MORGAN HEBARD 197 



Generally similar to aptera aptera Scudder. Size small, form moderately 

 robust for the species. Head moderately large in proportion to size of 

 body, vertex very small, frontal costa in dorsal aspect very broad and 

 almost transverse in outline, frontal costa strongly sulcate throughout. 

 Eyes large, deep and prominent. Pronotum dorsad and laterad, pleura, 

 mesonotum and metanotum thickly and shallowly impresso-punctate. 

 Tegmina vestigial, represented by minute inconspicuous scales, which 

 project only as far as mesad on mesonotum. Tympana large. Prosternal 

 spine elongate cylindro-conical with apex rounded. Furcula represented 

 by a pair of minute divergent fingers, each scarcely longer (individually 

 varying to no longer) than wide. Cercus simple, slightly over twice as long 

 as broad, tapering to the acute apex, distad with dorsal margin feebly 

 convex and ventral margin almost straight, very faintly concave. Supra- 

 anal plate shield-shaped (in some paratypes rather narrow, with lateral 

 margins weakly convergent, then rounding sharply into the only slightly 

 produced distal portion), these margins not at all (to slightly in paratypes) 

 thickened proximad, medio-longitudinal sulcus present only in proximal 

 half but deep, lateral portions concave. Paraprocts large, simple. Eighth 

 sternite very large. Subgenital plate represented by a narrow chitinous 

 ring bounding that sternite caudad, which is only a little broader mesad 

 than laterad, bearing within dorso-proximad on each side a large fleshy 

 rounded flap which normally rests over the base of the penis, but springs 

 upward and outward when that organ is extruded. Pseudosternite with 

 dorsal lobes each having a stout short inner finger and an outer ridge 

 which projects less. Penis with very large base, each of dorsal lobes 

 shagreenous, their lateral margins converging moderately dorsad then nearly 

 straight so that very weak marginal concavity is shown. These lobes are 

 flattened and not at all bulbously bilobate as is the case in aptera borealis; 

 dorsal pair of parameres greatly enlarged and specialized, in dorsal aspect 

 appearing as adjacent, shagreenous, rounded, wedge-shaped surfaces much 

 as in aptera borealis but narrower (decidedly broader in males from San 

 Pablo). 



Allotype. — $ ; same data as type. [Hebard Collection]. 



Much larger and decidedly more robust than male. Distinguishable from 

 immatures by the perfectly developed ovipositor valves and (from all 

 immatures except the last instars) by the minute, scale-like tegmina. 

 Prosternal spine heavier. Ovipositor valves with apices moderately elong- 

 ate, the dorsal pair recurved, their external margins irregularly dentate, 

 coarsely so distad, a transverse dorsal flange delimiting distal portion at 

 base, the surface of which portion is strongly concave proximad. 



General coloration delicate green in life, usually fading to yellow-brown 

 or brown in drying, but a brown color phase also occurs. Males with 

 lateral margins of pronotal disk and abdomen medio-longitudinally dorsad 



TRANS. AM. ENT. SOC., LXII. 



