Synonyms and other taxonomic changes
Mesocoelopodinae (Tricoryninae) is usually treated as a distinct subfamily, but arguments for its separation are rather weak.
Size
contains many small species; maximum size is about 4 mm.
Identification
Body short, often +/- ball-like, or moderately elongate, rarely cylindrical (genus Petalium only). Antennae usually with tree terminal segments enlarged and triangular, rarely rather parallel-sided, or branched. In two genera, the antennae are serrate, with the terminal segments unmodified (Mesocoelopus, Neosothes).
Antennae usually completely hidden in retraction, rarely last segments partly visible (genus Calymmaderus).
Legs retracted in grooves of the ventral surface, like in pill beetles (Byrrhidae).
Food
the group contains, besides wood-borers, many fungivores and species breeding in dry, non-woody plants.
Remarks
The most species-rich subfamily in North America.
