Aquilonastra cepheus ( Müller and Troschel, 1842 )

O, P. Mark, 2006, A systematic revision of the asterinid genus Aquilonastra O Loughlin, 2004 (Echinodermata: Asteroidea), Memoirs of Museum Victoria 63 (2), pp. 257-287 : 270-271

Aquilonastra cepheus ( Müller and Troschel, 1842)

Figures 1, 2f–h, 5c–d

Asteriscus cepheus Müller and Troschel, 1842: 41–42 .— Dujardin et Hupé, 1862: 375–376.— Perrier, 1869: 99.

Asterina cephea .— Perrier, 1875: 315–317 (part; type).— Möbius, 1880: 50.— Döderlein, 1888: 825.— Sluiter, 1889: 307–308.

Asterina cepheus . — Martens, 1866: 85.—H.L. Clark, 1915: 95.— Fisher, 1919: 411, pl. 115 fig. 4.— Fisher, 1925: 79–80.—Liao and A.M. Clark, 1995: 130, pl. 15, figs 10, 11.— Rowe and Gates, 1995: 34.— A.M. Clark and Mah, 2001: 335.

Asterina burtoni .—H.L. Clark, 1921: 96–97, pl. 6 fig. 2.— Smith, 1927b: 276.—H.L. Clark, 1938: 144–145.—H.L. Clark, 1946: 133.— Marsh, 1974: 91–92 (non Asterina burtonii Gray, 1840 ).

Asterina burtoni cepheus .—A.M. Clark and Rowe, 1971: 68–69, fig. 17h, table 1, pl. 9 figs 4–5. — Liao, 1980: 171, figs 2:1, 2:2, 4, pl.4 figs 6–7.—A.M. Clark, 1993: 208 (non Asterina burtonii Gray, 1840 )

Aquilonastra cepheus .—OʼLoughlin and Waters, 2004: 11, 13–15.

Material examined. Holotype. Indonesia, Jakarta (as Batavia), M. Reynaud, 1829, MNHN EcAs1471 (dry).

Other material. Indonesia, Sulawesi, 2 Jan 2000 , UF 2623 ; New Guinea, Trobriand Group , AM J22934 (1); 1 Jun 1998 , UF 2332 (1); 1 Jul 1998 , UF 2415 (1) ; Philippines, Bohol I., 25 Mar 2004 , NMV F106973 (2) ; Australia, Queensland, Heron I., 14 Jul 1973 , F95594 (2); One Tree I., J23331 (1); Tryon I., 15 Sep 1970, F95789 (4); Northern Territory, Darwin, 11 Oct 1976 , F95799 (1); Western Australia, Abrolhos Is., 2 Sep 1972 , WAM Z6778 (7); J8321 (5); 11 Mar 1972 , F95793 (21); 12 May 1972, F95795 (6); Exmouth Gulf, F95794 (4); F95790 (2); F95792 (1); F95787 (1); F95788 (1); Aug 1972, F95790 (2); Quobba, 20 Jun 1972, F95791 (3).

Diagnosis. Non-fissiparous Aquilonastra species; rays 5, rarely 4 or 6, long, broad basally, strongly tapered, narrowly rounded distally, predominantly subequal, form sometimes asymmetrical; up to R = 25 mm; gonopores abactinal, some close pairs under same plate.

At R = 20 mm, r = 10 mm, abactinal plates angled up over papulae, crescentiform appearance; 0–3 proximal doubly papulate carinal plates; some large secondary plates, frequently 1 per space, up to 2; predominantly 1 papula per space, up to 3; disc frequently distinct, bordered by 5 large radial plates 5 small interradials; spinelets glassy, rugose, long, thin, finely pointed distally, not splay-pointed, subacicular, subsacciform to sacciform, up to about 32 spinelets in double series on large radial plates, up to about 24 in double series on proximal abactinal plates (frequently fewer), spinelets on anterior edge of plates, frequently angled over papula, sometimes in tufts; up to about 15 on mid-interradial plates; superomarginal plates with variably up to 8–10 spinelets per plate, inferomarginals with variably up to 16–24 thicker, longer spinelets per plate.

Spines per actinal plate variably up to: oral 6–9, suboral 2–8, furrow 6–8, subambulacral 4–8, actinal interradial 4–8; interradial spines thick, conical, blunt, subsacciform.

Colour (live). Wide range of mostly mottled colours with pink, mauve-red, grey, brown, grey-brown, reddish-brown, dark brown, black flecking, green, cream, white; disc frequently with broken white border (photos from N. Coleman).

Distribution. Indo-Malayan Region, Ceylon, Southern China, Philippines, Indonesia, W Pacific Ocean, northern Australia; 0–70 m (Liao and A.M. Clark, 1995; Marsh, 1974 as Asterina burtoni ; Rowe and Gates, 1995).

Remarks. As noted in the diagnosis, the numbers of spinelets and spines per plate is more variable than in other Aquilonastra species. The distinctive diagnostic character of A. cepheus is the thin long finely-pointed subsacciform spinelets projecting over papulae. Smith (1927b), Liao (1980) and Liao and A.M. Clark (1995) all noted this as a distinguishing character. OʼLoughlin and Waters (2004) redetermined as Aquilonastra cepheus a specimen from Hong Kong ( NHM 1981.2.6.25). It is redetermined in this work as A. limboonkengi (below). In his comprehensive synonymy for A. burtonii, Walenkamp (1990) showed the position of many authors who considered A. cepheus to be a junior synonym of A. burtonii . Liao and A.M. Clark (1995) restored the species status of A. cepheus . Asterina cepheus was reported for Thursday I. (N Australia) by Bell (1884, Alert collections); for Zanzibar by Bell (1903); and for Saya de Malha and Seychelles Is. by Bell (1909). None of this material was examined. We found no evidence of A. cepheus in the western Indian Ocean. The live colour of A. cepheus is sometimes uniform, frequently mottled, and varies greatly.