Middle Ordovician – Late Ordovician
Pseudolingula is an extinct genus of facultatively mobile infaunal suspension feeders
Identification in Hand Sample:
- Shell broad and subrectangular with concentric growth lines, phosphatic
- Ventral pseudointerarea with narrow, deep pedicle groove
- Oblique muscle scars placed on broadly divergent ridges
- Dorsal central and anterior lateral muscle scars placed close together
Pseudolingula sp. from the Arnheim formation of Mt. Orab, Ohio (OUIP 1179)
- Shell broad and subrectangular, with concentric growth lines. Umbonal muscle divided into pair of scars.
Treatise on Invertebrate Paleontology, Part H (2) (2000):
- Shell elongate to subrectangular; ventral pseudointerarea with narrow, deep pedicle groove; ventral visceral area extending anteriorly beyond midvalve; oblique muscle scars placed on broadly divergent ridges; dorsal visceral area bisected by broad median septum, extending from beak to anterior lateral muscle scars; dorsal central and anterior lateral muscle scars placed close together; vascula lateralia of both valves short, submedian, slightly converging; vascula media absent; inner surface of both valves with conspicuous wrinkling directly lateral to vascula lateralia.
- Inarticulate brachiopod. Note triangular outline, white, phosphatic shell material, and concentric growth lines. Genus found throughout the Cincinnatian.
Fossils of Ohio (1996):
- A small to medium sized lingulid brachiopod that has an elongate outline. The anterior margin of the outline may be flat or truncated. The phosphatic shell may be white. Concentric growth lines may be well preserved. This genus is recorded from the entire Cincinnatian Series.
Popov, Blodgett and Anderson (1994):
- Characterized by paired umbonal muscles, submedial, parallel, or slightly convergent vascula lateralia on both valves, and completely reduced vascula media.