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Pseudarchaster portlandicus

Asteroidea - Valvatida - Goniasteridae

Archastropecten portlandicus was named by Hess (1955). It is not extant. Its type specimen is Holotype BNHM E 13739.

It was recombined as Pentasteria portlandica by Hess (1960); it was recombined as Pseudarchaster portlandicus by Blake (1986) and Villier (2010); it was recombined as Pentasteria (Pentasteria) portlandica by Roman et al. (1993); it was recombined as Pentasteria (Pentasteria) portlandicus by Lewis (1993); it was recombined as Pentasteria (Archastropecten) portlandicus by Gale (2011).

Synonymy list
YearName and author
1955Archastropecten portlandicus Hess pp. 53-54 figs. fig. 13-15, pl. 4, fig. 4-6
1960Pentasteria portlandica Hess p. 330
1986Pseudarchaster portlandicus Blake pp. 1111-1112 figs. fig. 2.1-5
1993Pentasteria (Pentasteria) portlandicus Lewis p. 63
1993Pentasteria (Pentasteria) portlandica Roman et al. p. 13 figs. pl. 2, fig. 1
2010Pseudarchaster portlandicus Villier
2011Pentasteria (Archastropecten) portlandicus Gale p. 57

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If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.

D. B. Blake 1986Arm outline elliptical, with very gradual rate of taper, stout marginal frame. Abactinals are paxillae with generally circular transverse sections; crown, column, base differentiated but some ossicles with proportionally low, ill-defined columns; diameter approximately 0.5 mm. Outer faces with polygonal granules, at least one central granule with surrounding ring of about 9. Marginals stout, paired, semicircular in outline with planar face, low articular ridges on side faces, ossicles of two series similar; intermarginal channels sharply defined but shallow; superomarginals with closely appressed polygonal granules, granules smaller near face margins, leaving shallow depressions on surfaces; inferomarginals with distal abradial row of about 4 flattened, pointed spinelets up to approximately 1.25 mm long, remainder of surface covered by similar but shorter spinelets; spinelet bases clearly defined. Actinals lacking from distal fragment. Adambulacrals elongate, stout, strongly overlapping next distal ossicle with angular furrow margin; small spine bases bearing longitudinal row of about 6 columnar, gradually tapered spinelets, all approximately 1.25 mm long; spinelets with blunt, rounded tips. Subambulacral surface longer than wide, with 2 irregular rows of spinelet bases; one or on some ossicles, two flat pointed spinelets approximately 1.25 mm long near distal end of ossicle, remainder of spinelets less than 0.5 mm long. Pedicellariae absent.
Ambulacrals stout, ambulacral bodies long, weakly overlapping, sub-symmetrical outline with prominent sub-vertical proximal ambulacral - ambulacral articular surfaces; dentition fine, supradental muscle depression semicircular, shallow; subdental muscle depression sharply defined. Abactinal ridge prominent, angular medially, rounded proximally; ambulacral - adambulacral muscle wings similar; ambulacral - adambulacral articular facets symmetrical, typically valvatidan.