Ailsastra heteractis (H.L. Clark)

O'Loughlin, P. Mark & Rowe, Francis W. E., 2005, A new asterinid genus from the Indo-West Pacific region, including five new species (Echinodermata: Asteroidea: Asterinidae), Memoirs of Museum Victoria 62 (2), pp. 181-189 : 188

publication ID	https://doi.org/ 10.24199/j.mmv.2005.62.6
persistent identifier	https://treatment.plazi.org/id/03AE7635-470D-2037-FE88-61FBFA24FA52
treatment provided by	Felipe
scientific name	Ailsastra heteractis (H.L. Clark)
status

Treatment

Ailsastra heteractis (H.L. Clark) View in CoL

Figures 1 View Figure 1 , 2e View Figure 2 , 3e View Figure 3 , 5d–f View Figure 5

Asterina heteractis H.L. Clark, 1938: 152–153 View in CoL , pl. 22 fig. 5.—H.L. Clark, 1946: 130, 133.—Rowe (in Rowe and Gates), 1995: 34-35.

Aquilonastra heteractis View in CoL .— O’Loughlin and Waters, 2004: 11, 13, 15.

Material examined. Holotype (dry). Australia, Lord Howe I., Neds Beach, under rock fragment, littoral, K. Birmingham, Apr 1932, MCZ 3258 About MCZ .

Paratypes (dry). Lord Howe, Neds Beach, MCZ 3259 About MCZ (1) ; dredged from lagoon near Goat I., MCZ 3260 About MCZ (2).

Other material (dry). Queensland, Townsville, AM J9541 (2); reef flat, Heron I., AM J19449 (1).

Diagnosis. Ailsastra with 6–7 discrete high rays with narrow bases, R /r about 2.0; multiple inconspicuous madreporites; fissiparous habit; abactinal gonopores; spinelets up to 0.15 mm long; large proximal actinal interradial pores; up to 4 spines per actinal interradial plate.

Description. 6–7 rays, R up to 7 mm; integument evident; rays discrete, narrow base, long, blunt distally, high convex abactinally, R /r about 2.0; multiple inconspicuous madreporites; fissiparous, ray lengths frequently unequal; abactinal paired interradial proximal gonopores. Carinal series of plates broadly visible, slightly below adcarinal plates, doubly papulate for most of ray, not proximally, other ray plates slightly indented for single large papula, single longitudinal series of papulae on each upper side of rays, 4 longitudinal series across mid-ray; papular spaces large; disc not delineated; spinelets glassy, stout, conical to subsacciform, splay-pointed, up to about 8 per plate, in single or double series across plates or in apical tufts, up to 0.15 mm long; superomarginal plates with up to 4 spinelets; inferomarginal plates with up to 10 longer, splay-pointed webbed spinelets. Single large proximal actinal interradial pores. Actinal spines per plate: oral 4–6; suboral 0–3; furrow (proximal) 3–4; subambulacral 3–4; adradial actinal 2–4; interradial 1–3; interradial spines subsacciform, elongate, pointed.

Colour (live). Salmon pink to light orange to nearly white abactinally, whitish actinally (H.L. Clark, 1938).

Distribution. Lord Howe I., NE Australia, littoral to shallow sublittoral.

Remarks. The presence of large single proximal actinal pores is unique amongst the asterinids. There was inadequate material to confirm by dissection the nature of the pores. They were observed only on the holotype. The distal oral spines are close to the suboral spines on the characteristic small oral plates, and sometimes appear to be in continuous series. O’Loughlin and Waters (2004) assigned Asterina heteractis to Aquilonastra O’Loughlin, 2004 , but noted some exceptional characters. A. heteractis has the carinal plate arrangement and small oral plates of Ailsastra paulayi , the type species of Ailsastra , and is reassigned to this new genus. No specimen was dissected to confirm an absence of superambulacral and superactinal plates.