Pleistocene-speciation
Guides
Mycotrupes
Mycotrupes is a genus of flightless, earth-boring scarab beetles comprising five described species endemic to the southeastern United States. All species are allopatric, each restricted to isolated deep sand ridges in peninsular Florida or elevated sand hill habitats along the Piedmont-Atlantic Coastal Plain juncture in southern South Carolina and Georgia. The genus originated near the Fall Line during the Tertiary, with Pleistocene sea level changes driving subsequent speciation. Flightlessness evolved early through metathoracic wing degradation and median fusion of prothoracic elytrae.
Trogloderus
Trogloderus is a genus of psammophilic darkling beetles (Coleoptera: Tenebrionidae) endemic to dunes and sandy habitats in the western United States. The genus comprises ten described species, including six new species described in 2019 from desert regions across the Intermountain Region. Molecular phylogenetic analysis dates the most recent common ancestor to 5.2 million years ago, with speciation driven by geographic features of the Lahontan Trough, Bouse Embayment, and Kaibab Plateau during the mid-Pleistocene.
Trogloderus skillmani
Trogloderus skillmani is a newly described species of psammophilic darkling beetle (Tenebrionidae: Amphidorini) from the eastern Great Basin and Mohave Desert regions of the western United States. Described in 2019 by Johnston as part of a comprehensive phylogenetic revision of the genus, it is one of six new species recognized in a genus previously considered monotypic. The species is restricted to dunes and sandy desert habitats. Molecular phylogenetic analysis dates the most recent common ancestor of Trogloderus to approximately 5.2 million years ago, with current species having diversified during the mid-Pleistocene driven by geographic features of the Intermountain Region.