Xenylla xavieri is a scarce bluish species which reaches 0.8 mm in length. Records are from dry sites such as exposed moss on boulders although there are too few localities to know whether or not this is characteristic. The mucro is fused with the dens (Fig. 1) and does not bear the small lamella seen in Xenylla grisea. Another useful character is the presence of only 2+2 teeth on the tenaculum of Xenylla xavieri (Fig. 2) which have been observed in the four specimens in the NHML collection (other Xenylla have 3+3 teeth).