, however, probably due to the greater size of the New Zealand specimen, for in other respects there is close agreement.

The marginals are densely granulated, with coarser granules on the lateral margins of the proximal inferomarginals. The ambitus is defined by the projecting inferomarginals alone. The pedicellariae are largest on the proximal adambulacral plates, and smallest on the abactinal plates, where they resemble cleft granules. The adambulacral armature is characteristic of the species as described by Fisher, comprising (a) a furrow-comb of 6–9 uniform, delicate spines, deeply placed in the narrow furrow, (b) 2 or 3 coarse sub-ambulacral spines, one or two of which become enlarged on the distal half of the arm, (c) scattered granules and pedicellariae. The enlargement of the subambulacral spines on distal adambulacral plates, though mentioned by Fisher (1919), was not figured by him, and so an illustration of the condition in the New Zealand specimen is given here (Fig. B). From A. epixanthus Fisher, of Hawaii, the present specimen differs in possessing abactinal pedicellariae and in its adambulacral armature.

The presence of this Indonesian sea-star in the Bay of Plenty gives further ground for regarding the area as falling within the Aupourian marine province, where northern elements of the fauna are most evident.

Subgenus Apterodon Fisher, 1940

Abactinal surface bearing cruciform plates whose lobes overlap, or are connected by intermediate plates, to form an open network of large quadrangular meshes. On the centre of each primary plate is a boss which carries a fascicle of delicate spinelets enclosed in united membranous sheaths. No pedicellariae.

The genus has hitherto been recorded from California, from Chile and from Antarctica.

Peribolaster lictor sp. now Plate 2, Figs. A, B, holotype.

Diagnosis: Body pentagonal-stellate, the rays truncate, flat below, rounded above. Abactinal armature of 3 (occasionally 4) slender spines, each about 2 mm long, in a fascicle, borne on a cruciform or occasionally triradiate plate. The lobes of these plates either overlap or less frequently overlie a small intermediate plate which carries no spines. Inferomarginal plates each carry one flattened spatulate spine. No actinal intermediate plates. Adambulacral plates not exactly opposite inferomarginals, each carrying a transverse row of flattened spines, decreasing in size toward the furrow. Oral plates each with three furrow-spines, the median one largest, and two recurved robust sub-oral spines. Tube-feet biserial.

Material Examined: Eight specimens from 130 fathoms, Station 34, Chatham Islands Expedition.

Holotype: In the Canterbury Museum, R 22 mm, r 9 mm.

Remarks: The species is easily distinguished from the other species with biserial tube-feet by having a total of five oral spines, of which two are sub-oral. In P. macleani Koehler there are four oral spines, one of them being sub-oral, and in P. biserialis Fisher there are four oral spines, all of them furrow-spines. In regard to the flattened or spatulate character of the inferomarginal spines P. lictor approaches P. macleani; the latter is an antarctic form. Peribolaster lictor is so called in reference to the bundles of rod-like spines which it carries.

A single row of marginal paxillae. Actinal intermediate plates extending only part of the way along the arm.

Crossaster japonicus (Fisher). Plate 2, Fig. F.

• Solaster japonicus Fisher, W. K., 1911. Bull. 76, U.S.N.M., p. 330.
• Crossaster japonicus Djakonov, A. M., 1950. Morskie Zvesdi Morei S.S.S.R., p. 74, Fig. 25.
• Crossaster multispinus Clark, H. L., 1916. Endeavour Rpt., Dept. Trade and Customs, Fisheries, N.S.W. 4, p. 66–7, Pl. XVIII, Figs. 5–6.

Material Examined: Seven specimens, from the following stations: 320 fathoms, Chatham Rise, Station 58, Chatham Islands Expedition, 2 specimens; 280 fathoms, Chatham Rise, Station 7, Chatham Islands Expedition, 2 specimens; 220 fathoms, Chatham Rise, Station 6, Chatham Islands Expedition, 2 specimens; 50–200 fathoms, Cook Strait, VUZ Station 54, 1 specimen.

Remarks: Fisher (1911) did not figure his material, but his description agrees extremely well with my material, save only that all my specimens have 11 rays, as against 10 or 9 for his. There are 28–29 marginals, separated by less than their own width in a regular series, their spinelets numerous (about 30), the peripheral spinelets shortest, all spinelets shorter than the adambulacral ones. The adambulacral armature comprises a furrow-series of about 9 webbed spinelets and a subambulacral series of 7 webbed spinelets, the latter rather longer than the furrow-series. In my material the spinelets are more closely united in the web than Djakonov (1950) shows in his East Siberian material, but this is possibly due to difference in mode of preservation. The oral plates have about 15 webbed marginal spinelets and about 9 webbed suboral spinules.

H. L. Clark (1916) has described C. multispinus from 150–230 fathoms off Tasmania, on the basis of four specimens, all of them 11-rayed like the New Zealand form. In general appearance the Tasmanian species resembles the New Zealand one, but the number of spinelets is less (6–8 furrow-spines, 7–9 subambulacral spines). The oral armature is similar. There are only about 16 marginal paxillae. Clark's material comprised smaller individuals than mine, R 40 mm, r 20 mm. as against R 85 mm, r 42 mm in a typical specimen from Chatham Islands Station 7. I believe therefore that the differences are due to age, and that the New Zealand and Tasmanian forms will be found to be identical, and that all should be referred to Fisher's C. japonicus, which is evidently a wide-ranging Pacific species.

Colour: The Cook Strait specimen, according to notes made from life by Professor L. R. Richardson, was orange-pink. The specimens from Station 6 of the Chatham Islands Expedition were a marbled translucent white and pink, when observed alive by Mr. G. A. Knox. All are faded to dull fawn-grey in alcohol.