''Crowsoniella'' is a genus of

beetle Beetles are insects that form the Taxonomic rank, order Coleoptera (), in the superorder Holometabola. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 40 ...

s in the order

Archostemata The Archostemata are the smallest suborder of beetles, consisting of 50 living species in five families and over 200 described fossil species. They are an ancient lineage with a number of primitive characteristics. Antenna (biology), Antennae may ...

. It contains only a single species, ''Crowsoniella relicta'', and is the only member of the

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

family Crowsoniellidae. It is known only from three male specimens collected in 1973 in the Lepini mountains of central Italy by Roberto Pace. In a degraded pasture, the beetles were found among the roots of a large hawthorn tree, in deep

calcareous Calcareous () is an adjective meaning "mostly or partly composed of calcium carbonate", in other words, containing lime (mineral), lime or being chalky. The term is used in a wide variety of Science, scientific disciplines. In zoology ''Calcare ...

soil. No other specimens have been found since. At only in length, this species is comparatively small for this suborder. They also feature several unusual morphological features such as missing alae, modified and reduced mouth parts, and smooth

elytra An elytron (; ; : elytra, ) is a modified, hardened forewing of beetles (Coleoptera), though a few of the true bugs (Hemiptera) such as the family Schizopteridae are extremely similar; in true bugs, the forewings are called hemelytra (sometime ...

(lacking window punctures characteristic of this suborder). Nothing is known about this species' biology. Some authors have proposed a close relationship to Micromalthidae.

References

Archostemata Monotypic Archostemata genera Endemic arthropods of Italy Beetles of Europe {{Archostemata-stub