''Schistomerus'' is an extinct

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of predaceous diving beetle that is known from one species, ''Schistomerus californense'', which inhabited Lake Barstow during the middle Miocene. It is the most common beetle found in the concretions from the

Barstow Formation The Barstow Formation is a series of limestones, conglomerates, sandstones, siltstones and shales exposed in the Mojave Desert near Barstow in San Bernardino County, California.Dibblee, T.W., Jr. (1967). Areal Geology of the Western Mojave Dese ...

. The specimens are typically preserved in three dimensions. All ontogenetic stages of the beetle are present in the concretions. The larval stages of the beetle are most commonly represented, and the mature larvae range from 4.5 - 5.5 mm long.Palmer, A.R., 1957, Miocene arthropods from the Mojave Desert California: U.S. Geological Survey Professional Paper, v. 294-G, p. 237-280. Only 3 adults have been recovered. Due to the preservational conditions of the formation, a number of individuals were preserved with intact internal anatomy. The

tracheal The trachea (: tracheae or tracheas), also known as the windpipe, is a cartilaginous tube that connects the larynx to the bronchi of the lungs, allowing the passage of air, and so is present in almost all animals' lungs. The trachea extends from ...

system as well as parts of the organism's nervous system have been described.

References

Miocene insects of North America Miocene California Prehistoric insects of North America Monotypic prehistoric insect genera {{Paleo-insect-stub

See also

References