Pliocene
Guides
Alaocybites
A genus of small, eyeless or microphthalmic weevils in the family Raymondionymidae. Originally described from California with two eyeless species, the genus was later discovered in the Russian Far East (Primorsky Kray) and represented by a fossil in Alaska. The genus is characterized by reduced or absent eyes and the absence of tarsomere IV on all legs, traits associated with edaphic (soil-dwelling) habits.
Arenivaga floridensis
Florida Sand Cockroach
Arenivaga floridensis is a sexually dimorphic, fossorial sand cockroach endemic to Florida scrub ecosystems. It is the most geographically widespread faunal endemic of Florida scrub, documented from 11 peninsular sand ridges. Genetic analysis reveals three major mitochondrial lineages whose divergence corresponds with late Pliocene peninsula insularization, supporting a western origin hypothesis with colonization during the Pliocene or earlier. The species exhibits extreme sexual dimorphism: males possess fully developed wings and engage in low, erratic flight at dusk, while females are completely wingless and remain entirely fossorial throughout life. Its distribution is restricted to friable, sandy soils beneath light leaf litter of sand live oaks (Quercus geminata).
Callidium
Callidium is a genus of longhorn beetles (Cerambycidae) comprising approximately 24 described species distributed across North America and Eurasia. Species are associated with coniferous trees, particularly pines and spruces, where larvae develop in dead or dying wood. The genus has a fossil record extending from the Eocene to the Pliocene in Europe.
Olophrum boreale
Olophrum boreale is a rove beetle (Staphylinidae: Omaliinae) with a Holarctic distribution spanning northern Europe, Russia, and North America. The species occurs in boreal and montane habitats. Limited observational records suggest it is not frequently encountered.