''Sinodendron rugosum'' is a species of the family

Lucanidae Stag beetles are a family of about 1,200 species of beetles in the family Lucanidae, currently classified in four subfamilies.Smith, A.B.T. (2006). A review of the family-group names for the superfamily Scarabaeoidea (Coleoptera) with corrections ...

, the stag beetles. It is commonly referred to as the rugose stag beetle, and is the only known member of the genus '' Sinodendron'' to occur in western

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

Description

The adults of this species exhibit

sexual dimorphism Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...

, a common trait in

, as well as unopposable clubbed antennae. Both sexes are in length, black in coloration, and have small mandibles. The pronotum and

elytra An elytron (; ; , ) 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 (sometimes alterna ...

are covered in many small pits, leading to an overall

rugose Rugose means "wrinkled". It may refer to: * Rugosa, an extinct order of coral, whose rugose shape earned it the name * Rugose, adjectival form of rugae Species with "rugose" in their names * '' Idiosoma nigrum'', more commonly, a black rugose tr ...

appearance. The head of the male is much narrower than the

pronotum The prothorax is the foremost of the three segments in the thorax of an insect, and bears the first pair of legs. Its principal sclerites (exoskeletal plates) are the pronotum (dorsal), the prosternum (ventral), and the propleuron (lateral) on ea ...

, and has a short, median

rhinoceros A rhinoceros (; ; ), commonly abbreviated to rhino, is a member of any of the five extant species (or numerous extinct species) of odd-toed ungulates in the family Rhinocerotidae. (It can also refer to a member of any of the extinct species o ...

-like horn. The female either lacks a horn or has a small median tubercle.

Range

''Sinodendron rugosum'' is found in moist woodlands from British Columbia to California. Adults are commonly found on the ground from spring to early summer.

Life history

The white, C-shaped larvae hatch on bark and tunnel inward, creating pupal chambers in decaying wood. They have been associated with oak, alder, willow and cherry. Adults may feed on plant juices or aphid honeydew. The horn of the male is occasionally used in combat with other males in order to establish dominance when competing for mates.

Predators

''Sinodendron rugosum'' has been identified as one of many species eaten by the Northern Spotted Owl '' Strix occidentalis''.

References

External links

{{Taxonbar, from=Q2577863 Syndesinae Beetles of North America Beetles described in 1843