Leptogenys falcigera

Nomenclature

Species: Leptogenys falcigera Roger 1861

Usage: valid

Syntype: BMNH - ANTC4524 - CASENT0102272

General description

Little is known about the biology of L. falcigera. It occurs mainly in low elevation sites on Hawaii (Reimer, 1994), and the average elevation for specimen collections included in Antweb (mostly from Madagascar) is 59 m. Colonies are mostly limited to fewer than 50 workers (Reimer, 1994). Like most of its congeners the queens of L. falcigera are ergatoid and wingless, and males are relatively uncommon. Specimen records from Palau and Madagascar indicate the species nests in rotting logs and cavities both on and above ground, and mostly solitary workers forage on both strata as well. Many collections were made from sifted leaf litter. Kirschenbaum & Grace (2008)report the species fed mainly on live isopods (which is true for many Leptogenys) and also took 25% sucrose solution. Their study demonstrated that L. falcigera is not an aggressive species, and has a strong capacity for surviving encounters with more dominant ants. In Hawaii, the species is thought to exert little impact on native species on account of its small colony sizes and uncommonness in habitats frequented by native invertebrates.

External links

Antweb | Antwiki

Diagnostic description

Diagnosis of worker among Antkey species

Antenna 12-segmented. Eyes medium to large (greater than 6 facets); situated distinctly below midline of head. Frontal lobes present. Clypeus distinctly triangular and projects anteriorly well beyond the base of the mandibles; anterior margin of clypeus not denticulate. Mandibles linear; inserted towards lateral corners of the of the anterior head margin; edentate and lacking apical fork. Hind coxae lacking dorsal spine. Pretarsal claws pectinate. Waist 1-segmented. Petiole upright; conspicuous posterior face; narrowly attached to gaster. Gaster armed with sting. First gastral tergite (abdominal segment 4) lacking deep longitudinal furrows. Distinct constriction between abdominal segments 3+4. Color dull black. 

Among Antkey species, L. falcigera is immediately recognizable by the triangular clypeus and long falcate mandibles. The only other ponerine genera in this class that might be confused with Leptogenys are Anochetus and Odontomachus, both of which also have linear mandibles. However, Leptogenys can be easily distinguished by from these two genera by the mandibles which are inserted laterally (versus medially) into the clypeus, the triangular and anteriorly projecting clypeus, and the pectinate (versus simple) pretarsal claws. Leptogenys maxillosa is a very closely related species that is also a tropical tramp and has been introduced into Cuba and Brazil. Leptogenys falcigera can be separated from L. maxillosa by the petiolar node, which in dorsal view is at least as long as broad and usually distinctly longer than broad (Bolton, 1975).

Look alikes

Leptogenys maxillosa

Distribution

Native range. Afrotropics?

Introduced range. Madagascar, Aldabra Is., Sri Lanka, Hawaiian Islands (Kahoolawe, Kauai, Oahu, Molokai and Maui), Kiribati (Teraina), Palau, Cook Is. (Aitutaki)

Click here for updated occurrence data and map on GBIF.org

Videos of live ants

Leptogenys falcigera, Hawaii, 04-01-2011

Leptogenys falcigera workers on foraging raid, Hawaii, 04-02-2011

Leptogenys falcigera carrying prey, Hawaii, 04-02-2011