Loboponera Bolton & Brown

Loboponera Bolton & Brown

Fig. 38

Loboponera Bolton & Brown, 2002: 3 (as genus in Ponerini). Type-species: Loboponera vigilans Bolton & Brown, 2002: 7; by original designation.

Loboponera is a small (nine described species) Afrotropical genus. They are cryptic nesters and foragers, but nothing else is known about their habits.

Diagnosis. Loboponera workers are readily identified by their huge frontal lobes, cuticular flanges at the posteroventral corners of the head, obsolete metanotal groove, broad propodeum, dorsal longitudinal grooves on the meso- and metafemora, and strongly arched tergite A4. Loboponera is most similar to Plectroctena, Boloponera, Psalidomyrmex, Feroponera, and some Bothroponera, but none of these other genera have posteroventral flanges on the head or a strongly vaulted gaster. Plectroctena has dorsal grooves on its meso- and metafemora, and Boloponera also has grooves on its metafemora (this is undoubtedly a synapomorphy of these three genera), but these genera both have linear mandibles, in contrast to Loboponera’s more triangular mandibles. Bothroponera has two metatibial spurs, among many other differences. Feroponera and Loboponera both have a pair of teeth on the anterior clypeal margin, but Feroponera has stout traction setae on its mesotibiae and meso-/ metabasitarsi, and lacks eyes.

Synoptic description. Worker. Small to medium (TL 3.0– 7.5 mm) robust ants with the standard characters of Ponerini. Mandibles triangular to subtriangular, with a basal groove. Anterior margin of clypeus with a blunt medial projection and laterally with a tooth projecting over each mandibular articulation. Frontal lobes greatly expanded laterally and closely approximated. Antennae moderately clubbed apically. Eyes very small, located far anterior of head midline. Posteroventral corners of head with cuticular flanges. Mesopleuron divided by a transverse groove, the anepisternum often appearing fused to the mesonotum and metapleuron. Metanotal groove absent. Propodeum broad dorsally, the posterolateral margins often forming lamellae. Propodeal spiracles round. Metapleural gland orifice opening laterally. Meso- and metafemora with a dorsal longitudinal groove. Metatibial spur formula (1p). Petiole nodiform. Anteroventral articulatory surface of petiole long and broad, with a narrow median groove. Strong girdling constriction present between pre- and postsclerite of A4. Tergite of A4 strongly vaulted and down-curved posteriorly. Head and body shining, foveolate to punctate, sometimes with some longitudinal striations on the sides of the mesosoma, and generally with sparse pilosity and pubescence. Color dark red or purple to nearly black.

Queen. Similar to workers but slightly larger, winged and with the characters typical of alate ponerine queens (Bolton & Brown, 2002).

Male. Unknown.

Larva. Undescribed.

Geographic distribution. Loboponera is restricted to central and western Africa, ranging from Ivory Coast to Rwanda (Bolton & Brown, 2002; Fisher, 2006).

Ecology and behavior. Virtually nothing is known about the ecology or behavior of Loboponera. Collections of this genus have come from leaf litter and rotting wood (Bolton & Brown, 2002; Fisher, 2006), which when paired with its reduced eyes and downcurved gaster (possibly an adaptation to hunting in tight spaces) strongly implies a cryptic lifestyle. Their generalized mandibular structure gives no clues to the identity of their prey.

Phylogenetic and taxonomic considerations. Loboponera was erected by Bolton & Brown (2002) to house several newly described species as well as Pachycondyla (Bothroponera) nasica (Santschi). Bolton & Brown linked Loboponera to Plectroctena and Psalidomyrmex based on the shape of the anteroventral articulatory surface of the petiole, and suggested that the presence of longitudinal grooves on the meso- and metafemora was synapomorphic for Loboponera and Plectroctena. Schmidt's (2013) molecular phylogeny of the Ponerinae confirms the sister relationship between Loboponera and Plectroctena and likewise their sister relationship to Psalidomyrmex, at least among the sampled taxa. We believe that Boloponera is probably sister to either Loboponera or Plectroctena, or to both together, in disagreement with Fisher (2006). See the earlier discussion of phylogenetic relationships within the Plectroctena group for more on this.