Mediaster cuspidatus ( Lamarck, 1816 ) Jangoux, 2021

Jangoux, Michel, 2021, The asteroid species of Lamarck (Echinodermata: Asteroidea), Zoosystema 43 (13), pp. 213-252 : 225

cuspidata Lamarck, 1816 , Asterias

( Fig. 10 )

Asterias cuspidata Lamarck, 1816: 553 .

Goniaster tessellatus – Clark 1993: 256.

CURRENT STATUS. — Asterias cuspidata is transferred here to the genus Mediaster Stimpson, 1857 as Mediaster cuspidatus ( Lamarck, 1816) n. comb.

MATERIAL EXAMINED. — South Seas • MNHN-IE-2014-3 ; holotype; Baudin expedition (1800-1804); Péron and Lesueur leg . • MHNH; Lesueur drawings collection; ref. 74022; Baudin expedition.

DISTRIBUTION. — South Seas. (Note that the related species Mediaster australiensis H. L. Clark, 1916 was found in Australia [Victoria, Bass Strait] and Tasmania.)

REMARKS

Both Lesueur’s drawings and the original holotype label attest that Lamarck’s Asterias cuspidata originates from the South Seas. Surprisingly A. cuspidata was considered a synonym of the Atlantic Asterias tessellata Lamarck, 1816 , which is more than unlikely both geographically and morphologically. Lamarck himself reported that A. cuspidata “differs from Asterias tessellata because its angles continue with long spikes resembling straight horns or rays [On l’en distingue par ses angles prolongés en longues pointes comme des cornes droites ou des rayons]”. In fact, the cuspidata-tessellata problem results from the confusion between Asterias cuspidata Lamarck and Goniaster cuspidatus Gray, 1840 the latter being indeed synonym of Lamarck’s Asterias tessellata .

From its overall morphological features, Asterias cuspidata belongs to the Goniasteridae , and its closest genus is Mediaster Stimpson, 1857 . Indeed A. cuspidata is clearly related to the Australian species Mediaster australiensis H. L. Clark, 1916 ( Clark 1916: 30-31, pl. 9), a species known from Bass Strait and around Tasmania. Some differences occur, however, such as the general appearance (the disc area of A. cuspidata is narrower giving it a more stellate form) or the occurrence in A. cuspidata of a row of enlarged carinal plates. Therefore, awaiting additional information of M. australiensis variability, it sounds better to keep the two species separate.

Figures

FIG. 10. — Asterias cuspidata Lamarck,1816: A, B, abactinal (A) and actinal (B) surfaces; C, profile view; D, interradial arc and ambulacral armament; E, holotype of the species (A-D, MHNH, Lesueur collection 74022, details, courtesy of MHNH; E, MNHN-IE-2014-3). Scale bar: E, 50 mm.