Chlerogas Vachal, 1904

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 : 37-39

Genus Chlerogas Vachal

Chlerogas Vachal, 1904: 127 . Type species: Halictus chlerogas Vachal, 1904 , monobasic and absolute tautonymy.

DIAGNOSIS: The elongate heads produced by a greatly lengthened malar space serves to separate Chlerogas from other Augochlorini except the genera Chlerogella and Ischnomelissa . The genera, however, are not related and although Chlerogas resembles the latter two in the structure of the head, this genus is unique for the pectinate inner hind tibial spur of the male, the reduced flagellomere count, the shorter propodeal basal area, and the larger body sizes.

DESCRIPTION: Female. Mandible with moderately defined subapical tooth. Labral distal process narrowly triangular; basal elevation orbicular; teeth absent. Prementum not greatly elongate. Galeal apex rounded galeal comb absent; galeal base extending to

base of stipes. Hypostomal ridge carinate; anterior angle rounded. Malar space much longer than basal mandibular width. Epistomal sulcus very slightly acute, only a little less than 90°. Flagellum with only 9 flagellomeres. Ocelli not greatly enlarged; ocellar furrow absent. Vertex not expanded or ridged behind ocelli. Preoccipital ridge angled. Pronotal lateral angle not produced, obtuse; dorsal ridge angled; lateral ridge rounded. Mesoscutal anterior border rounded; mesoscutal lip rounded. Tegula oval. Anterior basitarsal brush present. Basitibial plate border on all sides. Inner hind tibial spur pectinate. Apex of marginal cell acute. Distal hamuli with irregular spacing pattern. Basal area of propodeum about as long as scutellum, granular or striate; propodeal pit narrow. Male. Mandible simple. Labrum with short distal process; basal area not notched. Antennae long, extending back to propodeum; flagellum with only 10 flagellomeres. Inner hind tibial spur pectinate. Metasoma elongate. Apical margins of S4–S5 concave. Apical margin of S6 emarginate. Apical margin of S7 with median projection. Apical margin of S8 with median projection; spiculum broad. Proctiger unmodified. Gonobasal bridge narrow; dorsal lobes moderately developed. Parapenial lobe and basal process of gonostylus absent; dorsal process a large lightly melanized mass. Volsella indented on inner margin at base of digitus; digitus sometimes elongated apically. Ventral surface of penis valve unmodified.

REVISIONS: The genus has recently been revised by Brooks and Engel (1999) who recognize nine species.

BIOLOGY: Nothing is known of Chlerogas biology, although Brooks and Engel (1999) speculated that the elongate heads are an adaptation for tubular flowers.

DISTRIBUTION: Species of Chlerogas are found throughout northern South America, although the range of any single species is seemingly restricted. Species are known from the mountains of Bolivia, Colombia, Ecuador, Peru, and Venezuela.

Genus Chlerogella Michener

Figures 4 , 37 , 39 , 46, 50 Chlerogella Michener, 1954b: 75 . Type species:

Chlerogella elongaticeps Michener, 1954b ,

monobasic and original designation.

DIAGNOSIS: The genus Chlerogella is most similar and closely related to the genera Chlerogelloides and Ischnomelissa , sharing with these genera the elongate propodeum. From the former Chlerogella differs in the elongate malar space, the pectinate inner metatibial spur, strong basitibial plate, and in the structure of the epistomal sulcus; while from the later genus Chlerogella differs in the normal pectinations of the inner metatibial spur, the acute epistomal sulcus, and the inflated dorsal surface of the pronotum.

DESCRIPTION: Female. Mandible with moderately developed subapical tooth. Labral distal process narrowly triangular; basal elevation orbicular to bilobed; teeth absent. Prementum not greatly elongate. Galeal apex rounded; galeal comb absent; galeal base extending to base of stipes. Hypostomal ridge carinate; anterior angle rounded. Length of malar space as long as or frequently longer than basal mandibular width. Epistomal sulcus acute. Ocelli not greatly enlarged; ocellar furrow absent. Vertex not expanded or ridged behind ocelli. Preoccipital ridge rounded. Pronotal dorsal surface frequently inflated, rendering lateral ridge and angle obsolete; dorsal ridge rounded. Mesoscutal anterior border rounded; mesoscutal lip absent. Tegula oval. Anterior basitarsal brush present. Basitibial plate bordered on all sides. Inner hind tibial spur pectinate. Apex of marginal cell acute. Distal hamuli with irregular spacing pattern. Basal area of propodeum longer than scutellum, smooth to granular; propodeal pit narrow. Male. Mandible simple. Labrum without distal process; basal area not notched. Antennae long, extending back to posterior border of propodeum; F2 longer than F1. Inner hind tibial spur serrate. Metasoma elongate. Apical margin of S4 emarginate. Apical margin of S5 unmodified. Apical margin of S6 emarginate. Apical margin of S7 with median projections. Apical margin of S8 with median projection; spiculum narrow. Proctiger unmodified. Gonobasal bridge narrow; dorsal lobes weak. Parapenial lobe and basal process of gonostylus absent. Ventral surface of penis valve with prong.

REVISIONS: A revision of Chlerogella is being completed by Brooks and Engel (in prep.) and currently recognizes 17 species (15 new to science), although one, Chlero- gella bouyssoni (Vachal), is uncertainly placed in the absence of the holotype (Engel, personal obs.).

BIOLOGY: The biology of Chlerogella remains undiscovered. The elongate heads may indicate an association with flowers possessing deep corollas similar to that hypothesized for species of Chlerogas (Brooks and Engel, 1999) .

DISTRIBUTION: Species of Chlerogella are distributed throughout southern Central America and northern South America. Their range includes mountainous regions of the following countries: Bolivia, Colombia, Costa Rica, Ecuador, Panama, Peru, and Venezuela.

Figures

Figs. 1–6. Heads of Augochlorini, frontal aspect. 1. Thectochlora alaris (Vachal), female. 2. Rhinocorynura briseis (Smith), female. 3. Megommation (Cleptommation) minutum (Friese), female. 4 Chlerogella sp., female. 5. M. (Megaloptina) ogilviei (Cockerell), female. 6. Megalopta (Megalopta genalis Meade-Waldo, male.

Figs. 34–37. Characteristics of female Augochlorini. 34. Tegula of Augochloropsis (Paraugochloropsis) sumptuosa (Smith), depicting notch on inner posterior margin. 35. Tegula of Rhinocorynura briseis (Smith). 36. Distal hamuli of hind wing of Megalopta (Megalopta) genalis Meade-Waldo. 37. Distal hamuli of Chlerogella sp.

Figs. 38–41. Features of female Augochlorini. 38. Scutellum, metanotum, and basal area of propodeum of Megommation (Cleptommation) minutum (Friese). 39. Scutellum, metanotum, and basal area of propodeum of Chlerogella sp. 40. Hind leg of Temnosoma metallicum Smith, scopa absent from femur and tibia. 41. Hind leg of Augochlora (Augochlora) pura (Say), scopa on femur and tibia.

Figs. 46–51. Spurs and antenna cleaners of female Augochlorini. 46. Inner hind tibial spur of Chlerogella sp. 47. Inner hind tibial spur of Thectochlora alaris (Vachal). 48. Inner hind tibial spur of Augochlora (Augochlora) pura (Say). 49. Inner hind tibial spur of Pereirapis semiaurata (Spinola). 50 Antenna cleaner of Chlerogella sp. 51. Antenna cleaner of Megommation (Cleptommation) minutum (Friese).