Everywhere I look I'm finding so many Bristly Ladybirds,
Rhyzobius lophanthae, overwintering in evergreens in Leicester this year.
Rhyzobius lophanthae is native to Australia. The current global distribution of
R. lophanthae is driven by biological control efforts. It was intentionally introduced into California in 1892 as an agent to manage scale insects. Since that initial release, it has successfully spread across much of the southern United States and Europe demonstrating its capacity for dispersal.
R. lophanthae is a recent addition to British Ladybirds, with the first documented record in London in 2008.
This
is one of the micro ladybirds, with adult length typically around 2 mm. Adults are oval when viewed dorsally and notably dome-shaped in profile. Key features for identification include the color contrast: the elytra (wing covers) are black or dark reddish-brown, often exhibiting a metallic bronze sheen, contrasting sharply with the dull orange or reddish-brown head, prothorax, legs, and underside. The entire dorsal surface is covered densely with short, pale hairs interspersed with longer, darker bristles, a trait that gives it the common name, Bristly Ladybird.
R. lophanthae tends to be concentrated in anthropogenic habitats. Records are primarily associated with parks, domestic gardens, and botanical gardens. These findings indicate a strong reliance on microclimates that offer more favorable temperature regimes than the surrounding rural landscape. A critical observation is the close association between the presence of the ladybird and ornamental conifers (Cupressaceae), confirming that the beetle’s habitat niche in the UK is intrinsically tied to the distribution of its specialized scale insect food source.
It seems that high temperature requirement for reproduction restricts the species to a maximum of one, or potentially two, generations per year (univoltine or partially bivoltine) in ambient UK conditions. Consequently, the establishment success of
R. lophanthae in the UK is less determined by the cold tolerance of overwintering adults and more fundamentally limited by the restricted temporal window available for reproduction. Thus the extreme weather of 2025 seems to have favoured this species.
So you know what you're looking for, here's one on a pencil for scale (yes, they're small). Dark brown abdomen, reddish head, all brown underside. Most characteristic are the bristles extending from the lighter fuzz on the elytra (close-up photos required).
