252 PROCEEDINGS OF THE NATIONAL IVIUSEUIVI vol. los 



narrow, almost twice as long as %dde, with very acute anterior margin, 

 rounded backwards, divided beneath the middle by an oblique, some- 

 what cm-ved vein; diagonal vein as long as the internal margin of the 

 mirror; chords much longer, feebly curved, very close one to the 

 other ; apical field very short ; Sc bearing two branches. Wings exceed- 

 ing very much the elytra, whitish. 



Dimensions (in millimeters): Length of body, 9 9.0, cT 7.5; length 

 with wings, d" 13; pronotum, 2.0; posterior femur, 9 7.0, cf 5.0; 

 elytra, 9 6.0, cT 2.0; ovipositor, 5.5. 



Trigonidomitnus sernyi (Chopard) 



Quarequa zernyi Chopard, Ann. Naturh. Mus. Wien, vol. 4(5, p. 246, fig. 9, 1933. 

 Specimens examined: PERt;: Tingo Maria, November 1949 (19), 

 Allard. 



Family PHALANGOPsroAE 



Key to the Americau genera 



1. Pronotum wider than long, with lateral lobes square or rounded, not attenu- 



ated in front 2 



Pronotum long, with lateral lobes narrowing in front, their inferior margin 

 ascending forwards Cophus Saussure 



2. Frontal rostrum between the antennae wide; inferior margin of the lateral 



lobes of pronotum straight; last joint of maxillary palpi obliquely truncated 



at apex; legs short (Z/Mzorae group) 3 



Frontal rostrum between the antennae narrow; inferior margin of the lateral 

 lobes of pronotum ascending backwards 21 



3. Elytra well developed, their structure delicate; venation conspicuous, dorsal 



field of male deplanate 4 



Elytra moderately to greatly reduced or absent; when present, with structure 

 chitinous, often corneous; venation of dorsal field weak or obsolete . . 7 



4. Lateral field of male tegmina specialized ; Sc with numerous branches . . 5 

 Lateral field of male tegmina with simple venation; Sc without oblique 



branches Prosthacusta Saussure 



5. Anterior tibiae with foramina on both faces; male tegmina ample, widening 



behind ^ 



Anterior tibiae with foramen on internal face only; male tegmina not 

 widening caudad Lernecella Hebard 



6. Superointernal apical spur of posterior tibiae longer than the median; tibiae 



armed with four spines on each margin; mirror of male elytra triangular; 



apical field provided with longitudinal veins Lerneca^Walker 



Superointernal apical spur of posterior tibiae shorter than the median; tibiae 

 armed with three spines on the external margin, one on the internal, with 

 very strong denticles before the spines; mirror of male elytra almost oval; 

 apical field with transverse veins Benoistiella Uvarov 



7. Anterior tibiae with auditory foramina on one or both faces 8 



Anterior tibiae without auditory foramina 18 



8. Tegmina with lateral field having two unbranched longitudinal veins . . 9 

 Tegmina with lateral field having more than two lonfjitudinal veins (some 



of which branch in the males) 12 



