Middle Ordovician – Early Carboniferous
Pseudolinguilidae is an extinct family of facultatively mobile infaunal suspension feeders
Description of the Family
- Shell elongate, subrectangular to subelliptical.
- Ventral pseudointerarea with small, triangular propareas lacking flexure lines
- Dorsal posterior margin thickened
- Poorly developed or absent dorsal vascula media
- Umbonal muscle bisected by the pedicle nerve
Treatise on Invertebrate Paleontology, Part H (2) (2000):
- Shell elongate, subrectangular to elongate subelliptical, subequivalved to equivalved; ventral pseudointerarea with small, triangular propareas lacking flexure lines; dorsal posterior margin thickened, forming reduced, undivided, anacline to catacline pseudointerarea, never extending as plate into valve; both valves with paired umbonal muscle scars; ventral valve with impression of pedicle nerve bisecting umbonal scar; dorsal scars of central and anterior lateral muscles closely spaced; mantle canal system baculate or possibly bifurcate, vascula lateralia converging anteriorly; vascula media absent.
- The pseudolingulids are characterized by by the presence of of converging vascula lateralia, poorly developed or absent dorsal vascula media, and reduced pseudointerareas, in addition to a paired umbonal muscle, bisected by the pedicle nerve.