Philobrya sublaevis Pelseneer 1903

• Main Authors: Urcola, Matias Ricardo, Zelaya, Diego Gabriel
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2024
• Subjects: Biodiversity; Taxonomy; Animalia; Mollusca; Bivalvia; Arcida; Philobryidae; Philobrya; Philobrya sublaevis; Antarc*; Antarctic; Antarctic Peninsula; Antarctica; Bellingshausen Sea
• Online Access: https://doi.org/10.5281/zenodo.10994141; http://treatment.plazi.org/id/A279878B7419D221F5EAE4C4FB30FD0A

Philobrya sublaevis Pelseneer, 1903 (Figure 17) Philobrya sublaevis Pelseneer, 1903: 25, 26, 42, 43, pl. 7, figs. 93‒95, pl. 8, figs. 96‒99; Nicol 1966 (in part): pl. 4, fig. 7 [not pl. 4, fig. 5 = P. limoides ]; M̧hlenhardt-Siegel 1989: 159, pl. 2, fig. 13 and pl. 5, fig. 13. Type locality: Bellingshausen Sea, 64°24.7’S 64°19.2’W, 165 m. Material examined : Neotype (here designated; MACN-In: 44476). Antarctic Peninsula: Bahía Paraíso, [64°51’S 62°54’W] (MACN-In 35081: 2 spec). South Shetland: 61°26’S 56°25’W, 350 m (MACN-In 35281: 1 spec). South Orkney: 60°58.89’S 43°26.71’W, 399 m (MLP-Ma 16134: 1 spec); 60°53’S 44°33’W, 218 m (MACN-In 44477: 1 spec). South Sandwich: 59°54.79’S 32°28.93’W, 518 m (MLP-Ma 16133: 5 spec, 2 v). Distribution: Antarctica, from Bellingshausen Sea (Pelseneer 1903; this study) to Antarctic Peninsula (Nicol 1966), South Shetland (M̧hlenhardt-Siegel 1989), South Orkney (this study), and South Sandwich (this study); 165‒ 550 m. Description: Shell medium-sized (maximum L = 9.0 mm), ovate, high ( H/L = 0.96 ± 0.02, n = 18), compressed ( W/H = 0.60 ± 0.05, n = 8), delicate; dorsal slope ill-defined. Umbo broad, almost at anterior end, rounded, only slightly outstanding from shell outline in smaller specimens, but projected in larger ones. Umbonal angle: 105‒ 120° (n = 8). Dorsal margin with the anterior portion long, straight, markedly obliquely forward and the posterior portion arched, forming a continuous curve with the posterior margin. Ventral margin short, sinuous all along the ontogeny. Prodissoconch D-shaped, with posterior end higher than anterior end, markedly convex ventrally, of 700‒ 780 µm Lp, separated from the dissoconch by a prominent rim. Antero-dorsal and postero-dorsal areas poorly differentiated, sculptured with commarginal folds. Central area sculptured with 50‒54 fine radial ribs. Some ribs extending all along; other (shorter) ribs appearing exclusively distally, radiating or intercalated to the previous ones. Dissoconch whitish, shiny. Sculpture cancellate, consisting ...