Krombeinella Pate, 1947 (as subgenus of Myrmosa Latreille, 1796). Canad. Ent. 78(11): 197. Male, female.
Gender. Feminine.
Type species. Hylaeus thoracicus Fabricius, 1793 (male), by original designation.
Taxonomic history. Raised to generic status by Lelej, 1985b: 57. Valid generic name.
Sex association. The female of the type species was associated and identified (as Myrmosa dubia Costa, 1858: 7) by André, 1900: 110.
Distribution. Palaearctic.