ammonites
Pseudozygopleura assertonsoris Knight 1930 (snail)

Gastropoda - Prosobranchia - Pseudozygopleuridae

Alternative combinations: Palaeostylus (Pseudozygopleura) assertonsoris, Pseudozygopleura (Pseudozygopleura) assertonsoris

Full reference: J. B. Knight. 1930. The gastropods of the St. Louis, Missouri, Pennsylvanian outlier: the Pseudozygopleurinae. Journal of Paleontology Memoir 4(4):1-88

Belongs to Pseudozygopleura according to P. J. Wagner 2011

Sister taxa: Palaeostylus (Pseudozygopleura) belli, Palaeostylus (Pseudozygopleura) eucharis, Palaeostylus (Pseudozygopleura) terebrus, Pseudozygopleura (Hemizygoides), Pseudozygopleura (Pseudozygopleura), Pseudozygopleura acuminata, Pseudozygopleura angustata, Pseudozygopleura baltea, Pseudozygopleura cirritus, Pseudozygopleura condrai, Pseudozygopleura contractus, Pseudozygopleura croneisi, Pseudozygopleura deloi, Pseudozygopleura eximia, Pseudozygopleura funis, Pseudozygopleura girtyi, Pseudozygopleura gracilis, Pseudozygopleura gradatus, Pseudozygopleura irrugata, Pseudozygopleura kellettae, Pseudozygopleura knighti, Pseudozygopleura lanceolatus, Pseudozygopleura lefebvrei, Pseudozygopleura limus, Pseudozygopleura macra, Pseudozygopleura micra, Pseudozygopleura moorei, Pseudozygopleura mucronatus, Pseudozygopleura multicostata, Pseudozygopleura palus, Pseudozygopleura pandus, Pseudozygopleura perversa, Pseudozygopleura plummeri, Pseudozygopleura pluricostata, Pseudozygopleura pugonis, Pseudozygopleura pulchra, Pseudozygopleura pupa, Pseudozygopleura rectus, Pseudozygopleura restis, Pseudozygopleura schucherti, Pseudozygopleura scitula, Pseudozygopleura scruposus, Pseudozygopleura semicostata, Pseudozygopleura sinuosior, Pseudozygopleura subulatus, Pseudozygopleura tenuivirga, Pseudozygopleura variegata, Pseudozygopleura yandellana, Pseudozygopleura (Pyrgozyga) warthini

Type specimen: YPM 12978, a shell. Its type locality is SL-1. Headwaters of Feefee Creek, north of Olive St. & west of Lindberg Blvd., 1.5 km northwest of Stratmann (Olivette), which is in a Moscovian marine shale in the Appanoose Formation of Missouri.

Ecology: epifaunal

Average measurements (in mm): shell 4.80 x 1.36