Other formats

    Adobe Portable Document Format file (facsimile images)   TEI XML file   ePub eBook file  


    mail icontwitter iconBlogspot iconrss icon

Deep-Sea Echinoderms of New Zealand



Family Astropectinidae

Astropecten Gray, 1840

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.

Psilaster Sladen, 1885

Psilaster acuminatus Sladen

  • Sladen, W. P., 1889. Rpt. on Asteroidea. Challenger Sci. Rslts., Zoology, 30, p. 225, Pl. 40, Figs. 1–2.

Material Examined: 32 specimens from the following localities: 430 fathoms, Cook Strait, VUZ Station 97; 380 fathoms, Cook Strait, VUZ Station 100, 10 specimens; 380 fathoms, Cook Strait, VUZ Station 96, 1 specimen; 200–250 fathoms, Cook Strait, VUZ Station 10, 1 specimen; 270 fathoms, off Mayor Island, Bay of Plenty, Dom. Mus. Station B.S.209, 1 specimen; 100–150 fathoms, Cook Strait, VUZ Station 15, 1 specimen; 113–120 fathoms, off Mayor Island, Bay of Plenty, Dom. Mus. Station B.S.208, 3 specimens; 124 fathoms, Bay of Plenty, NP Station 6, 13 specimens.

Remarks: The species was originally taken by the Challenger at Station 167, in 150 fathoms, north-west of Stephen's Island, and also off eastern Australia in 950 fathoms, and off South Africa, depth not stated. It is present in the Chatham Islands. page 5Expedition collections, but from shelf stations only; other specimens from the Cook Strait shelf have previously been recorded (Fell, 1952, p. 6).

Plutonaster Sladen, 1885

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.

Persephonaster Alcock, 1891

Persephonaster neozelanicus Mortensen

  • Mortensen, Th. 1925. Vid. Medd. dansk. naturh. For., 79, p. 415, Fig. 70.

Material Examined: Five specimens from the following archibenthal stations—155 fathoms, Station 40, Chatham Islands 1954 Exped., 2 specimens; 150 fathoms, Cook Strait, VUZ Station 98, 2 specimens; 100 fathoms, Mernoo Bank, Station 1, Chatham Islands Expedition, 1 specimen.

Remarks: The species is very common on the Cook Strait continental shelf, from 40 fathoms and deeper (see Fell, 1952), but has not hitherto been taken in deep water. It would appear to be a typical shelf species which occasionally lives on the upper fringe of the continental slope. It seems unlikely that the species will be found in the abyssal fauna.

Dipsacaster Alcock, 1893

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.

page 6
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.

Family Luidiidae

Luidia Forbes, 1839

Luidia neozelanica Mortensen

  • Mortensen, Th. 1925. Vid. Medd. dansk. naturh. For., 79, p. 278–81, Figs. 5–6, Pl. XII, Fig. 5.

Material Examined: Seven specimens from archibenthal stations, as follows: 100–150 fathoms, Cook Strait, VUZ Station 15, 6 individuals (fragmentary); 124 fathoms, Hauraki Gulf, NP Station 6, fragments.

The species has also been taken from various shelf stations between Hauraki Gulf and east Marlborough at depths from 35 fathoms and below. In addition to the deeper station cited above, the Ikatere took it at Stations NP 8 (40–125 fathoms) and NP 9 (60–100 fathoms), both in the Bay of Plenty.

Family Benthopectinidae

No representatives of this family have hitherto been recorded from New Zealand waters. The familial characters include alternation in the position of the superomarginal and inferomarginal plates, and the restriction of the papulae to definite areas ("papularia") at or near the bases of the arms. The tube feet have a small sucking disc. As the name suggests, the family is essentially a deep water group. The genera occurring in New Zealand waters may be distinguished as follows:

An unpaired interradial marginal plate present Benthopecten
No unpaired interradial marginal plate Cheiraster

Benthopecten Verrill, 1884

Benthopecten pentacanthus sp. nov. Plate 1, Figs. D, E (holotype).

Diagnosis: Superomarginals each carrying two spines, one of which is enormously enlarged on each of the five unpaired interradial supermarginal plates. Abactinal intermediate plates each carrying one, or occasionally two similar, spinules. Inferomarginals each carrying one erect spine, plus one or two secondary spinules. The unpaired inferomarginal carrying three larger and two smaller spines. Adambulacral armature of three furrow spines and two subambulacral spines. Oral plates each with four furrow spines, the median one enlarged, plus two suboral spines.

Material Examined: Two specimens, both from the same locality, depth 400 fathoms, off Mayor Island, Bay of Plenty, Dom. Mus. Station B.S,210, 28/2/1957, R. K. Dell.

page 7

Remarks: Both specimens are juvenile forms, as evidenced by their smaller size, and the fact that neither pedicellariae nor actinal intermediate plates arc developed. Benthopecten styracius Fisher, from Macassar Strait, would seem to be the species most closely related, and differences in the number of furrow spines (7–8 in B. styracius) and in the oral armature, could well be due merely to immaturity of the New Zealand material. However, Fisher expressly draws attention to the fact that B. styracius has only one spine on each supermarginal, whereas B. pentacanthus, despite its immaturity, already has two. Again, in styracius there are two inferomarginal spines, of which the uppermost is the longer, whereas in pentacanthus there are usually three inferomarginal spines, the lowermost being the largest. Another Pacific species, Benthopecten polyctenius Fisher, is somewhat similar, but lacks the five giant spines of the unpaired superomarginals.

Holotype: In the Dominion Museum, Wellington. R 5 mm, r 2 mm.

Cheiraster Studer, 1883

Cheiraster richardsoni sp. nov. Plate 1, Figs. F, H, holotype.

Diagnosis: Abactinal paxillae of both disc and arms having an enlarged central spine. Enlarged subcircular pectinate pedicellariae present on the abactinal surface, on the actinal intermediate areas, and occasionally also on the interbrachial marginal angle.

Description: Abactinal paxillae of disc and arms comprising 8–15 short spinules surrounding the central, enlarged vertical spine, in either a single or a double circle. Several enlarged pectinate pedicellariae on the abactinal surface of the disc (in the holotype there are three). Supermarginal plates forming a conspicuous border, each one broader than long, bearing a dense coat of erect spinules, and the interbrachial ones carry in addition a small erect spine occasionally. In the holotype there are 32 superomarginals in an interbrachial arc. from arm-tip to arm-tip. Inferomarginals broader than long proximally, but becoming longer than broad in the distal part of the arm. The proximal ones carry two (occasionally one or three) erect spines, on the outer surface, as well as the coating of erect spinules.

Actinal intermediate areas small, in the holotype not extending beyond the fourth adambulacral and second inferomarginal. Each intermediate plate bears one enlarged and several small spinules, except for the two interradial plates, which instead each carry five finger-like spines forming the comb of the pectinate pedicellaria. Adambulacral plates with a furrow prominence, bearing 6–8 furrow spines and 5–6 similar spines on the outer margin, together with one enlarged subambulacral spine. Oral plates each carrying about 9 furrow spines, the inner three much enlarged, especially the innermost one. The four suboral spines form a linear series on the actinal surface of the plate, the proximal one enlarged.

Material Examined: The unique holotype, from 400 fathoms, Cook Strait, VUZ Station 87.

Remarks. Cheiraster richardsoni falls in Fisher's grouping of species with an enlarged central paxillar spine, present on both disc and rays. From C. niasicus Ludwig it is distinguished by having pectinate pedicellariae on the abactinal surface, and from C. pilosus Alcock it differs still more, since there are apparently no pedicellariae at all in that species (see Fisher, 1919, p. 195). From C. inops it differs by having paxillae as numerous on the disc as on the arms, and by possessing pedicellariae. One other species, C. trullipes (Sladen) is comparable, as it has large subcircular actinal intermediate pectinate pedicellariae—however, C. trullipes falls in the grouping of species which lack the enlarged central paxillar spine.

Holotype: In the Department of Zoology, Victoria University of Wellington. R 31 mm, r 9 mm.

Family Odontasteridae

Odontaster Verrill, 1880

Odontaster benhami (Mortensen)

  • Peridontaster benhami Mortensen, Th. 1925. Vid. Medd. dansk. naturh. For. 79, p. 288–91, Fig. 8, Pl. XII, 12–13. Peridontaster benhami, Fell, H.B. Zoo. Pubs V.U.C. 18, p. 7, 1952.
page 8

Material Examined: Twelve individuals from archibenthal stations, as follows: 250–300 fathoms, Canyon B, off east Otago, Dom. Mus. Station B.S. 191, 8 specimens; 250–300, Cook Strait, VUZ Station 22, 1 specimen; 150 fathoms, Cook Strait, VUZ Stations 98 (2 juvenile specimens) and 99 (1 juvenile.)

Remarks: Other material seen includes 7 specimens from VUZ Station 55, on the Cook Strait shelf, 40–100 fathoms. Mortensen's holotype was taken from 20 fathoms in Foveaux Strait, and the species has otherwise been reported once, namely from 40 fathoms off east Canterbury (Fell, 1952, p. 7).

As Fisher (1940) was led to conclude that Peridontaster Koehler is a synonym of Odontaster Verrill the nomenclature of the species is here amended accordingly.

Family Goniasteridae

Until now three genera of Goniasteridae have been recorded from New Zealand waters, namely Mediaster, Pentagonaster and Nectria. Three more genera can now be added to the fauna, namely Pseudarchaster, Hippasteria and Anthenoides. In view of this major change in the representation of Goniasteridae the following key to the genera may be useful.

1. Body covered by a membrane which obscures the outlines of the underlying plates and granules; inferomarginals projecting beyond the superomarginals Anthenoides
Body not covered by a membrane which obscures the plates below; both marginal series similar 2
2. Paxillae on the abactinal surface 3
No abactinal paxillae 5
3. Abactinal plates with an elevated tabula, crowned with enlarged granules Nectria
Abactinal plates with unspecialized paxillae 4
4. An unpaired (but not recurved) median tooth to each pair of mouth-plates Pseudarchaster
No median unpaired tooth Mediaster
5. No abactinal or marginal spines; terminal marginal plates enlarged Pentagonaster
Abactinal and marginal spines present; terminal marginal plates not enlarged Hippasteria

Pseudarchaster Sladen, 1885

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.

page 9
Plate 2

Plate 2

A, B, Peribolaster lictor sp. nov.; A, abactinal skeleton and armature, midway along arm of holotype; B, oral, adambulacral and inferomarginal plates. C, Allostichaster insignis var. gymnoplax var. nov., supermarginal and inferomarginal plates. D, E, H, Cosmasterias dyscrita H. L. Clark; D, unguiculate (felipedal) pedicellaria from oral plate; E, adambulacral and actinolateral plates and their armature; H, oral plate, oriented so that the distal suboral spines are lowermost. F, Crossaster japonicus (Fisher), adambulacral plates and one inferomarginal, showing armature. G, I, Pteraster (Apterodon) bathami sp. nov.; G, oral plates and first three adambulacral wings, showing armature; I, paxillar spinules and webs of aboral surface.

page 10

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.

Mediaster Stimpson, 1857

Mediaster sladeni Benham

  • Benham, W. B., 1909. Rec. Cant. Mus. 1 (2), p. 94–7, Pl. VII.

Material Examined: Thirteen specimens from the following archibenthal stations: 250–300 fathoms, Canyon B, off east Otago, Dom. Mus. Station B.S. 191, page 112 specimens; 125 fathoms, Chatham Rise, Station 51 of the Chatham Islands 1954 Expedition, 11 specimens.

The species is known also from the Cook Strait shelf as a somewhat rare form at depths greater than 40 fathoms. Benham's holotype was a unique specimen from 25–30 fathoms off Oamaru, and apparently the species has not been recorded from any other locality till now. The Chatham Rise material presents some considerable variation in form, and this will be illustrated photographically in the official report of the Chatham Islands Expedition.

Hippasteria Gray, 1840

Hippasteria trojana sp. nov. Plate 1, Figs. A, G, holotype.

Diagnosis: Large pentagonal body, defined by conspicuous, naked marginal plates, each of which carries one prominent conical spine, 35 or 36 marginals in the entire interbrachial arc from arm-tip to arm-tip. There may be one or two large bivalved pedicellariae on the more proximal superomarginals and inferomarginals, and exceptionally there may be two sub-equal spines instead of one. The abactinal plates carry a single erect conical spine or a large bivalved pedicellaria, and they are surrounded by smaller platelets or granules. Actinal area large, with numerous large bivalved pedicellariae, each surrounded by a circle of granules. The pedicellariae form a row parallel to each furrow margin, on the adjoining intermediate plates. Adambulacral armature comprising 3 robust furrow-spines, which are flattened distally, and 1 to 3 robust, erect subambulacral spines, the number depending upon the size of the adambulacral pedicellariae. Typical patterns are illustrated in Fig. A, which shows the 5th to 7th adambulacral plates of a ray of the holotype.

Material Examined: The unique holotype, taken at a depth of 220 fathoms on the Chatham Rise, at Station 6 of the Chatham Islands 1954 Expedition. The full description and photographic figures of this species will be given in the official report of that expedition.

Remarks: H. trojana resembles H. spinosa armata Fisher in having naked marginals armed with 1 or 2 spines and pedicellariae, but differs in having 3 furrowspines (as against a single one in H. spinosa armata), and 1–3 subambulacral spines (as against 1 only). From H. heathi and H. falklandica, both described by Fisher, the New Zealand form is at once distinguished by the marginal plates, which are inconspicuous and granulated in the two species named, and carry up to 5 spines. The species to which H. trojana appears most closely related is the one which is most remotely situated, in the Atlantic Ocean—namely, H. phrygiana (Parelius). Both species have conspicuous, naked marginals; H. phrygiana 2–3 furrow-spines, not unlike the condition in H. trojana. However, a specimen of H. phrygiana in my collection can be distinguished by its blunt, cylindrical furrow-spines, which are not at all flattened distally. H. phrygiana also tends to have more than one spine on each marginal plate, whereas this is exceptional in trojana. A still more striking difference is the complete absence of pedicellariae from the marginals in H. phrygiana. It does seem evident, though surprising, that the New Zealand species is closer to the Atlantic species than to the Pacific or Magellanic ones, and it may appropriately take the specific name trojana, the Phrygians and Trojans having been close allies (Iliad Bk. 2).

Although no living species of Hippasteria has hitherto been recorded from Australia or New Zealand, it is relevant to note that a fossil form, Hippasteria antiqua Fell, was described from upper Cretaceous sediments in Canterbury (Fell, 1956), only 600 miles west of the position in which the living species has been found. Hippasteria antiqua carries a single robust conical spine on each superomarginal. The condition of the adambulacrals and inferomarginals cannot be determined, but one obvious difference from H. trojana lies in the prominent carinal abactinal plates, lacking from the latter species.

Holotype: In the Canterbury Museum, Christchurch. Rays five, R 105 mm, r 62 mm.

page 12

Anthenoides Perrier, 1881

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.

Pentagonaster Gray, 1840

Pentagonaster pulchellus Gray

  • Gray, J. E., 1840. Ann. Mag. Nat. Hist. VI, p. 280.

Material Examined: Although this beautiful sea-star is well-known from quite shallow water, 3–40 fathoms, it has not previously been taken from the continental slope. Seven specimens now in the Dominion Museum were taken by Dr. R. K. Dell from the edge of Canyon A, off East Otago, at Dom. Mus. Station B.S.189 in 120 fathoms. Dell (personal communication) considers it not unlikely that they had fallen into the canyon, as some shelf mollusca were found to be living under similar circumstances.

page 13

Family Oreasteridae

Asterodiscus Gray, 1847

Asterodiscus truncatus Coleman

  • Coleman, H. L., 1911. Mem. Aust. Mus. 4, p. 699, Pl. 83.
  • Powell, A. W. B., 1937. Trans. Roy. Soc. N.Z., 67, p. 78, Pl. 16.

Material Examined: Three specimens, two of them in the Dominion Museum, all received by courtey of Dr. Powell. None of them are from deep water, but the species is included here because it occurs in deep water (47–200 fathoms) off the east Australian coast and in the Great Australian Bight, and it is highly probable that deep-water examples from New Zealand will be discovered. The New Zealand specimens all come from the Hauraki region, Powell's first specimen being from west of Hen and Chicken Islands, in 29 fathoms.

Although H. L. Clark (1946) stated that nothing is recorded as to the colour of the species in life, Powell (1937) had in fact given a careful description, "ground colour of the abactinal surface chrome, heavily blotched with vermilion; larger tubercles and superomarginal plates mauve to dull purple; ground colour of actinal surface chrome with vermilion abactinal patches encroaching slightly at the margins; larger tubercles mauve, ambulacral regions pale grey to mauve". The colour of dried material which I have seen is a dark reddish-brown, dull yellow below.

Family Echinasteridae

Echinaster Mueller & Troschel, 1840

Echinaster farquhari Benham

  • Benham, W. B., 1909. Rec. Cant. Mus. 1 (2) p. 98–100, Pl. VIII.

Material Examined: Two deep-water specimens, one of them from 330 fathoms, the other from 290 fathoms, from Stations 41 and 59 respectively, of the Chatham Islands 1954 Expedition.

Remarks: Other specimens have recently been taken by F. Abernethy on the Cook Strait shelf. The species has, until now, been known only from Benham's holotype specimen, from Otago, 18–28 fathoms.

Henricia Gray, 1840

Henricia compact a (Sladen)

  • Cribrella compacta Sladen, W. B., 1889. Rpt. on Asteroidea. Challenger Sci. Rslts., Zoology, 30, p. 543, Pl. XCVI 1–2, Pl. XCVIII 3–4. Henricia compacta Mortensen, Th. Vid. Medd. dansk. naturh. For., 79, p. 307–8.

Material Examined: Five specimens from the following stations of the Chatham Islands Expedition, 1954: 280 fathoms, Chatham Rise, Station 7, 1 specimen; 220 fathoms, Chatham Rise, Station 6, 4 specimens.

Remarks: The holotype was taken by the Challenger in 275 fathoms, at Station 166, west of Cape Farewell.

Family Pterasteridae

This deep-water group, though widely distributed, has not previously been recorded from New Zealand. The familial characters include the following features:

Abactinal surface roofed over by a membrane, supported by the elongated paxillae, enclosing a supradorsal brood-chamber, within which the eggs develop. Water is drawn in through numerous small pores on the actinal surface and expelled through a central opening on the abactinal surface, termed the osculum.

page 14

Pteraster Mueller and Troschel, 1842

Adambulacral armature comprising a transverse comb, united by a web. Tube-feet in two series.

Subgenus Apterodon Fisher, 1940

Marginal oral spines not united in a web.

Pteraster (Apterodon) bathami sp. nov. Plate 2, Figs. G, I, holotype.

Diagnosis: Body thick and cushion-like, flat below, rounded above, subpentagonal or pentagonal-star-shaped in outline, the arm-tips turned upwards. Supradorsal membrane reticulated and bristling with the exposed tips of the paxillar spines, which support it; the paxillae usually having five (sometimes four or six) paxillar spines, the central spine not projecting, and not evident. Prominent central osculum, surrounded by a web. Adambulacral spines 6, the innermost one third as long as the outermost and the intermediate ones of proportionately varying lengths, all united in a web which adheres to the spine of the actinolateral membrane. Tube-feet in two series. Oral plates carrying 8 furrow spines, the innermost largest, the spines decreasing regularly in size from within outwards. The inner three spines are flat and spatuliform with an expanded tip, the others more slender but also flat. Suboral spine robust, recurved, sharply tapering from a broad base to an acuminate hyaline tip, longer than the innermost furrow spine of the oral plate.

Material Examined: The holotype, also photographs of a second specimen taken at the same station as the holotype, from 250–300 fathoms, off east Otago, Dom. Mus. Station B.S.191, Drs. E. Batham and R. K. Dell.

Holotype: In the Dominion Museum, Ech. 517, R 42 mm, r 28 mm. The paratype, held at the Portobello Marine Biological Station is a little larger, R 49 mm, r 35 mm.

Colour and Behaviour: Dr. Elizabeth Batham was able to keep the paratype alive at Portobello for two days, and has kindly supplied the following information: The colour in life was deep cream, or pale warm yellow, Munsell YR-Y 8/6, a uniform colouring without patterning. The osculum opened to a maximum diameter of about six millimetres for an interval of approximately 5 seconds, once every 1–2 minutes. As it opened, the disc rose up as a whole, becoming depressed again as the osculum closed, i.e., the opening and closing of the osculum is not just a local sphincter action, but involves the body as a whole. Particles of azocarmine pipetted over the osculum were vigorously squirted away as it opened, confirming that it is exhalent. During the observations, which extended over about 30 minutes, the temperature of the sea-water rose from 8.7° C to 8.9° C, but there was no obvious change in the respiration rate. The tube-feet at the tips of the arm were about twice as long as those along its length (about 1 cm long at the arm-tip).

Remarks: Pteraster bathami appears to be rather closely related to P. myonotus Fisher, from the Philippines, 74–279 fathoms (Fisher, 1919, p. 458). It differs as follows: The paxillae of P. bathami lack the central spine of P. myonotus, so that the reticular areas have a smooth floor; the areas also tend to be pentagonal rather than hexagonal, since there are five paxillar spines usually, not 6 (plus 1 central) as in myonotus. The adambulacral combs regularly comprise 6 spines in P. bathami (not 5), and the oral spines are more flattened. Fisher examined 8 specimens of P. myonotus, apparently none exceeding R 28 mm, r 24 mm, whereas both New Zealand specimens are much larger, and have relatively longer arms. If the New Zealand specimens were merely older examples of Fisher's species, one might well expect the arms to be relatively longer, and the number of adambulacral spines to be increased to 6—but it is extremely improbable that the number of paxillar spines would decrease with age, or that the central paxillar spine would be retracted. The best course is then to regard the New Zealand form as representing a separate species, closely related to the Philippines one.

From Australia H. L. Clark (1916) has described Pteraster tetracanthus, a species which evidently falls in Apterodon since no membrane connects the oral spines. This species is stated to have four adambulacral spines, and only four page 15oral spines; the pentagonal outline and narrow adambulacral armature result in relatively wide oral intermediate areas. All these characters distinguish the species from the New Zealand form.

Family Korethrasteridae

This family, usually regarded as transitional between the Pterasteridae and the Solasteridae, has not hitherto been recorded from Australasian seas. It may briefly be characterized as follows:

Abactinal side with paxillae formed by very long spines not covered by a supradorsal membrane. No actinolateral membrane. Marginal paxillae not enlarged. No oral interradial plates. Spines of the adambulacrals forming together with those of the lower marginals a single transverse series, not united in a web. Usually five-rayed.

Peribolaster Sladen, 1889

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.

Family Solasteridae

This family is here recorded for the first time from New Zealand, though it is already known in Australia, and a deep-water species was taken by the Challenger north of the Kermadec Islands. The family may briefly be diagnosed as follows:

Disc relatively large, bordered by marginal paxillae and carrying more or less prominent paxillae on the abactinal surface. Actinal interradial plates present. Adambulacral armature in two linear series at right angles to each other.

page 16
Plate 3

Plate 3

A, C, Pseudechinus flemingi sp. now; A, aboral plates of holotype, 52 mm h.d.; C, ambital plates of immature syntype, 26 mm h.d. B, Goniocidaris (Aspidocidaris) parasol sp. nov.; ambulacral plates. D, F, H, Brisingenes delli sp. nov.; D, oral and adjoining adambulacral plates; F, adambulacral and marginal armature, genital region of arm, distal border uppermost; H, costal plates. E, Zoroaster spinulosus Fisher, ambulacral, adambulacral and adjoining actinolateral series, showing armature and giant straight pedicellaria. G, K, Pseudarchaster garricki sp. nov.; G, abactinal paxillae; K, inferomarginal 5, adambulacral 7 and intermediate plates. I, J, Pseudarchaster abernethyi sp. nov.; I, abactinal paxillae; J, inferomarginal 5, adambulacral 11, and intermediate plates.

page 17

Crossaster Mueller & Troschel, 1840

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.