Goniodiscaster H.L. Clark 1909

Mah, Christopher L., 2018, New genera, species and occurrence records of Goniasteridae (Asteroidea; Echinodermata) from the Indian Ocean, Zootaxa 4539 (1), pp. 1-116 : 39

Goniodiscaster H.L. Clark 1909

H.L. Clark 1909: 110; Döderlein 1935: 74; A.M. Clark 1993: 300 (checklist); Gates & Rowe 1995: 99.

Diagnosis. Skeleton robust, Body stellate, marginal plates form distinct frame around edge ( Fig. 15A ). Abactinal plates abutted, covered by continuous granular cover ( Fig. 15B ). Interradial regions with paired abactinal plates forming distinct “fold” in each interradius ( Fig. 15B ). Spines and/or tubercles present or absent. Marginal and actinal surface covered by granular cover. Pedicellariae absent.

Comments. It is argued herein that Goniodiscaster shares more characters with the Goniasteridae , specifically the Anthenoidinae , such as Anthenoides , and similar genera such as Ogmaster, Stellaster and Stellasteropsis . Goniodiscaster shares the more flattened body form, but also the interradial paired plates present in the interradii, and the distinct “fold” created by their contact ( Fig. 15B ) which I argue are synapomorphies for this group. A full summary of this group is premature and beyond the scope of this treatment.

Goniodiscaster was originally assigned to the Goniasteridae by H.L. Clark (1909) and retained there by Fisher (1919) and Clark and Rowe (1971). Döderlein (1935) moved Goniodiscaster to the Oreasteridae , where it has remained in most contemporary summary treatments and checklists (e.g., Spencer & Wright 1966, A.M. Clark 1993, Gates & Rowe 1995).

Figures

FIGURE 15. Goniodiscaster aegis n. sp. Holotype, USNM E51097. R=4.7, r=1.9 cm. A. Abactinal surface. Scale bar=1.0 cm. B. Closeup of abactinal surface with white box around interradial paired plates and “fold”. Scale bar=0.3 cm. C. Interradius showing superomarginal and inferomarginal plates.Scale bar=0.5 cm. D. Actinal surface. Scale bar=1.0 cm. E. Closeup of furrow and adambulacral spines. Scale bar =0.3 cm.