Epikarst
Guides
Horologion
Horologion is one of the rarest and most enigmatic carabid beetle genera, containing two known species of troglomorphic ground beetles endemic to the middle Appalachian Mountains. The genus remained monotypic for over 60 years after its description in 1932, with a second species discovered in Virginia in 1991 and described in 2024. Phylogenetic analysis places Horologion in supertribe Trechitae as sister to the Gondwanan tribe Bembidarenini, making tribe Horologionini a relict lineage with no close relatives in the Northern Hemisphere.
Horologion hubbardi
Horologion hubbardi is a newly described species of carabid beetle from Bath County, Virginia. It represents only the second known species in the genus Horologion, which was previously known solely from a single holotype collected in West Virginia in 1931. DNA sequence data and morphological analysis place the genus in the supertribe Trechitae, as sister to the Gondwanan tribe Bembidarenini. The species is considered a relict lineage with no close relatives known in the Northern Hemisphere.
Horologionini
Horologionini is a relict tribe of carabid beetles (Coleoptera: Carabidae: Trechinae) containing the enigmatic genus Horologion. The tribe was newly recognized in 2024 based on DNA sequence data and morphological analysis. Phylogenetic analysis places Horologionini in the supertribe Trechitae as sister to the Gondwanan tribe Bembidarenini, rejecting previous hypotheses that placed the genus near Anillini, Tachyini, Trechini, Patrobini, or Psydrini. The tribe has no close relatives in the Northern Hemisphere and represents an important component of Appalachian biodiversity.