Members of the Dicyrtomidae are characterised by having a very short fourth antennal segment. Dicyrtoma fusca is the only UK species in this genus (c.f. Dicyrtomina - minuta, ornata, saundersi).
Dicyrtoma fusca is a small globular springtail (1-2mm) which varies considerably in colour from a dark maroon red to a paler yellow form, the mottled patterning also varies:
These forms are known as Dicyrtoma fusca var.1. There is also a much rarer melanistic dark (almost black) form, Dicyrtoma fusca var.2 (not known from VC55), and a leucistic form with dark ocelli on a pale eyepatch, Dicyrtoma fusca var. rufescens: