Milteliphaster Alcock 1893

Mah, Christopher L., 2022, New Genera, Species and Occurrences of Deep-Sea Asteroidea (Valvatacea, Forcipulatacea, Echinodermata) collected from the North Pacific Ocean by the CAPSTONE Expedition, Zootaxa 5164 (1), pp. 1-75 : 56-57

Milteliphaster Alcock 1893

Alcock 1893: 91; Macan 1938: 391; Mah 2018: 63.

Diagnosis. Body stellate (R/r=2.6–3.6), arms strap-like, triangular, with strongly upturned arm curl.

interradial arcs straight to weakly curved. Abactinal surface covered by sharp, prominent spines, especially along carinal series. Abactinal plates without spines, polygonal to irregular in shape, relatively small with approximately 10–15 across arm base in holotype and specimen described herein, surface smooth, flat to concave. Papular pores between plates, distinct. Marginal plates bearing 1 to many spines with raised base, surface otherwise flat or weakly concave, smooth forming lateral-facing series. Actinal plates with elongate, prominent pointed to blunt spines of varying abundance. Paddle-shaped pedicellariae present. Furrow spines 6–10, narrow with blunt tips, forming straight to weakly curved series.

Comments. Milteliphaster is part of the Calliaster “group”, a cluster of similar Goniasteridae , outlined by Aziz & Jangoux (1985) and Mah (2005, 2018) based on, but not limited to, the presence of prominent spines on the abactinal, marginal and actinal surfaces, as well as the transverse series of large subambulacral spines.

The name ‘ Milteliphaster’ has been historically misapplied to other “ Calliaster ”-like goniasterids with no clear basis. Calliaster regenerator , for example, was referred to Milteliphaster in Rowe & Gates (1995), a catalog with no figures or taxonomic argumentation showing the basis for the decision. Examination of the type material of the name-bearing species, Milteliphaster woodmason i Alcock 1893 led to restriction of the genus pending further understanding of Calliaster and boundaries of related genera. A re-description of this species has recently been performed ( Mah 2018).

Milteliphaster is differentiated from Calliaster on the basis of the shape and morphology of the abactinal and marginal plates. Superomarginal and inferomarginal plates in Milteliphaster are lateral-facing and displays a flat to weakly concave surface versus those in Calliaster which displays strongly convex surfaces. Abactinal plates show a parallel plate surface morphology with Milteliphaster displaying flat to weakly concave surfaces versus more convex surfaces in Calliaster . A manuscript detailing characters in Calliaster and related taxa is in preparation.