Plaesiomyidae

Classification
Phylum: Brachiopoda
Class: Rhynchonellata
Order: Orthida
Family: Plaesiomyidae
Cincinnatian Genera: Austinella, Plaesiomys, Retrorsirostra

Geologic Range
Early Ordovician – Late Ordovician

Common Paleoecology
Plaesiomyidae is an extinct genus of stationary epifaunal suspension feeders

Description of the Family

  • Costelalte orthoids with receding or subparallel dental plates
  • Ventral muscle scar subquadrate to bilobate, variable enclosure by elongate diductor scars of lanceolate to oval adductor track
  • Notothyrial platform supporting large cardinal process and divergent brachiophores
  • Saccate ventral mantle canal system with divergent vascula media
  • Dorsal system sporadically preserved

Published Descriptions

Treatise on Invertebrate Paleontology, Part H, Vol. 3 (2000):

  • Costelalte orthoids with receding or subparallel dental plates, ventral muscle scar subquadrate to bilobate, with variable enclosure by elongate diductor scars of lanceolate to oval adductor track; notothyrial platform supporting large cardinal process and divergent brachiophores; saccate ventral mantle canal system with divergent vascula media, dorsal system sporadically preserved, variable.

Austinella


Plaesiomys


Retrorsirostra