Pseudonepanthia A. H. Clark 1916
Creators: name: O'Loughlin, P. Mark
name: Waters, Jonathan M.
Publisher: name: Zenodo
Year: 2004
Subjects: Biodiversity
Taxonomy
Animalia
Echinodermata
Asteroidea
Valvatida
Asterinidae
Pseudonepanthia

description: Pseudonepanthia A.H. Clark
Figures 1, 3c, 4e, 5d, 14d–f
Pseudonepanthia A.H. Clark, 1916: 118.—A.M. Clark, 1993: 227.
Diagnosis. Rays 4–10, subcylindrical, not flat actinally, lacking marginal edge; integument variably noticeable; lacking secondary plates; abactinal spinelets thick or thin or subsacciform, covering plates or in tufts; lacking pedicellariae; plates lacking glassy convexities; inferomarginal plates not projecting; furrow spines up to 5 per plate; actinal interradial spines digitiform, up to 7–30 per plate; series of superambulacral plates present, rare transactinal plates; lacking superactinal plates.
Type species. Pseudonepanthia gotoi A.H. Clark, 1916 (original designation).
Other species. P. briareus (Bell, 1894); P. gracilis (Rowe and Marsh, 1982); P. grangei (McKnight, 2001) (in Clark and McKnight); P. nigrobrunnea (Rowe and Marsh, 1982); P. reinga (McKnight, 2001) (in Clark and McKnight); P. troughtoni (Livingstone, 1934).
Material examined. P. briareus. Mariana Is, Guam, 118–152 m, UF 226 (1).
Pseudonepanthia gotoi. Holotype. Japan, Sagami Bay, 90 m, USNM 36899.
P. gracilis. Australia, New South Wales, AM J12874 (2); J11880 (2).
P. nigrobrunnea. New South Wales, Coffs Harbour, NMV F95810 (2); Byron Bay, F95804 (1).
Parasterina troughtoni. Holotype. Western Australia, Albany, AM J3978. Other material. Victoria, Cape Woolamai, NMV F73013 (1); Wilsons Promontory, F73017 (1); South Australia, Cape Jervis, F73977 (4).
Description with species variations. Rays 4–10, distinct, elongate, subcylindrical, tapered slightly (nigrobrunnea, troughtoni) or strongly (briareus, gotoi, gracilis, grangei, reinga), some irregular (briareus, gotoi, nigrobrunnea); integument variably noticeable; margin rounded, rays not flat actinally, lacking marginal edge; size large (troughtoni up to R = 87 mm) to medium (grangei up to R = 33 mm); lacking pedicellariae; gonopores sometimes actinal (troughtoni); one fissiparous (briareus).
Abactinal plates imbricating, projecting proximal edge creating uneven surface, irregular in form and arrangement on upper rays, oblique longitudinal series along sides of rays; lacking secondary plates; papulate areas extending to near margin; papular spaces with single large papula or a few (nigrobrunnea); abactinal plates with spinelet-bearing elevations or not (troughtoni); spinelets glassy, subsacciform with splayed points distally (briareus, gotoi), or subsacciform (gracilis), or fine columnar (nigrobrunnea, troughtoni); spinelets covering plates closely (gotoi, gracilis, nigrobrunnea, troughton i) or in splayed groups (briareus); disc not bordered; cleared plates lacking glassy convexities; superomarginal plates in regular or irregular series; marginal plates covered with abactinal type spinelets; inferomarginal plates in predominantly regular series, frequently longitudinally elongate, not projecting.
Actinal plates with spine-bearing elevations or not (troughtoni); not in oblique series.
Actinal spines per plate: oral 3–10; suboral 4–12; furrow 3–5; subambulacral 6–10; actinal 7–30; adradial row of actinal plates with complete series of spines; interradial actinal spines digitiform.
Superambulacral plates present as predominantly single series along ambulacrum, sometimes contiguous with inferomarginal plates across floor of ray (briareus, troughtoni) or with abactinal plates (nigrobrunnea); rare transactinal plates (sometimes irregularly present in gracilis); lacking superactinal plates; interior of rays with resinous lining.
Distribution. Mariana Is, SE Japan, South China Sea, Philippines, E Indonesia, E and S Australia, New Zealand; 0– 540 m.
Remarks. Molecular data are available for P. troughtoni only. This review is based on morphology. Six species are removed from Nepanthia to Pseudonepanthia which is distinguished by: rays not flat actinally, lacking a marginal edge; absence of secondary plates, pedicellariae and glassy convexities; furrow spines fewer than 6 per plate; absence of transactinal and superactinal plates.
McKnight (in Clark and McKnight, 2001) referred Nepanthia grangei and N. reinga “provisionally” to Nepanthia. Material has not been examined, and internal skeletal plates not observed. Based on the descriptions, the absence of secondary plates and pedicellariae, and presence of up to five furrow spines per plate, fit the diagnosis of Pseudonepanthia to which both species are reassigned.
description: Published as part of O'Loughlin, P. Mark & Waters, Jonathan M., 2004, A molecular and morphological revision of genera of Asterinidae (Echinodermata: Asteroidea), pp. 1-40 in Memoirs of Museum Victoria 61 (1) on pages 32-33, DOI: 10.24199/j.mmv.2004.61.1, http://zenodo.org/record/10665495