Gryphus Megerle von Mühlfeld, 1811

Hansen, Jesper, 2024, Brachiopods of the Norwegian fauna northern North Atlantic and Arctic, with a focus on, Fauna norvegica 43, pp. 12-68 : 28

Genus Gryphus Megerle von Mühlfeld, 1811

Description: Shell moderately to strongly inflated ventribiconvex. Outline elongate egg-shaped to subpentagonal. Rectimarginate to broadly uniplicate anterior commissure; shiny and smooth without ornamentation. Shell matrix densely endopunctate, greatly thickened and heavy posteriorly. Colour white to light grey or yellowish. Ventral umbo short and curled greatly towards dorsal valve. Deltidial plates unite and partly fuse together, forming a symphytium and confining an egg-shaped, variably-sized foramen. Pedicle collar thick. Hinge teeth without dental plates. Vascula media of mantle canal system strongly impressed on valve floor and usually visible on valve exterior as two straight, diverging, whitish lines on both dorsal and ventral valves. Cardinal process small and transverse. Short, poorly developed dorsal median ridge reaching slightly anterior of 1/3 valve length and forked at the very front (usually visible through the shell). Short brachial loop about 1/4 valve length. Dorsal muscle scars reaching to about 1/5–2/7 valve length. Maximum length 40 mm.

Depth range: 73–2663 m depth ( Jeffreys 1878; Dall 1920).

Temperature range: 4.6–13.6˚C ( Jeffreys 1878; Allmen et al. 2010).