Epelysidris

The single species of this genus, Epelysidris brocha, is known from workers that have been found in the soil of a moss forest and tropical rainforest (as stated on the labels from the two known collections).

Identification
Bolton (1987) - Epelysidris is easily diagnosed among members of the Solenopsis-group by the remarkable pair of lobes on the basal border of each mandible, unknown in any other genus of the group. The structure of the mandibles and clypeus together, combined with the 3,2 palp formula, isolates Epelysidris from all other myrmicine ant genera. Conversely characters regarded as apomorphic in Epelysidris include the development of lobes on the mandibular basal margin, the presence of large triangular teeth on the anterior clypeal margin, and the development of narrow cuticular crests down each side of the propodeal declivity. The M. modestus-group is plesiomorphic in these, with unarmed basal mandibular margins, lacking clypeal teeth, and lacking cuticular crests on the propodeal declivity.

The real affinities of Epelysidris appear to lie with Monomorium and its immediate allies, from which it has evolved by gross modification and specialization of the mandibles and clypeus. Differences in the mandible between Epelysidris and those Monomorium species with 5 teeth include lengthening and narrowing of the blade in the former and the opening of diastemata between the teeth following the preapical, and the autapomorphic development of lobes on the basal border. In the case of the clypeus Epelysidris has modified the median portion by narrowing and raising it up very markedly, and narrowing its posterior section between the antennal insertions. The pair of longitudinal clypeal carinae, characteristic of Monomorium, is very reduced and fades out anteriorly in Epelysidris. On the other hand the pair of teeth on the anterior clypeal margin, which mark the apices of the clypeal carinae in many Monomorium species, are very much enlarged in Epelysidris and are divorced from the carinae altogether.

Biology
See the biology section of Epelysidris brocha for observations of the only collected colony of this genus.

Nomenclature

 *  EPELYSIDRIS  [Myrmicinae: Solenopsidini]
 * Epelysidris Bolton, 1987: 279. Type-species: Epelysidris brocha, by original designation.
 * Epelysidris junior synonym of Monomorium: Fernández, in Heterick, 2006: 79; Fernández, 2007b: 130.
 * Epelysidris revived from synonymy: Ward et al., 2014: 15.

Worker
Bolton (1987) - Monomorphic myrmicine ants. Palp formula 3.2. Mandibles elongate-triangular, the masticatory margin with 5 sharp teeth which scarcely decrease in size from preapical to basal; preapical to basal teeth separated by diastemata. Basal border of mandible equipped with two broad-based bluntly triangular lobes, the first close to the basalmost sharp tooth and the second near the trulleum. Trulleum large, deformed-triangular in shape and narrowly open below base of second lobe on mandibular basal margin. Anterior clypeal margin with a pair of stout triangular teeth. Median clypeal seta present. Anterior tentorial pits about half way between antennal sockets and lateral margins of head. Median portion of clypeus narrow and conspicuously raised, the convex raised section feebly bicarinate posteriorly and the carinae tending to fade out anteriorly. Antennal insertions close together, the width of the posterior portion of the clypeus where it passes between the frontal lobes approximately equal to the width of one of the frontal lobes. Antennae 12-segmented with a strongly differentiated club of 3 segments. Frontal carinae and antennal scrobes absent. Eyes present, small, situated at the midlength of the sides. Promesonotum strongly convex, without dorsal sutures. Metanotal groove present and impressed. Propodeal spiracle large and circular, close to the midlength of the sclerite. Metapleural glands of moderate size, not hypertrophied. Propodeum unarmed but a narrow longitudinal cuticular rim or crest present where dorsum meets declivity, the crest continued down each side of the declivity to the small rounded metapleural lobes. Declivity without a transverse carina linking the dorsalmost points of the metapleural lobes. Petiole with a long anterior peduncle which is subtended by a narrow elongate ventral processes. Petiolar spiracle at the node. Nodes of both petiole and postpetiole strongly developed, shaped as in Fig. 16. Sting long and strong, somewhat flattened and subspatulate apically.