28 
Psyche 
[Vol. 93 
vince, Termas de Rio Hondo, Dique Frontal, 3-V-1972, 2-VIII- 
1973, C. Porter; La Rioja Province, Villa Union, 22-IV-1972, C. 
Porter; Cordoba Province, La Lejania ca. Nono, 23-25-X-1984, C. 
Porter, T. O’Neill. 
Relationships. As discussed under that species, Compsocryp- 
tus melano stigma much resembles C. fuscofasciatus of the Peruvian 
Coastal Desert. The two species may have originated from a com- 
mon ancestor that once ranged across what is now subtropical 
South America from north Argentina to the Pacific coast. Warm, 
seasonally dry conditions, of a type preferred by most modern 
Compsocryptus, apparently prevailed across this area during the 
early Tertiary (Solbrig 1976:42). Subsequent Andean uplift would 
have split early Compsocryptus , populations into eastern and west- 
ern isolates, setting the stage for differentiation of the modern C. 
melanostigma in Argentina and C. fuscofasciatus in coastal Peru. 
Field Notes. This conspicuous species occurs throughout 
northern Argentina below 1500 m and ranges into adjoining parts of 
Brasil and Paraguay. It occupies many forest, thorn scrub, and 
desert biomes, including Southeast Brasilian Wet Forest, subtropi- 
cal Andean Cloud Forest, Chaco Forest, Wet Chaco, Dry Chaco, 
Montane Chaco, and Subandean Desert. In wooded areas, C. mela- 
nostigma prefers disturbed situations in full sun along trails or at the 
forest edge. In all habitats, it flies mostly near the ground among 
grasses, forbs, or low shrubs. 
Compsocryptus melanostigma often is very common during fall 
and winter but may be collected in most habitats at any time of the 
year. 
This is the only Compsocryptus for which host information has 
been obtained. It has been reared from the noctuid moths Alabama 
argillacea and Pseudaletia unipunctata (Townes 1966:77). 
3. Compsocryptus fasciipennis (Brulle) 
(Fig. 6) 
Cryptus fasciipennis Brulle, 1846. In Lepeletier: Histoire naturelle des insectes. 
Hymenopteres 4:191. Lectotype $ (labeled by H. K. Townes Townes): Cuba 
(Paris). 
This elegant species was well characterized by Townes (1962: 
282-3). It differs from other Compsocryptus by its bluish black 
