OPLOMUS. 29 
larve of a species of Galeruca which feeds on that plant” (Uhler). “It preys upon the 
larva of the Colorado potato-beetle (Doryphora decemlineata). Seven or eight indi- 
viduals of this species were found in the web nest of a social caterpillar, and also were 
seen destroying the larva of Papilo asterius by Mr. Walsh” (Townend Glover, Ill. Ins. 
Or. Hem. p. 68, 1876). 
OPLOMUS. 
Oplomus, Spinola, Ess. Hém. p. 355 (1837) ; Dall. List Hem. i. p. 76. 5 (1851) ; Stal, Ofv. Vet.-Ak. 
Foérh. 1867, p. 496. 
Catostyraz, A. & S. Hist. des Hém. p. 82 (1848). 
This genus is at once separated from the preceding by the shape of the scutellum, 
which is much more angulated and narrowed beyond the middle. The anterior femora 
are armed with a spine near apex; the lateral angles of the pronotum are unarmed ; 
and the abdomen is provided with a basal spine, which reaches the intermediate coxe. 
With the exception of one species recorded from Cuba, this genus is confined to the 
Neotropical Region, and is found in the Central-American, Colombian, Amazonian, and 
South-Brazilian Subregions. About two thirds of the known species are found in 
Central America, and are all exceedingly variable. Whether these species are poly- 
goneutic, and whether these variations are seasonal, must be left to the decision of the 
local observer; but it is at least singular that all the varieties of each species start 
from, or tend to, one unicolorous form. 
A. Head emarginate in front, the lateral lobes distinctly longer than the central lobe. 
1. Oplomus dichrous. (Tab. I. fig. 16.) 
Asopus dichrous, Herrich-Schaffer, Wanz. Ins. iv. p. 89, fig. 4267. 
Asopus rhodomelas, H.-S. Wanz. Ins. iv. p. 90, fig. 4287. 
Oplomus rubropictus, Voll. Tijdschr. voor Ent. vi. p. 121. 1. 
Oplomus (Polypecilus) dichrous, Stal, Ent. Hem. pt. 1, p. 26°. 
Hab. Mexico 1?3, Oaxaca (Mus. Berol.). 
The various forms of this species may be described as follows :— 
Var. a. Typical. 
The abdomen beneath is unicolorous, with the exception of the ventral spine and accompanying basal spot, which 
are either luteous or testaceous. 
Var. 6. 
Differing from var. a by the first, second, and base of the third joints of the antennz, rostrum, and legs being © 
luteous or testaceous (Stal). 
we 
Var. ¢. 
Greenish black ; pronotum with anterior and lateral borders and narrow central longitudinal fascia, scutellum 
