Tomocerus vulgaris (as its specific name would suggest) is a common and widespread species (although it is not the most common Tomocerus in Britain and Ireland and has only been recorded once from the SW). The spines on the inner side of the dens are simple and there are no large leaf-shaped scales close to the point where the dentes join the manubrium (Fig. 1 and 2). The empodial appendage of the foot is just over half as long as the claw (Fig. 3). The mucro is long and generally distinctive, with 4-9 medial teeth (Fig. 4).
However there have been a few records in the South-east of England of a Tomocerus that resembles Tomocerus vulgaris except that the mucro has only 1-2 medial teeth. These key to Tomocerina minuta (but certainly are not), or using Gisin (1960) they key to the spanish endemic Tomocerus catalanus. Their COI barcode was 94.3% identical to Tomocerus vulgaris, so these are probably just an unusual Tomocerus vulgaris. This odd form of Tomocerus vulgaris also had a red "upper lip" (fig. 6), and should be watched out for.