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Polyrhachis (Myrma) aerope HNS , new species
Text Figure 72c and d
Length somewhat less than 6 mm.
Head longer than broad, subelliptical, not broader behind than in front, narrowed behind the eyes to the occipital border, which is indistinctly marginate, very convex in the middle above through the frontal carinae, the cheeks rather straight, the gular margin bluntly submarginate. Eyes at the middle of the sides of the head, large, prominent, broadly elliptical, their external orbits slightly sinuate. Mandibles narrow, their apical borders rather oblique, with five subequal teeth. Clypeus convex, bluntly carinate in the middle, its anterior border broadly rounded, entire. Frontal area broadly triangular, indistinct; frontal carinae high, rather closely approximated, moderately sinuate, somewhat farther apart and subparallel behind. Antennae long, scapes slightly enlarged and deflected at their tips, extending fully one-half their length beyond the posterior border of the head. Thorax much like that of P. concava Ern. Andre HNS , long and narrow, the dorsal surface concave with strong, upturned lateral carinae, notched at the pronounced, transverse premesonotal and mesoepinotal sutures. Pronotum as long as broad, narrowed behind, its anterior spines straight, acute, slightly divergent, flattened, more than twice as long as their width at the base. Mesonotum trapezoidal like the pronotum, but smaller and broader than long; base of epinotum regularly rectangular, one and one-third times as long as broad, its posterior corners with two small, erect, slightly recurved teeth, which are as long as broad at their bases, its posterior border not marginate but, as in concava HNS , passing over into the sloping declivity, which is slightly longer than the base and feebly convex in profile. Petiole and gaster shaped as in concava HNS , but with the median pair of spines of the former straight, when seen from the front, and not slightly curved inward. Tibiae distinctly constricted at their bases.
Shining; gaster smooth and polished. Mandibles finely striated and sparsely and finely punctate; head, thorax, and petiole finely coriaceous or shagreened; the clypeus somewhat smoother. Gaster very minutely and superficially punctate.
Hairs and puheseenee whitish, the former erect, very sparse, present only on the tip of the gaster and posterior portion of venter; the pubescence very short and dilute, delicate, and appressed, visible only nn the sides of the thorax and on the clypeus and appendages.
Black; only the palpi and insertions of the antenna; reddish.
Described from a single specimen from the stomach of a frog (Xenopus mulleri) taken at Niangara (Lang and Chapin).
This form is so close to concava HNS Andr- that it might be regarded as a subspecies. It differs, however, very decidedly in the proportions of the head and thorax, as shown in the accompanying figures, and is also smaller ( concava HNS measures nearly 7 mm); the pubescence on the body is much less developed and the legs are darker.