Cyphomyrmex nemei Kusnezov

Kempf, W. W., 1964, A revision of the Neotropical fungus-growing ants of the genus Cyphomyrmex Mayr. Part I. Group of strigatus Mayr (Hym., Formicidae)., Studia Entomologica (N. S.) 7, pp. 1-44 : 39-40

13. Cyphomyrmex nemei Kusnezov

(Figs. 40-43)

Cyphomyrmex nemei Kusnezov , 1957: 7-9, 11 (Worker, female, male; Argentina, Salta: El Rey).

Types. -8 females and 107 males, taken in nuptial flight on February 17, 1953, in the subtropical forest of the valley Soco Hondo, Reserva Nacional Estancia El Rey, Salta Province, Argentina; a lone worker taken separately at the same locality. The types in the Miguel Lillo Museum are either mislaid or lost except for a slide containing 2 males and 2 females. 8 males and 1 female (lectotype) in my collection (WWK).

Worker. - According to the original description, this caste resembles rather closely that of quebradae (= olitor ), differing principally in the lack of a pronotal tubercle, in the laterally immarginate and discally convex mesonotum that lacks the two pairs of tubercles, in the unarmed epinotum that has a very short basal face, in the postero-dorsal contours of the postpetiole, which is less sinuous.

It seems even closer to lectus from which it is separated by the following differences: frontal lobes less expanded, not covering part of the eyes in full-face view; inferior pronotal spine not drawn out; mesonotum as described above; petiole nearly twice as broad as long with conspicuously convex sides; postpetiole more than twice as broad as long, similar to that of " quebradae "; pilosity on tergum of gaster curved and subappressed.

Female (lectotype). - Total length 3.5 mm; head length 0.80 mm; head width 0.69 mm; thorax length 1.04 mm; hind femur length 0.75 mm. Light ferruginous; front and vertex darker. Integument opaque; sharply and finely reticulate-punctate, with sparser and larger punctures all over body and appendages; dorsum of head, scutum and scutellum, dorsum of gaster with superimposed reticula of coarser and intertwined rugulae, predominantly longitudinal on front and vertex and on tergum I of gaster.

Head as shown in Fig. 42. Mandibles with 9 teeth. Frontal lobes converging cephalad, lateral borders straight to feebly impressed. Occipital lobes slightly prominent and set off. Thorax as shown in Fig. 40. Midpronotal tubercle absent, lateral ones low but distinct and subcorneal. Scutellum bluntly bidentate behind, a shallow excision between the teeth. Epinotal teeth weak, basal face of epinotum scarcely distinct from declivous face. Femora carinate and narrowly crested on flexor face, hind femora forming ventrally an angle on basal third, with a low foliaceous crest projecting from posterior border of femora on angle. Fore wing as shown in Fig. 43. Pedicel shown in Figs. 40 and 41. Postpetiole unusually broad as in bruchi and " quebradae ", with a middorsal longitudinal shallow impression, and postero-laterally more deeply impressed. Tergum I of gaster anteriorly marginate, anterior half with a broad and deeply impressed longitudinal furrow, which is traversed by a series of irregular rugulae. Pilosity rather fine, curved and subappressed, subdecumbent on gular face of head and sternum of gaster.

Male as described by Kusnezov (1957).

Discussion. - Since the only known worker of the present species has been collected separately and is to all appearances lost, I select the above diagnosed female as the lectotype. The differential characters for the worker have already been pointed out in the preceding description. The female differs from that of quebradae (previously synonymized with olitor !) in the following characters: frontal lobes not evenly rounded, but forming a blunt angle, converging cephalad in front of angle, straight and slightly impressed. Epinotal teeth extremely feeble. Tergum I of gaster with the deeply impressed sagittal furrow on anterior half, traversed by rugosities. The frontal carinae are as in the olitor types, and do not possess distinctive value. It is quite possible that nemei will eventually end up as synonym of olitor , unless we find another way of dealing with the striking variability of the latter species.