Lioponera neocaledonica

This species was collected on the forest soil at an elevation of 441 m, which corresponds to a mixed humid forest supporting abundant shrubs of the remarkable, endemic basal angiosperm species Amborella trichopoda Baill. (Amborellaceae) as well as ferns of the Marattiaceae, namely Ptisana rolandiprincipis (Rosenst.) Christenh.

Identification
Lioponera neocaledonica is mostly characterized by the combination of the following features: mesosoma dorsolaterally conspicuously marginate, propodeal declivity without dorsal margin; posterolateral corners of petiole not projected into spines. The two latter features easily serve to distinguish L. neocaledonica from the other New Caledonian species Lioponera cohici and Lioponera dumbletoni.

Leptogenys loarelae, together with Leptogenys acutangula and Leptogenys sagaris from New Caledonia, shares affinities with the Leptogenys fauna of Australia and Papua New Guinea. Leptogenys keysseri from Papua New Guinea, is largely similar to L. loarelae, but its petiole is much more narrowed anteriorly.

Distribution based on Regional Taxon Lists
Australasian Region: New Caledonia.

Nomenclature

 *  neocaledonica. Lioponera neocaledonica Jouault, Ramage & Perrichot, in Ramage et al., 2019: 7, figs. 4, 5B (w.) NEW CALEDONIA.

Description
The potential presence of ergatogynes in Lioponera (Wilson 1957; Borowiec 2016) prevents assignment of the present specimens to workers or ergatogynes. However, given that the holotype and 2 paratypes were collected together foraging outside the nest, it is likely they are workers rather than reproductives.

Holotype (in mm; holotype in brackets). TL 4.12–4.15 (4.15); HL 0.8–0.85 (0.85); HW 0.7–0.77 (0.77); SL 0.45–0.52 (0.52); ED 0.2–0.25 (0.2); PW 0.65–0.72 (0.7); MH 0.52–0.62 (0.62); MSL 1.025– 1.12 (1.12); PL 0.45–0.55 (0.55); PH 0.4–0.42 (0.42); DPW 0.67–0.7 (0.7); T1W 0.65–0.77 (0.77); T1L 0.5–0.62 (0.62); T2W 0.75–0.82 (0.82); T2L 0.6–0.65 (0.65). Indices: CI 84–91 (91); SI 64–69 (67); LPI 76–94 (77); DPI 127–150 (127).

HEAD. Sub-rectangular, slightly longer than broad, widest above midline of head; lateral sides slightly convex; vertexal margin slightly concave, posterior lateral corners slightly rounded. Parafrontal ridges angular. Compound eyes of medium size, situated below midline of head. Mandible elongate, triangular, masticatory margin with 10 small teeth. Antennae with scape short and clavate, reaching up to two fi fth of posterior margin of head.

MESOSOMA. Stout, roughly rectangular in dorsal view, with conspicuous dorsolateral margins, the margins notched around promesonotal junction; mesosomal dorsal surface convex, propodeal declivity without dorsal margin.

METASOMA. Petiole broader than long, slightly trapezoidal, widest at two thirds of length; anterior petiolar surface concave; dorsal petiolar surface convex, with dorsolateral margins well developed and convex, without anterodorsal and posterodorsal margins; posterior petiolar surface slightly convex; anterodorsal and posterodorsal corners angular. Subpetiolar process small, triangular, with stout acute somewhat hooked apex; fenestra absent. Gaster elongate, with distinct girdling constriction (cinctus) between abdominal segments III and IV. Abdominal segment II trapezoidal, slightly broader than long, widest at one third of length; dorsal surface slightly convex; dorsolateral margins well developed and strongly convex; anterodorsal margin sinuate; anterodorsal corner broadly rounded; posterolateral corner angular. Sting exerted, upcurved.

INTEGUMENT. Mostly black except last two funicular articles, tarsomeres, and posterior margins of abdominal segments IV to V brown. Body finely and sparsely punctate; reticulation present on sides of the mesosoma, becoming shallower from propleura to propodeum; cinctus, abdominal segment IV, base of abdominal segments V, VI and pygidium transversally, fi nely and shallowly striate. Body covered with suberect hairs; scape with abundant appressed hairs; tibiae with scattered decumbent hairs; tarsi with abundant decumbent to appressed hairs; declivous face of propodeum with short, dense and appressed hairs.

Etymology
The specific epithet refers to New Caledonia where the species was discovered.

References based on Global Ant Biodiversity Informatics

 * Ramage T., C. Jouault, A. R. Schmidt, L. J. Seyfullah, and V. Perrichot. 2019. Two new ant species (Formicidae: Dorylinae, Ponerinae) from New Caledonia. European Journal of Taxonomy 589: 1-14.