Aquilonastra richmondi, O, 2006

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 : 279-281

Aquilonastra richmondi sp. nov.

Figures 1, 4e, 6f,g, 10a

Asterina burtoni .— Jangoux, 1973: 35–38, fig. 13 (probably part, Mozambique material; non Asterina burtonii Gray, 1840 ).

Asterina burtonii .— Walenkamp, 1990: 67–72, figs 30, 31 (part, Mozambique material; non Asterina burtonii Gray, 1840 ).

Asterina coronata .— Jangoux, 1973: 38–39 (part, 3 Mozambique specimens; non Asterina coronata Martens, 1866 according to Walenkamp, 1990; non Asterina burtonii Gray, 1840 ).

ʻAsterinaʼ sp. 1. — Rowe and Richmond, 2004: 3287 (part, Grand Paté specimen), fig. 4 (colour).

Material examined. Holotype. Tanzania, Ras Kimbiji, lower littoral, under boulders, M. Richmond, 4 Sep 2004, NHM 2005.37 (alcohol).

Paratypes. Type locality and date, NHM 2005.35 (1) ; NHM 2005.36 (1).

Other material. Côtes dʼArabie, St. XLVII, 1901–1904, MNHN EcAs 11043 (1); Kenya, Kiunga Marine Reserve , 8 m, Apr 1999, MRAC 1739 (1) ; Zanzibar, Rousseau, 1841, EcAh 3884 (1); Tanzania, Mnazi Bay , Ruvula Peninsula , rocky, lower littoral, 3 Feb 2004, NHM 2004.2832 (1) ; Mombassa , NHM 1972.8.22.3–17 (2 of 14 seen); Comoros, Mayotte, Mission Cherbonnier 25, littoral reef, 1959, MNHN EcAs 11862 (1); Mission Cherbonnier 27, 1959, EcAs 11863 (1); NW Madagascar, Nossi-Bi I. (Nosy Bé), Plante Collection , 1965– 1970, EcAs 11865 (2); littoral reef, 2 Dec 1959, EcAs 11858 (5); Cherbonnier , 6 Oct 1959, EcAs 11859 (7); SW Madagascar, Mission Cherbonnier 201, Station Platier ,1962, EcAs 11861 (2); NE Madagascar, Ile Sainte Marie , Ile aux Nattes , 26 Jun 1960, EcAs 11860 (1); SE Madagascar, Fort Dauphin , Mission Decary , 1932, EcAs 11864 (1); Madagascar, Gruvel Collection , 1923, EcAs 10379 (1); Mauritius, Rodrigues I., Grand Paté , on coral, 20 m, 23 Sep 2001, AM J24287 (1) ; E South Africa, Sodwana Bay , 11 m, 10 Feb 2001, MRAC 1737 (1) ; 14 m, Aug 1999, MRAC 1738 (1).

Diagnosis. Non-fissiparous Aquilonastra species; rays 5, rarely 6, broad to narrow basally, tapered, narrowly rounded distally; up to R = 25 mm, r = 12 mm; form frequently asymmetrical, one ray shorter than other 4; gonopores abactinal; pedicellariae sometimes evident on upper rays and in interradii, 2–3 short, thick valves not significantly differentiated from adjacent spinelets.

At R = 20, r = 10 mm, abactinal plates closely imbricate, proximal edge projecting, spinelets subpaxilliform; 0–5 proximal doubly-papulate carinal plates; few proximal secondary plates, 0–2 per space; predominantly single large papula per space, sometimes 2; spinelets short, conical, bluntly pointed, subsacciform, not splay-pointed, frequently of two forms, thin on outer margin of plates, thick short on apex of plates (columnar to subgranuliform); up to about 20 spinelets on each proximal abactinal plate, predominantly over surface of plate, some in clusters of 3–4; distal interradial plates with up to about 8 long, thin, pointed spinelets, frequently splayed in distinctive widely radiating cluster per plate, overlapping spinelets of adjacent plates on larger specimens; superomarginal plates smaller than inferomarginals, superomarginal plates with up to about 7 spinelets per plate, inferomarginals with up to about 14 spinelets per plate, thin proximally thick distally.

Spines per actinal plate up to: oral 8, suboral 4, furrow 7, subambulacral 5, actinal interradial 5, predominantly 2; interradial spines thick, rugose, bluntly conical, subsacciform.

Colour (live). Sharply mottled with green, maroon, pale brown, pink, white, black (photos by M. Richmond); variable and changeable, mottled with red, pink, orange, white, grey, blue (Walencamp, 1990; with colour photos).

Distribution. Côtes dʼArabie, E Africa, Kenya, Tanzania, Comoros, Madagascar, Mauritius, E South Africa; under boulders and in crevices in rocks and live coral; 0– 20 m.

Etymology. Named for Matt Richmond, with appreciation of his contribution of material from Tanzania and Rodrigues I.

Remarks. Two distinctive features of A. richmondi are: frequently two forms of spinelets on the abactinal plates, thicker apically; splayed overlapping spinelet clusters on the distal abactinal plates. The detailed description and colour photos of A. burtonii by Walenkamp (1990) indicate that the Mozambique Inhaca material was not A. burtonii and is conspecific with A. richmondi . Ludwig (1899) reported Asterina cepheus for Zanzibar. There is no evidence in this study of A. cepheus occurring in the western Indian Ocean, but the morphologically similar A. richmondi is reported here for Zanzibar.