Quasillites

Quasillites is a fossil genus of ostracod from the Devonian and Carboniferous Periods.^[1][2]

Quasillites Temporal range: Middle Devonian to Lower Carboniferous 388.1–342.8 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Ostracoda
Order:	Platycopida
Family:	†Quasillitidae
Genus:	†Quasillites Coryell & Malkin, 1936
Species
Quasillites angulatus Quasillites fromelennensis Quasillites lobatus (Schwartz & Oriel) Quasillites obliquus (Coryell & Malkin, 1936) Quasillites subobliquus

Description

Quasillites is distinguished from other ostracodes by the presence of a "medial spot" on each valve.^[2] The surface of each valve is covered in longitudinal, bifurcating ridges, which curve and resemble a finger print.^[2][3] The ribs and spines on the carapace are in front of the posterior margin, and are similar to those of other ostracods such as Bufina, Parabufina, and Healdia.^[4] In fact, this comparison can also be drawn for all Quasillitids to other Healdiids.^[4] The muscle scars on each valve is circular in shape, and some specimens have smaller secondary scars.^[4]

Distribution

Devonian examples of Quasillites, such as Q. lobatus, Q. obliquus, Q. subobliquus, and Q. angulatus, are known from shales and claystones in northern New York, Eastern Ohio, central Pennsylvania.^[2][3][5][6] Other species such as Q. fromelennensis and a second informal species can also be found in Limestones of northern France, near the city of Calais.^[7] This genus has also been found in the Lower Carboniferous edge of the Illinois Basin; in central Indiana.^[1]