Poneracantha bispinosa

Along with Gnamptogenys perspicax,  Gnamptogenys bispinosa represents a highly specialized form in one lineage of millipede hunters. (Lattke 1995)

Identification
Eyes subglobulose, scapes long and surpassing vertexal margin; mandibles edentate. Promesonotal suture breaks sculpture dorsally but not laterally; mesometanotal suture deep and broad. Head, mesosoma and postpetiole rugose; ferruginous. (Lattke 1995)

Distribution based on Regional Taxon Lists
Neotropical Region: Colombia, Costa Rica, Panama.

Biology
Lattke (1995) - This wet forest species is a millipede specialist. J. Longino (pers. comm.) observed the following two raids from the same colony, both at 11:00 AM: "A column of 20 workers was moving along a liana on the forest floor. They left the liana and moved very slowly across the leaf litter, frequently bunching up. They all went under a leaf and then agitated ants could be seen coming out from under the lea f, 2 or 3 ants at a time, cleaning their antennae and mandibles. I removed the leaf to find the ants attacking a millipede. Some were stinging and some were pulling on the legs. The distance from the first sighting to the prey was 6 m. I followed a returning worker as far as I could into a tree fall tangle, 10 m from prey." The second attack involved 46 workers tackling a 6 cm long millipede within a rotten log. Once the millipede was subdued they carried it back to the nest.

Two millipedes taken from the nest by Longino were determined by R.L. Hoffman as Trichomorpha sp. (Polydesmida: Chelodesmidae), and Epinannolene sp. (Spirostreptida: Epinannolenidae).

Morphology
The anterior clypeal setae are more developed than in any other of the rastrata group species and an interesting autapomorphy is a brief anteromedian longitudinal sulcus on the clypeus. (Lattke 1995)

Nomenclature

 *  bispinosa. Ectatomma (Holcoponera) bispinosum Emery, 1890b: 40 (w.) COSTA RICA. [Also described as new by Emery, 1894k: 47.] Wheeler, G.C. & Wheeler, J. 1952a: 133 (l.). Combination in E. (Ectatomma): Emery, 1896g: 37; in E. (Poneracantha): Emery, 1897d: 547; in Gnamptogenys: Brown, 1958g: 227. See also: Brown, 1958g: 301; Lattke, 1995: 158.