Bugging You From San Juan Island

I found this very tiny (1mm) beetle on the rim of the pool outside yesterday (Dec. 8, 2023). In my investigational efforts to identify my specimen, I have concluded it should be one of the Minute Brown Scavenger Beetles in the family Latridiidae (pronounced la-trid-eye-i-dee). As to species, I think it is Cartodere bifasciata – based on the color pattern of elytra – black markings between 2nd and 5th stria in anteriour third and behind middle; lateral black spot in about middle. (Bugguide, 2014).

This particular species is an Australian native and likely introduced to North America via international shipping. Records show this species in Nova Scotia about 1989 (Majka et al 2009). Looking on iNaturalist for observational reports of this species, I see a few (about 15 or so) in the box I drew. You can see in the attached screenshot the general area where they are turning up in the Western US. Again, likely introduced via international shipping cargo.

Adults of beetles in this family are generally known to feed on the reproductive structures of fungi, plant and animal materials, and slime molds (Evans, 2021). They are found in association with wet or damp habitats in open or forested areas, especially in leaf litter, decomposing wood, on trees, herbaceous vegetation, and in bird, mammalian, or hymenopteran nests (Majka, 2009).

References and Further Reading

Bugguide 2014. Cartodere bifasciata. Iowa State University. https://bugguide.net/node/view/108526

Evans, A. V. 2021. Beetles of Western North America. Princeton University Press, N.J.

Majka CG, Langor D, Rücker WH. 2009. Latridiidae (Coleoptera) of Atlantic Canada: new records, keys to identification, new synonyms, distribution, and zoogeography. The Canadian Entomologist. 141(4):317-370. doi:10.4039/n09-050.