Sekstantilla

Sekstantilla is a small leaf beetle belonging to the family Chrysomelidae. The species was first described in 1987 by Finnish entomologist Erkki Mäkelä based on specimens collected from the pine forests of the Kainuu region. Its scientific name, Sekstantilla lignosa, reflects the wood‑associated habitats where it is commonly found. The beetle measures roughly 4.5 to 5.0 millimetres in length and displays a mottled grayish‑brown exoskeleton with subtle iridescent patches along the elytra.

Morphologically, Sekstantilla is distinguished from congeners by the presence of a unique longitudinal groove on the dorsal surface of the pronotum and by the unusual pattern of setae on its antennae. The larvae feed primarily on needles of Scots pine (Pinus sylvestris) and are often observed under the bark during late summer. Adults are most active from May to July, during which they exhibit crepuscular flight patterns. Predators include small birds and ground‑dwelling predators such as ground beetles (Carabidae).

The species’ distribution is largely restricted to boreal forests of northeastern Finland, with occasional records in adjacent parts of Estonia. Climate change and changes in forest management practices have prompted some conservation concern. Recent surveys indicate a slight decline in local population density, although the species is not currently listed as threatened. Further research into its life cycle and habitat requirements is recommended to aid in monitoring efforts.