Polyrhachis pirata

Habitats are very similar to those of Polyrhachis cyaniventris and syntopic occurrence was observed in the Quezon National Park and in an abandoned coconut grove in Northern Samar.. However, based on its infrequent occurrence relative to P. cyaniventris and the habitats where it has been found, P. pirata probably prefers more natural habitats with higher tree coverage and is possibly restricted to lower altitudes. Although the majority of specimens (Zettel collection #165) were collected on the ground, other individual workers were found foraging on leaves and twigs of small trees and bushes. Nesting habits of P. pirata are unknown. (Sorger and Zettel 2009)

Identification
Sorger and Zettel (2009) - Some intraspecific variation has been observed in P. pirata. Compared with specimens from Luzon, the ants from Northern Samar are smaller, appear more gracile, and have a distinctly more bluish shimmer on gaster.


 * Propodeum relatively broader, PPI 152–189. Small species (TL 7.9–9.0–10.1 mm; HW 1.70–2.30 mm) with numerous setae on entire body: vertex with 2–13–20, mesosoma dorsally with 3–36–60, tergite 1 of gaster with 4–25–40 short black setae. Pronotal spines in cross-section flat. Sculpture of integument coarse; microsculpture of head, mesosoma and gaster overlaid with longitudinal striation. Ridge separating dorsal and posterior face of propodeum sinuate, medially not depressed. Head and mesosoma with dark bluish shimmer . . . . . Polyrhachis cyaniventris


 * Propodeum relatively narrower, PPI 114–137. Large species (TL 10.1–10.8–11.5 mm; HW 2.19–2.50 mm) with only few short black setae on entire body: vertex, dorsum of mesosoma and tergite 1 of gaster without setae (rarely with 2 setae on vertex). Pronotal spines in cross-section triangular and massive. Sculpture of integument fine; microsculpture of propodeum overlaid with fine longitudinal striation. Ridge separating dorsal and posterior face of propodeum sinuate, medially slightly depressed. Head and mesosoma with greenish to coppery shimmer . . . . . Polyrhachis pirata

Distribution
Philippines: Central and Southern Luzon, Mindoro and Samar.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Philippines.

Nomenclature

 *  pirata. Polyrhachis (Myrma) pirata Sorger & Zettel, 2009: 33, figs. 7-10, 12 (w.) PHILIPPINES (Luzon I.).

Worker
Holotype: TL 10.8 mm, HW 2.33 mm, HL 2.83 mm, CI 82, SL 3.33 mm, SI 143, PSPD 3.28 mm, PPL 1.34 mm, PPW 1.71 mm, PPI 128, PTW 3.00 mm, MTL 3.66 mm. Paratype workers (n = 10): TL 10.1–10.8–11.5 mm, HW 2.19–2.37–2.50 mm, HL 2.60–2.83–2.98 mm, CI 81–84–86, SL 3.15–3.34–3.50 mm, SI 130–141–146, PSPD 2.90–3.19–3.50 mm, PPL 1.23–1.38–1.49 mm, PPW 1.49–1.75–1.94 mm, PPI 114–127–137, PTW 2.49–2.93–3.23 mm, MTL 3.18–3.47–3.64 mm.

Head and mesosoma with bluish green, in some specimens slightly coppery shimmer; petiole and gaster often appearing darker and more bluish than mesosoma. Antennae and legs (except femora) black.

Head dorsum with some fine rugae between eyes, sides without rugae. Venter without setae. Vertex usually without setae (except in one specimen with two setae). Frons with fine median furrow and 4–7 setae. Genae without setae. Clypeus on disk with 5–7 setae.

Mesosoma dorsally without setae; in addition to microsculpture on disk of pronotum and – more distinct – on propodeum with very fine longitudinal rugae. Pronotal spines long and massive, in cross-section approximately triangular, their bases conspicuously elevated over anterior pronotal disk. Ridge separating dorsal and posterior face of propodeum sinuate, medially slightly depressed. Sides of propodeum dorsal of stigma with strong longitudinal rugae overlaying microsculpture. Femora and tibiae without setae.

Sculpture of gaster with isodiametric reticulum; tergite 1 without setae, tergite 2 usually without setae (except in five specimens with few setae at hind margin), following tergites and all sternites with numerous setae increasing in length towards apex of abdomen.

Type Material
Holotype (worker) Philippines, Luzon Island, Quezon Province, Quezon National Park near Atimonan, dipterocarp forest near Old Zigzag Road. labelled "Philippinen: Luzon, Quezon\ Atimonan, Quezon NP\ Old Zigzag Rd., 24.-30.3.\ 1998, leg. Zettel (#165)". Paratypes: Luzon Isl.: Zambales Prov. [erroneously labelled “Bataan”]: Olongapo, Subic Bay, "Jungle Educational Survival Training" area, 4.XII.1993, leg. H. Zettel (#37h), 1 worker. Quezon Prov.: Atimonan, Quezon National Park, Old Zigzag Road, 24.-30.III.1998, leg. H. Zettel (#165), 31 workers (, CSW, NHMW,, , USC–EC), 16.III.1999, leg. H. Zettel (#202), 2 workers (NHMW). Camarines Norte Prov.: Labo, Tulay na Lupa, Mt. Labo - Mt. Bayabas area, 17.-18.III.2004, leg. H. Zettel & C. V. Pangantihon (#382), 1 worker (CZW). Mindoro Isl.: Occidental Mindoro: [San Jose,] Mangarin, 12.[19?]17, unknown collector, 1 worker (MCZL). Samar Isl.: Northern Samar Prov.: San Joaquin, Lologayan Falls, 4.-6.III.2003, leg. H. Zettel (#345), 1 worker (CZW), 1.- 5.III.2004, leg. H. Zettel (#377), 9 workers (CZW, NHMW, UPLB).

Etymology
Latin for “pirate,” used as a noun in apposition. The name pirata is an homage to the mythic world of ancient pirates. The stoutness, distinct colours and massive spines of this species – in comparison to related species – served as an inspiration for this name.