Leiopterella

Leiopterella is a genus of prehistoric eurypterid of the family Rhenopteridae. It contains one species, "Leiopterella tetliei", from the Early Devonian of Nunavut, Canada. The name is said to be derived from the Greek "leios" (meaning "smooth") and "pteros" (meaning "wing", a suffix traditionally applied to many eurypterid genera). The proper word for wing in ancient Greek is however "pteron" (πτερόν). The species name honors Dr. O. Erik Tetlie for his contributions to the study of fossil eurypterids. 
Description.
"Leiopterella" is defined as a rhenopterid with a turbinate carapace lacking a cuticular sculpture. The ventral sutures resemble those of "Eurypterus" and the gnathobases are large and robust. The genus possesses a short type-B genital appendage with a bi-lobed termination.
The holotype (and only published) specimen, CMN 53573, measures 37 mm long and 29 mm wide and consists of the prosoma, four opisthosomal segments, a faintly preserved metasoma, portions of the prosomal appendages and the genital appendage.
Classification.
"Leiopterella" is classified as a rhenopterid closely related to "Rhenopterus" and more derived than basal rhenopterids such as "Brachyopterus" and "Brachyopterella".