Astrotholus antarcticus CASIZ
Astrotholus antarcticus (Fisher, 1940) FIGURE 1A–F Anseropoda antarctica Fisher, 1940: 149; Madsen 1955: 13; A.M. Clark 1962: 32 (key only); Bernasconi 1973a: 344. Diagnosis Body stellate (R/r=1.4–1.7), disk thick, strongly arched. Interradial arcs weakly curved to straight (Fig. 1A). Abactinal plat...
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| Format: | Other/Unknown Material |
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Zenodo
2023
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| Online Access: | https://doi.org/10.5281/zenodo.8090090 http://treatment.plazi.org/id/03C387E86638FFE8FF68E6B285EFFE4E |
| Summary: | Astrotholus antarcticus (Fisher, 1940) FIGURE 1A–F Anseropoda antarctica Fisher, 1940: 149; Madsen 1955: 13; A.M. Clark 1962: 32 (key only); Bernasconi 1973a: 344. Diagnosis Body stellate (R/r=1.4–1.7), disk thick, strongly arched. Interradial arcs weakly curved to straight (Fig. 1A). Abactinal plates scalar, imbricate, covered by widely spaced truncate granuliform spinelets, 3 to 6, (Fig. 1B) distribution patterns associated with underlying plates. Superomarginals oval to quadrate with rounded edges in 1:1 relationship with inferomarginals. Superomarginals approximately twice to three times wider than inferomarginals, at least as viewed on the abactinal surface (Fig. 1C). Actinal plates with short, thorn-like spinelets, 2 to 5 (Fig. 1F). Furrow spines thorn-like, webbed 2 to 5 (6 indicated on the type) with spine number decreasing distally. Subambulacral spines, 2–5, webbed, arranged as an oblique comb relative to the furrow spines (Fig. 1D). Comments Except for a further occurrence of this species from the type locality (Madsen 1955), few accounts of this species have been reported since its original description (Fisher 1940). Species epithet has been changed to reflect change in genus name. Comment on Paratype USNM E10104 for Anseropoda antarctica Examination of USNM E10104, a paratype specimen for Anseropoda antarctica listed by Ahearn (1995) reveals that it is incorrectly identified and not part of the original type series as designated by Fisher (1940). The specimen displays the plate pattern and the continuous granulation that identifies Kampylaster incurvatus rather than Anseropoda antarctica . Fisher (1940) listed seven specimens as part of the original type series, all of which were confirmed in the Discovery collections at the British Museum of Natural History (J. Ablett, pers. comm.). Although Kampylaster incurvatus is reported in Fisher (1940), no specimens from the Clarence Island type locality were listed in his account bringing the locality data for USNM E10104 into doubt. Occurrence Bransfield ... |
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