Cephalotes brevispineus

One of a number of Cephalotes fossil species that are known from Dominican amber.

Identification
A member of the basalis clade characterised by the broad vertexal lamella of the worker. Cephalotes manni with which it shares the basal face of the propodeum with three denticles differing in size and the ventral face of the head finely and superficially reticulate. On the other hand, C. brevispineus can be easily differentiated from manni by the shape of the vertexal angles and of the pronotal lamellae. The large workers of manni resemble much more brevispineus in the propodeal and pronotal morphology than the smaller ones. (de Andrade and Baroni Urbani 1999)

Key to Cephalotes Workers

Distribution
This taxon was described from Dominican Amber (Miocene).

Nomenclature

 * † brevispineus. †Cephalotes brevispineus De Andrade, in De Andrade & Baroni Urbani, 1999: 240, figs. 14A, 99 (w.) DOMINICAN AMBER (Miocene).

Worker
Head slightly broader than long. Vertexal angles with a round, broad lamella. Vertex without denticles. Vertexal margin concave. Mandibles laterally angulate.

Mesosoma. Scapular angles absent. Anterior pronotal border strongly protruding anteriorly. Pronotal sides with a broad, long, continuous, triangular lamella narrowing posteriorly. Promesonotal suture absent. Sides of the mesonotum armed with a pair of broad, short, round teeth. Propodeal suture superficially impressed. Propodeum with differentiate basal and declivous faces; basal face with two pairs of short, broad, irregular denticles followed by a pair of pointed teeth; declivous face converging posteriorly.

Petiolar lateral expansions lost in the unique specimen. Anterior petiolar face truncate. Postpetiolar sides anteriorly with a broad, round tooth.

Gaster suboval and with a pair of anterolateral lamellae.

Hind femora angulate. Mid and hind basitarsi flat.

Sculpture. Head, mesosoma and peduncular segments minutely reticulate and with small, superficial foveae variably clumped; the reticulation less impressed on the propodeum and on the pedicel; the foveae sparser and more superficial on the pedicel. Pleurae, gastral tergites and legs reticulate, the reticulation less impressed on the centre of the first gastral sternite. Pilosity. Each fovea with a minute, appressed hair. Border of the vertexal angles, of the pronotal lamellae with rare, short clubbed hairs. First gastral sternite with long, rare, suberect, pointed hairs.

Colour. Black. Frontal carinae, vertexal angles, border of the pronotal lamellae and gastral lamellae ferrugineous.

Measurements (in mm) and indices: TL 5.08; HL 1.20; HW 1.47; EL 0.30; PW 1.47; PeW 0.42; PpW 0.60; HBaL (left) 0.40; HBaL (right) 0.50; HBaW (left) 0.17; HBaW (right) 0.15; CI 122.5; PI 100.0; PPeI 350.0; PPpI 240.0; HBaI 42.5 (left); HBaI (right) 30.0.

Type Material
Holotype worker (unique) in the Dominican amber sample H 10-105 in the GOPC.

Etymology
From the Latin brevis (= short) and spineus ( = bearing spines) referred to the morphology of the propodeal spines.