Mycetarotes

Caaguazú , Canindeyú (ALWC, IFML, INBP, LACM, USNM).

Cyphomyrmex subgenus Mycetarotes Emery, 1913: 251. Type of the subgenus:

Cyphomyrmex parallelus Emery , 1905, by original designation. - Emery, 1922: 342-343.

Mycetarotes , Borgmeier, 1950: 384.

Worker - Monomorphic. Mandibles striolate, with 5-6 teeth. Antennae 11-segmented; funiculus without a differentiated apical club. Frontal carinae convex in front, prolonged to the rear as a pair of subparallel ridges, bifurcating before reaching the occiput; inner branch terminating as a prominent denticle, outer branch weaker or vestigial. Space between these ridges narrower than space between each ridge and the sides of head. Carinule on gena fine to vestigial, curving mesad posteriorly at level of eyes. A clearly delimited antennal scrobe absent. Occipital corners tridentate. Thorax with 6-7 pairs of teeth or spines on dorsum; posterior epinotal spines long and acute. Petiole with a pair of spines dorsally near the posterior border. First gastric tergite anterolaterally marginate. Integument opaque, lacking coarse sculpture; dorsum of head, postpetiole and gaster sharply reticulate-punctate. Erect hairs absent. Appressed hairs sparse.

Female - Similar to the worker. Posterior ocelli situated laterad of longitudinal ridges of vertex. Thorax with a humeral spine on pronotum; scutum with a median longitudinal furrow and parapsidal sutures; scutellum posteriorly bidentate. Epinotal spines well-developed. Venation of fore wing of the Formica-type; pterostigma small but well-defined.

Male - Antennae 12-segmented; scape shorter than funicular segments I-III combined, no reaching back to the tridentate occipital corner. Thorax with Myrmicocrypta-like tuberosities and appendages on scutum and scutellum, but lacking the pair of sharp longitudinal ridges on scutum. Humeral and epinotal spines well-developed. Pedicel resembling that of worker. First gastric tergite with a pronounced longitudinal impression in the middle. Standing hairs absent. Wings as in female.

Workers and females differ strikingly from Cyphomyrmex in head shape, especially in lacking a well-defined and impressed antennal scrobe. The posterior ridges, prolongations of the frontal carinae, do not run to the occipital corners, but are subparallel and terminate near the middle of the occipital border, forming a tooth at each side of a median excision. The relative slenderness of the strongly dentate or spinous thorax and the dorsally bidentate petiolar node are likewise good distinguishing characters.

The male sex diverges from that of Cyphomyrmex by the relatively short scape which, when laid obliquely back, does not attain the occipital corner, by the first funicular segment, which is distinctly shorter than the second, and by the strongly developed tuberosities and appendages of the mesonotal scutum and scutellum. As regards this mesothoracic armature, it resembles more closely the male of Myrmicocrypta , but the latter genus has the scape somewhat longer (nearly attaining the edentate occipital corner), the first funicular segment only half as long as the second, the mesothoracic scutum with a pair of longitudinal sharp rigdes; the pterostigma of the fore wing is at best rudimentary.

In a critique of Emery's classification, Forel (1913) refuses to recognize the subgenera Mycetarotes and Mycetophylax which to his mind were merely based on a subjective appraisal of the worker characters. The discovery of the male of Mycetarotes proves now that Emery's surmise was not only correct but also shows conclusively that Mycetarotes is generically independent from Cyphomyrmex .

KEY TO MYCETAROTES SPECIES - WORKERS

1 - Thoracic dorsum with 7 pairs of teeth or spines, three pairs on mesonotum; anterior margin of clypeus notched in the middle .......................... senticosussp. n.

- Thoracic dorsum with 6 pairs of teeth or spines, two pairs on mesonotum; anterior margin of clypeus entire ......................................... parallelus (Emery)