Biology
Longitarsus nigerrimus
The sexes look very similar from above, but the females are generally slightly larger than the males.
They are small beetles - only 1.5--2mm long from the front of the head to the end of the wing cases.
Like most other leaf beetles, the new generation of adults emerge in late summer and feed up prior to overwintering in thick moss or in tussocky vegetation.
They emerge in midsummer, mate, lay eggs, and then die.
The larvae only take a few weeks to develop before pupating. The new adults emerge a short while later.
In southern England, both adults and larvae feed on the stems and leaves of the lesser bladderwort, Utricularia minor L., and possibly on other Utricularia species.