Lepidocyrtus ruber is a pale species with traces of blue pigment on the head, thorax and legs, up to 1.4 mm in length. The second thoracic segment is not prominent and there are no scales on the legs or antennae. It should be easy to identify under the microscope as the empodium on the foot is highly characteristic with a sharply angled tip (Fig. 1). This is extremely obvious and should not be confused with any other species of Lepidocyrtus. Like all Lepidocyrtus, the mucro has two teeth and a spine (Fig. 2).
There are several widely scattered records which appear mostly to be from wet habitats (it has been suggested that the unusual shape of the empodium may be an adaptation for walking on water).
Mateos (2008) described Lepidocyrtus ruber as having scales on ant I-II and the legs, while Steve Hopkin's key says this species lacks scales there. It is likely that these are in fact two different species - indeed the whole genus Lepidocyrtus seems riven with cryptic species.
Mateos, E. 2008. The European Lepidocyrtus Bourlet, 1839 (Collembola: Entomobryidae)., Zootaxa 1769, 14 May 2008, p.35-59.