Astrotholus molginos Mah 2023

• Main Author: Mah, Christopher L.
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2023
• Subjects: Biodiversity; Taxonomy; Animalia; Echinodermata; Asteroidea; Valvatida; Asterinidae; Astrotholus; Astrotholus molginos; Antarc*; antarcticus; Scotia Sea
• Online Access: https://doi.org/10.5281/zenodo.8090108; http://treatment.plazi.org/id/03C387E86621FFF1FF68E2928409FA7A

Astrotholus molginos n. gen, n. sp. FIGURE 4A–F Etymology The species epithet molginos refers to the Greek “of hide or skin” alluding to the dermis which covers the body surface of this species. Diagnosis Stellate body with R/r=1.2–2.0, abactinal plates imbricate, irregular on disk but showing strongly linear, transverse series interradially (Fig. 4A, B, D). Body surface covered by thin dermal tissue (Fig. 4D, E). Abactinal plates with 1–9, usually 2–4 short glassine spinelets with most arranged on the convex side of the imbricate plates (Fig. 4D, E), in single series interradially but in clusters elsewhere. Furrow spines 3 to 6 (at R= 2.2 cm), webbed in weakly palmate to straight series. Subambulacral spines two or three in a cluster standing apart from furrow spines, at transverse to oblique angle (Fig. 4F). Comments Astrotholus molginos n. gen. n. sp. appears to be the most morphologically dissimilar relative to the other species within Astrotholus n. gen. This is attributed to the flattened plates, as well as the dermis present on the abactinal surface and the relatively simple spination rather than the granuliform spinelets present in Astrotholus antarcticus (Fisher, 1940). This species shares the greatest morphological affinity with Astrotholus infernalis n. gen. n. sp. Occurrence Scotia Sea, South Atlantic, 2886–3876 m. Description Body stellate, R/r=1.2–2.0, disk strongly arched and centrally rising up above surface on arms triangular, interradial arcs weakly curved (Fig. 4A, B). Lateral edge thin and flat. No specimens found larger than R= 2.2 cm. Body surface covered with thin dermal tissue layer (Fig. 4A, B, D, E). Abactinal plates flat and round in outline, imbricate (Fig. 4B, D). Each plate with short glassine spinelets 1–9, mostly 2–4 located on proximal (non-imbricate) convex end of plate. Remainder of plate bare lacking accessories. Spinelets in clusters on most plates but arranged single file on interradial disk plate surfaces. Plates largest on disk and radial regions along arms, smallest ...