Henricia uluudax Clark & Jewett, 2010, sp. nov.
Creators: name: Clark, Roger N.
name: Jewett, Stephen C.
Publisher: name: Zenodo
Year: 2010
Subjects: Biodiversity
Taxonomy
Animalia
Echinodermata
Asteroidea
Spinulosida
Echinasteridae
Henricia
Henricia uluudax

description: Henricia uluudax sp. nov.
Figures 21–26
Henricia spiculifera (Clark) Verrill, 1914: 232 (pars), non Cribrella spiculifera H.L. Clark, 1901.
Henricia leviuscula multispina Fisher, 1911: 286 (pars), non Henricia leviuscula multispina Fisher, 1910: 571.
Type locality: Alaska, Aleutian Islands, Fox Islands, Unalaska Island, NW entrance to Unalaska Bay, inside Eider Point (53º57. 33 N, 166º 35.5 W), 5 m.
Type material: Holotype, LACM 1999-178.001 (leg. R.N. Clark, 9 May, 1999); 1 Paratype, USNM 1125119 (leg. R.N. Clark, 9 may, 1999); 1, CASIZ 180536 (leg. R.N. Clark, 1999).
Material examined: 2, LACM 1997-219.001, Atka Island, Crescent Bay, point at W end, 10 m (leg. R.N. Clark & Robert Lauth, 8 July, 1997); 2, RNC, Unalaska Island, Eider Point, 0–5 m (leg. R.N. Clark, 2 October, 2001); 1, RNC, Seguam Island, 12 m (leg. Shawn Harper, 18 July, 2007); 2, LACM 2008-029.001, Avatanak Island, 6 m (leg. R.N. Clark, 12 June, 2008).
Diagnosis: Relatively small, fairly rigid, R to 5.3 cm (Holotype R = 4.5 cm), r to 10 cm, R:r 5–5.3; disc small, rays moderately long, slender, tapering. Abactinal plates small, close-set; some plates may form a single fine, faint medial line or ridge on the rays. Adambulacral plates with 19–24 fairly stout, compressed spines.
Description: Relatively small, R to 5.3 cm, r to 1.0 cm, R:r 5–5.3; disc small, rays moderately long, slender, tapering to fairly blunt tips (Figs. 21 & 22). Abactinal plates very small, close-set (Fig. 23); pseudopaxillae round on disc, becoming triangular on rays, forming a tight reticulation, some apical plates often very close-set, nearly coalescing, forming a single very fine line or ridge at apex of ray; plates crowned with 37–60 fine, divergent, thorn-tipped spinules, about 0.25 to 0.30 mm in length; usually 3 slender thorns per spinule; papular areas rather small, with 2 –3 papulae; madreporite small, circular, irregularly radially spinose, located about 1/3 of the distance between the anus and the edge of the disc. Superomarginals 2 or 3 times as large as abactinal plates; inferomarginals about 1/3 third larger than superomarginals, and bearing 60–70 thorny spinules; first intermarginal series about 1/2 as large as inferomarginals at base of rays, grading smaller aborally, extending about 40–50% of R, second series ends just pass the base of the rays; actinal interradial series extending 75–80% of R. Adambulacrals (Fig. 24) with a single deep furrow spine, and 19–24 actinal spines, one (or two) large, thick, blunt spines at edge of furrow, backed by 2–3 similar spines, followed by a group of 16–20 smaller spines behind (usually arranged in 3 rows). Oral plates (Fig. 25) with 3–4 thick, blunt marginal spines, and 6–9 similar, sub-oral spines; in addition there are two to four thick, blunt, triangular, teeth deep in the furrow near the distal edge of the plate. Color in life (Fig. 26) uniformly bright red.
Distribution: Found from Fox Islands, Avatanak Island (54º 05.188 N, 165º 22.839 W) (leg. R.N. Clark, 12 June, 2008) to Andreanof Islands, Atka Island, Crescent Bay, point at W end (leg. R.N. Clark & Robert Lauth, 8 July, 1997) at depths of 0– 12 m. Henricia uluudax appears to be an endemic Aleutian species.
Habitat: Intertidal and shallow subtidal, on cobbles and boulders encrusted with coralline red algae. Frequently in kelp beds [Eualaria (Alaria) fistulosa and Nereocystis luetkeana].
Etymology: The name is the Aleut native word for red; (pronounced ō lō thux).
Remarks: Henricia uluudax is very similar superficially to H. lineata, but may be distinguished by 1) the lack light colored lines of coalescing plates; 2) more numerous abactinal spinules, 37–60, compared to 18–41; 3) more numerous inferomarginal spines, 60–70, opposed to 28–36; and 4) more numerous adambulacral spines, 19–24 compared to 15–17. The spinose nature of this form led Fisher (1911) to consider this an "extreme variant" of H. multispinosa, and Verrill thought it to be (at least in part) H.L. Clark's Cribrella spiculifera.
It differs from the similar appearing H. vermilion by 1) the slender body; 2) differently shaped abactinal plates; 3) much more slender, divergent pseudopaxillar spinules, which bear (usually) just 3 long thorns, those of H. vermilion are pointed and bear numerous thorns, 4) the much more numerous adambulacral spines, 19– 24 as opposed to 7–10 in H. vermilion; and 5) presence of extensive intemarginal series.
From the southern H. leviuscula, it differs in having slender, divergent, 3-pronged abactinal spinules, and an intermarginal series extending to about 50% of R, H. leviuscula lacks an intermarginal series. True H. leviuscula is not known to occur north of extreme southeastern Alaska (Doug Eernisse, pers. comm., March, 2009). This species is part of a complex of several very similar appearing Henricia in the Aleutians.
description: Published as part of Clark, Roger N. & Jewett, Stephen C., 2010, A new genus and thirteen new species of sea stars (Asteroidea: Echinasteridae) from the Aleutian Island Archipelago, pp. 1-36 in Zootaxa 2571 on pages 12-14, DOI: 10.5281/zenodo.294234