Numbers
31-35 species north of Mexico
(1)(2), but only three west of Rocky Mountains. Over 300 species worldwide, most of them in Central America and tropical South America.
Identification
The distinctive character of
Condylostylus is a pair of setose mounds on the frons bearing the vertical setae.
(3) When present, wing markings in the form of two bands joined along the costa will distinguish
Condylostylus from other American Sciapodinae. In addition, the following combination of typical, but not universal, characters can help ID the genus:
vertex deeply excavated
M distinctly forked (unforked in Mesorhaga)
frons usually with pale bristles in addition to black (usually only black in Sciapus)
setae of calypter usually black (usually pale in Sciapus)
scutellum with two pairs of bristles (outer pair reduced or absent in Sciapus)
In many species, vein M1 is more sharply curved towards the base of the wing than in other genera.
Range
Tropics of America, Pacific islands, and Africa. Temperate North America
Habitat
Typically found in moist forests
Remarks
Different species are commonly found together, even on adjacent leaves.
Key to species groups found north of Florida and Texas, possibly unreliable for females along the Gulf Coast.
Notes: In some species wing markings are optional. When markings are present they may be faint and not continuous, reduced to darkened areas along veins. The standard U shaped wing pattern is two bands across the wing joined by a band between C and R5. A few species without wing markings may have a faint cloud near the tip of R2+3.
C1. Legs and antennae of both sexes completely black. → C2
C1'. At least part of fore or mid legs beyond coxae yellow or brown. → C4
C2. Male: usually pure blue, costal cell expanded, costa with long cilia, R1 ending distinctly past midwing, second segment of fore tarsi very short. Wing unmarked. Southeast USA, Neotropics. → C. mundus
C2'. R1 not ending past midwing, usually shorter. Wing usually with U-shaped mark. Never completely blue; sometimes with blue reflections. → C3
C3. Face with long, pale hairs. Segments 2-4 of fore tarsi similar (female) or 2-3 similar and 4 longer (male). East of Great Plains → C. patibulatus
C3'. Face bare or with dark hairs. Great Plains to Pacific → C. melampus, C. coloradensis, C. pilicornis.
C4. Antennae longer than head and thorax combined. Fore and mid tibiae with about four very long hairs. Femora of both sexes dark. → C. comatus group (comatus, crinitus, villosus)
C4'. Antennae of normal length. Femora of female usually pale. → C5
C5. Wing with U shaped marking, sometimes very faint or only present along veins → C6
C5'. Wing unmarked, occasionally with cloud near tip of R2+3 → C7
C6. Femora and tibiae of both sexes yellow. East → C. sipho group (six species)
C6'. Femora of male dark. Georgia to Arizona → C. inornatus, C. leonardi, C. quadricolor (unrelated species)
C7. Fore and mid femora of both sexes yellow. Face bare → various rare species
C7'. All femora of male dark, of female yellow or dark. Face bare or with long, white hairs → C8
C8. Tibiae yellow, hind tibia usually darkened near tip. M1 gradually curved, making approximately right angle with base of M. Face usually with pale hair. Male mid basitarsus usually with conspicuous curved bristles. Mid tibia of female with strong bristle near one third length. → C. caudatus group (s.l.)
C8'. Mid basitarsus of male with row of fine hairs. Legs black except fore tibiae of male and fore and mid tibiae of female. Hind tibia of both sexes and mid tibia of male with row of about 12 bristles. Face bare. → C. longicornis
Print References
Charles H. Curran, American Diptera. Bulletin of the AMNH, v. 80, article 3 (1942) (key to
Laxina) (
online at AMNH)