Halictillus Moure, 1947

ENGEL, MICHAEL S., 2000, Classification Of The Bee Tribe Augochlorini (Hymenoptera: Halictidae), Bulletin of the American Museum of Natural History 2000 (250), pp. 1-89 : 53

Genus Halictillus Moure

Halictillus Moure, 1947: 7 . Type species: Chloralictus loureiroi Moure, 1941 , monobasic and original designation.

DIAGNOSIS: Species of Halictillus are the most Halictini-like among all augochlorines and strongly resemble the genus Dialictus (in fact, more often than not, they are misidentified as species of Dialictus ). The strong distal wing venation, medioapical cleft in the female T5, the absence of a pygidial plate in males, and the presence of a spiculum on S 8 in males all attest to the placement of this group in Augochlorini . Species are minute dark, and dull metallic blue-green.

DESCRIPTION: Female. Mandible with moderate subapical tooth. Labral distal process narrowly triangular; basal elevation orbicular; lateral margins of distal process serrated. Prementum not greatly elongate. Galeal apex rounded; galeal comb present; galeal base extending about half of distance to stipital base. Hypostomal ridge carinate; anterior angle rounded. Malar space less than mandibular width. Epistomal sulcus obtuse Ocelli not greatly enlarged; ocellar furrow absent. Vertex not expanded or ridged behind ocelli. Preoccipital ridge rounded. Pronotal lateral angle not produced, obtuse; dorsal ridge carinate; lateral ridge rounded. Mesoscutal anterior border rounded; mesoscutal lip rounded. Tegula oval. Basitibial plate bordered posteriorly, margin obsolescent anteriorly. Inner hind tibial spur pectinate. Apex of marginal cell acute. Distal hamuli with irregular spacing pattern. Basal area of propodeum granular; propodeal pit set into notch. Male. Mandible simple. Labrum without distal process; basal area not notched Antennae long, extending beyond propodeum; F2 much longer than F1, usually longer than or as long as scape. Inner hind tibial spur serrate. Metasoma elongate. Apical margins of S4 and S5 unmodified. Apical margin of S6 not emarginate. Apical margin of S7 with median process. Apical margin of S8 with median process; spiculum broad. Proctiger unmodified. Gonobasal bridge broad dorsal lobes weak. Basal process of gonostylus and parapenial lobe absent; dorsal process reduced to a ridge bearing setae. Ventral surface of penis valve unmodified; dorsal bridge near apices.

REVISIONS: There has been no attempt to revise the species of Halictillus . At present only two species, H. glabrescens (Cockerell and H. loureiroi (Moure) , are included in the genus.

BIOLOGY: The biology of H. glabrescens was investigated by Claude-Joseph (1926 under the name Halictus glabriventris Friese ).

DISTRIBUTION: Halictillus occurs in northern Argentina, southern Brazil, and Chile.