In Australia, P. andromache is restricted to the lowland rainforests of Cape York Peninsula north of the 14° parallel where it is relatively common. It is characterised by its abundant, distinctly golden or silvery pubescence and yellow or orange-coloured appendages. Polyrhachis andromache builds nests of silk and vegetation debris in various tree cavities, but also within the hollow internodes of standing bamboo (Kohout 1988b, 1989, 1999; Robson & Kohout 2007) (from Kohout, 2012).
Kohout (1988) - Polyrhachis ithona is easily separable in having numerous short hairs projecting from the sides of the head behind the eyes. Such hairs are never present in P. andromache. The head of P. ithona is much broader behind than in front and the antennal scapes relatively short (SI < 140) compared to those of P. andromache (SI > 145). P. andromache is also more slender and delicate than ithona, which is a relatively large and stoutly built species.
Keys including this Species
Distribution based on Regional Taxon Lists
The known distribution is from Moluccas to New Guinea and northern Australia, where the species has been recorded from Torres Strait Islands and Cape York Peninsula as far south as Iron Range. (Kohout 1989)
Distribution based on AntMaps
Distribution based on AntWeb specimens
Check data from AntWeb
Males and immature stages are present in the ANIC and RJK spirit collections.
The following information is derived from Barry Bolton's New General Catalogue, a catalogue of the world's ants.
- hector. Polyrhachis hector Smith, F. 1859a: 142 (w.) INDONESIA (Aru I.). [Junior primary homonym of hector Smith, above.] Replacement name: andromache Roger, 1863b: 8.
- chaonia. Polyrhachis chaonia Smith, F. 1861b: 42, pl. 1, fig. 18 (q.) INDONESIA (Halmahera I.). Combination in P. (Myrma): Emery, 1925b: 200. Junior synonym of ithona: Bolton, 1974b: 177; of andromache: Dorow, 1995: 31.
- andromache. Polyrhachis andromache Roger, 1863b: 8. Replacement name for hector Smith, F. 1859a: 142. [Junior primary homonym of hector Smith, F. 1857a: 62.] Donisthorpe, 1949g: 420 (m.); Kohout, 1989: 510 (w.q.). Combination in P. (Myrma): Forel, 1915b: 110. Subspecies of relucens: Emery, 1897d: 579; Forel, 1901b: 28. Senior synonym of connectens: Emery, 1897d: 580. Junior synonym of ithona: Bolton, 1974b: 177. Revived from synonymy, revived status as species and senior synonym of australiae: Kohout, 1988c: 430. Senior synonym of semirufipes and material of the unavailable name harmsi referred here: Kohout, 1998: 521.
- australiae. Polyrhachis connectens var. australiae Emery, 1887a: 231 (w.) AUSTRALIA. Combination in P. (Myrma): Emery, 1925b: 202. Junior synonym of relucens: Emery, 1893e: 228; of andromache: Emery, 1896d: 379. Revived from synonymy as subspecies of relucens: Taylor & Brown, D.R. 1985: 140. Junior synonym of andromache: Kohout, 1988c: 431.
- connectens. Polyrhachis connectens Emery, 1887a: 230, pl. 4, fig. 19 (w.) NEW GUINEA. Subspecies of relucens: Dalla Torre, 1893: 267; Emery, 1896d: 379. Junior synonym of andromache: Emery, 1897d: 580.
- semirufipes. Polyrhachis (Myrma) proxima var. semirufipes Donisthorpe, 1943d: 469 (w.) NEW GUINEA. Junior synonym of andromache: Kohout, 1998: 521.
Polyrhachis hector type material.
Holotype worker from Aru Island, Indonesia (A.R.Wallace) (Oxford University Museum of Natural History) (examined by Kohout, 2012).
Polyrhachis connectens australiae type material.
Syntype workers and queen from Somerset, Cape York, Australia (L.M. D’Albertis) (Museo Civico di Storia Naturale, Genoa) (examined by Kohout, 2012).
- Polyrhachis connectens australiae Emery, 1887: Syntype, worker(s), queen(s), Somerset, Queensland, Australia, Museo Civico di Storia Naturale, Genoa.
- Polyrhachis hector Smith, 1859: Holotype, worker, Aru, Indonesia, Oxford University Museum of Natural History.
Holotype queen in Oxford University Museum of Natural History. Labelled “Gil.” (= Gilolo (Halmahera)) and with a Donisthorpe type-label.
Holotype worker in Oxford University Museum of Natural History. Labelled “Aroo” (= Aru I., New Guinea) and with a Donisthorpe type-label. Below this is a Donisthorpe det. label “relucens subsp. andromache.”
Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.
Kohout (1989) - Dimensions: TL 7.58-9.73; HL 2.12-2.50; HW 1.65-2.01; CI 78-82; SL 2.56-2.97; SI 145-158; PW l.18-1.51; MTL 2.59-3.07 (30 measured).
Mandibles with 5 teeth. Clypeus in profile almost straight; the anterior margin entire. Sides of head in front of eyes shallowly concave, slightly converging anteriorly; widely rounded behind. Eyes convex, in full face view usually only marginally breaking the outline of the head. Frontal carinae sharply raised. Pronotal dorsum with a pair of long, divergent, somewhat flattened spines; their dorsolateral borders continuous with the pronotal margins. Mesonotal dorsum transversely convex. wider than pronotum at the base, the lateral margins converging strongly posteriorly. Propodeal dorsum almost flat, with margins converging into weakly upturned posterior angles. Petiole with two posterodorsally directed spines and, between them, a more or less distinct, small intercalary tooth. A somewhat flattened, deeply emarginated tooth, is situated laterally below the level of the base of each spine. First gastral tergite shallowly concave basally.
Mandibles finely, regularly striate, with numerous piliferous pits. Head and lateral branches of mesosoma finely reticulate; dorsum of mesosoma, petiole and the gaster shagreened.
A few long, erect, somewhat undulated hairs scattered on dorsum of the head and mesosoma. Such hairs are relatively more abundant and posteriorly directed on the gaster. Bright golden or, less frequently, silvery pubescence more or less obscuring the underlying sculpturation. And abundant all over the body, except on the mandibles and tips of the spines.
Generally black, with coxae, femora, tibia and proximal and distal ends of the antennal scapes yellow or light yellowish-brown.
Kohout (1989) - Dimensions: TL 9.98-11.59; HL 2.50-2.74; HW 2.01-2.21; CI 79-82; SL 2.87-3.12; SI 136-143; PW 2.03-2.22; MTL 3.06-3.22 (7 measured).
Female almost identical to worker apart from its larger size and the characters identifying full sexuality. The pronotal spines are shorter and downturned, and the dorsum of petiole armed with 3 distinct teeth.
- Bolton, B. 1974b . New synonymy and a new name in the ant genus Polyrhachis F. Smith (Hym., Formicidae). Entomol. Mon. Mag. 109: 172-180 (page 177, Junior syinonym of ithona)
- Donisthorpe, H. 1949h. A seventh instalment of the Ross Collection of ants from New Guinea. Ann. Mag. Nat. Hist. 12(2): 401-422 (page 420, male described)
- Emery, C. 1897e. Viaggio di Lamberto Loria nella Papuasia orientale. XVIII. Formiche raccolte nella Nuova Guinea dal Dott. Lamberto Loria. [concl.]. Ann. Mus. Civ. Stor. Nat. 38[=(2(18): 577-594 (page 579, Subspecies/race of relucens)
- Emery, C. 1897e. Viaggio di Lamberto Loria nella Papuasia orientale. XVIII. Formiche raccolte nella Nuova Guinea dal Dott. Lamberto Loria. [concl.]. Ann. Mus. Civ. Stor. Nat. 38[=(2(18): 577-594 (page 579, Senior synonym of connectens)
- Forel, A. 1901b. Critique des expériences faites dès 1887 avec quelques nouvelles expériences. Troisième partie (1901). Riv. Biol. Gen. 3: 7-62 (page 28, Subspecies/race of relucens)
- Forel, A. 1915b. Results of Dr. E. Mjöbergs Swedish Scientific Expeditions to Australia 1910-13. 2. Ameisen. Ark. Zool. 9(1 16: 1-119 (page 110, Combination in P. (Myrma))
- Kohout, R. J. 1988c. Nomenclatural changes and new Australian records in the ant genus Polyrhachis Fr. Smith (Hymenoptera: Formicidae: Formicinae). Mem. Qld. Mus. 25: 429-438 (page 430, Revived from synonymy, revived status as species, and senior synonym of australiae:)
- Kohout, R. J. 1989. The Australian ants of the Polyrhachis relucens species-group (Hymenoptera: Formicidae: Formicinae). Mem. Qld. Mus. 27: 509-516 (page 510, worker, queen described)
- Kohout, R. J. 1998. New synonyms and nomenclatural changes in the ant genus Polyrhachis Fr. Smith (Hymenoptera: Formicidae: Formicinae). Mem. Qld. Mus. 42: 505-531 (page 521, Senior synonym of semirufipes and material of the unavailable name harmsi referred here)
- Kohout, R.J. 2012. A review of the Australian Polyrhachis ants of the subgenera Myrma Billberg, Myrmatopa Forel, Myrmothrinax Forel and Polyrhachis Fr. Smith (Hymenoptera: Formicidae: Formicinae). Memoirs of the Queensland Museum – Nature 56(1): 25-59.
- Roger, J. 1863b. Verzeichniss der Formiciden-Gattungen und Arten. Berl. Entomol. Z. 7(B Beilage: 1-65 (page 8, Replacement name for hector)
- Smith, F. 1857a. Catalogue of the hymenopterous insects collected at Sarawak, Borneo; Mount Ophir, Malacca; and at Singapore, by A. R. Wallace. [part]. J. Proc. Linn. Soc. Lond. Zool. 2: 42-88 (page 62, pimary homonym)
- Smith, F. 1859c. Catalogue of hymenopterous insects in the collection of the British Museum. Part VII. Dorylidae and Thynnidae. London: British Museum, 76 pp. (page 62, [Junior primary homonym of hector Smith, F. 1857a: 62.])