[4][6] Lepisosteus appears to have a wider distribution in the past, as the extinct species L. bemisi inhabited intermountain lakes in the Green River Formation of what is now Wyoming, significantly west of the genus's modern range.

[7] Even more removed from the genus's present distribution was L. indicus from the Maastrichtian-aged Lameta Formation and Intertrappean Beds of India.

This species' inclusion in Lepisosteus is uncertain, as it was classified based on characteristics of the skull that were later found to be shared among many different gar taxa.

[6] In comparison to their long snouts, Lepisosteus have relatively small heads; however, their mouths full of sharp teeth.

[6] Fish of this genus that are newly hatched will attach themselves vertically to submerged objects by an adhesive disc on their snout.

Because Lepisosteus has evolved to be a top predator, they are voracious eaters that eat a variety of other freshwater fish and crustaceans such as Ictiobus and blue crabs.

Adults will float toward the surface of streams to scout prey that are below them while younger fish in this genus will hide in submersed vegetation to ambush hunt.

[13] Studies have found this native North American species is a predator of invasive Asian carp, whose habitat they share.

[16] Phylogenetic evidence suggests that Lepisosteus is ancient genus that diverged from its only extant relative, Atractosteus, during the Early Cretaceous.