Chaetasterina Hess, 1970

Gale, Andrew S., 2020, The fossil record of the asteroid (Echinodermata) family Chaetasteridae Sladen 1889 and subfamily Hyalothricinae Fisher, 1911, Zootaxa 4858 (1), pp. 144-150 : 148

Genus Chaetasterina Hess, 1970

Diagnosis. Hyalothricinae in which the arms are short and strap-like and the abactinals are arranged in poorly defined transverse rows.

Type species. C. gracilis Hess, 1970 .

Remarks. The genus is referred to the Hyalothricinae on the following evidence;

- presence of tufts of glassy spines on the primary external ossicles.

- the small, tessellate abactinals which possess imbricating basal flanges

- the small inferomarginals, equal in size to the adambulacrals

The ossicle arrangement and morphology is quite different to that of the Chaetasteridae ( Fig. 1 C–F) in which the abactinals form longitudinal columns of blocky ossicles.

Figures

FIGURE 1. A, B, Arthraster dixoni Forbes, 1848. Holotype specimen NHMUK 47000, “Lower Chalk”, probably Middle Turonian, Balcombe, Sussex, UK.A, actinal surface, B, enlargement of abactinal surface and base of arms. C–F, Chaetaster longipes (Bruzelius, 1805). C, enlargement of actinal arm. D, enlargement of abactinal disc. E, actinal view of specimen. F, abactinal view of specimen. Recent, Mediterranean.