Leiopterella is a genus of prehistoric eurypterid of the family Rhenopteridae. It contains one species, Leiopterella tetliei, from the Early Devonian of Nunavut, Canada.[1] 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).[2] The species name honors Dr. O. Erik Tetlie for his contributions to the study of fossil eurypterids.[3]
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.
Historically, Leiopterella was classified as a rhenopterid closely related to Rhenopterus and more derived than basal rhenopterids such as Brachyopterus and Brachyopterella. However, a 2021 study concluded that Leiopterella was more basal than previously thought.[4]