Type species: Hylaeus thoracicus Fabricius, 1793 by original designation.
Paramyrmosa Suárez, 1963, nom. praeocc., nec Saussure 1880, syn. Krombein 1976 With the description of Krombeinella brothersi sp. nov., nineteen species are now known in this genus. Each of the previously recognized species occurs in Palaearctic, mainly in the Mediterranean (Suárez & Nonveiller 1988, Lelej 2002). The genus is newly recorded from the Oriental region. A key to the known males is presented below.