ursinus species group

This group is characterized by the presence of hooked hairs on the mouthparts of the females (Figs. 9A–B). Hooked hairs are present on the stipes, on the prementum and on the first two segments of the labial palpus, except in A. halictoides, which lacks such hairs on the second segment of the palpus. One species, A. bonariensis, also has modified hairs on the hypostomal area of the head, on the trochanters, and on the metasomal sterna (Fig. 9C). Species of the group are 6.2–11.0 mm long. Males have a ventral tubercle in front of the middle coxa, except A. bonariensis which lacks the tubercles. Yellowish hairs are usually present on the metasomal apical bands and/or on the tibial scopa of females (Fig. 1), and males of some species are entirely covered by golden pile ( A. ursinus, A. mesopotamica, A. duckei, and A. holmbergi), or nearly so ( A. bonariensis) (Fig. 2).