Cephalotes olmecus

A fossil species known from Mexican amber.

Identification
A member of the grandinosus clade differing from all the other species of the clade in the worker by the presence of a narrow, crenulate crest on the dorsum of the fore femora, and in the soldier by the strongly crenulate carinae on the dorsum of the fore femora. (de Andrade and Baroni Urbani 1999)

Key to Cephalotes Workers

Distribution
This taxon was described from Mexican amber.

Nomenclature

 * † olmecus. †Cephalotes olmecus De Andrade, in De Andrade & Baroni Urbani, 1999: 425, figs. 15A-B, 194, 195 (s.w.) MEXICAN AMBER.

Worker
Head broader than long. Frontal carinae weakly and minutely erenulate. Vertexal angles broad, round and membranaceous. Vertcxal margin concave. Mandibles with lateral carina. Antennal club two jointed.

Mesosoma. Scapular angles absent or not visible in dorsal view. Anterior pronotal border straight; pronotal sides with a broad, membranaceous expansion, anteriorly subround and narrowing posteriorly. Promesonotal suture absent. Mesonotal sides with a pair of triangular, membranaceous teeth. Propodeal suture deeply impressed. Deelivous face of the propodeum gently sloping backwards. Basal and deelivous faces of the propodeum with a broad membranaceous expansion originating cranially on the basal face and broadening backwards; margin of the membranaceous expansion of the propodeum minutely and superficially crenulate.

Petiole with the anterior face truncate; sides of the petiole with a broad, round, wing-shaped, membranaceous expansion directed laterally. Postpetiole with a comparably broad, wing-shaped, membranaceous expansion with round apex and directed forwards.

Gaster suboval and with broad, anterolateral, membranaceous expansions not surpassing the stigma backwards.

Mid and hind femora angulate and with two membranaceous crests on the two distal thirds, one on the dorsal face and another on the ventral face; fore femora with a short dorsal crest. Mid and hind basitarsi with flat and broad base.

Sculpture. Head dorsum, mesosoma and pedicel minutely reticulate and foveolate, the foveae larger and more regular on the frons, very irregular on the mesosoma, small on the propodeum and on the pedicel. Pronotum and mesonotum with short rugosities between the foveae. First gastral tergite and legs strongly reticulate, the same type of sculpture but more superficial on the first gastral sternite. Anterior half of the first gastral tergite with thin, longitudinal rugosities

Pilosity. Some fovea with a recurved hair. Sides of the frontal carinae, border of the mesosomal and of the peduncular expansions, and legs with short hairs.

Colour. Light brown. Frontal carinae, vertexal angles and membranaceous expansions light ferruginous and semitransparent.

Measurements (in mm) and indices: TL 3.60; HL 0.83; HW 1.07; EL 0.22; PW 0.82; PeW 0.47; PpW 0.53; HBaL 0.20; HBaW 0.12; CI 128.9; PI 130.5; PPeI 174.5; PPpI 154.7; HBaI 60.0.

Type Material
Holotype worker from the Mexican amber sample Mex. 1 and paratype small soldier from the Mexican amber sample H 10-201, both in the GOPC.

Etymology
This species is named after the Olmecs, one of the ancient peoples of Mexico.