Austroponera castanea

Members of the melanaria group in Australia and Melanesia tend to inhabit mostly the moist, shady forests, but M. castanea shows much wider ecological tolerance in New Zealand, where nests are made not only in the shady forest in rotten wood and leaf litter, but also under stones in open pastures, and even in the soil of vegetable gardens in the cities. Judging from the structure of the workers and females, and from the habits of the melanaria group forms that Wilson and I have seen in the field, I should think that M. castanea is a fast·moving and rather timid ant, though with a respectable sting. The colonies are small to medium in size. Males have been taken abroad in the Auckland district in January and March. (Brown 1958)

Identification
This species shows considerable variation across its range (but see Austroponera castaneicolor).

Distribution
M. castanea is a widespread and common species in the North Island and also is found around Nelson, at the northern tip of the South Island.

Distribution based on Regional Taxon Lists
Australasian Region: New Zealand.

Nomenclature

 *  castanea. Ponera castanea Mayr, 1865: 69 (w.) NEW ZEALAND. Combination in Euponera (Mesoponera): Emery, 1901a: 46; in Mesoponera: Brown, 1958h: 20; in Pachycondyla: Brown, in Bolton, 1995b: 303; in Austroponera: Schmidt & Shattuck, 2014: 182. Senior synonym of striata: Brown, 1958h: 20.
 * striata. Euponera (Mesoponera) castanea var. striata Stitz, 1911a: 356 (w.) NEW ZEALAND. Junior synonym of castanea: Brown, 1958h: 20.

Worker
Brown (1958) - Total outstretched length about 5.5 to 7 mm., with occasional specimens exceeding these limits. Color varying from yellowish (teneral) to dark red or dark brown. The form of the body as seen from the side is shown in Figure 1. The form of the alitrunk varies slightly. and also the shape of the node. The clypeus has a median carina, usually projecting Slightly beyond the anterior c1ypeal border, but this point difficult to see when mandibles are closed. Mandibles with the blades relatively more elongate and with more teeth than in Ponera or Brachyponera. The maxillary palpi in the few workers examined all had 4 segments, the labial palpi, 3. In the females seen, the maxillary palpi always had 4 segments, while the labials had either 3 or 2. The numbers in the male are 6 and 4, respectively. Female a little larger than the worker, with ocelli and flight sclerites of the alitrunk developed, and the compound eyes much larger. The worker and female are distinguished from the related species of the Indo-Australian melanaria group in having the head shorter, in having fairly abundant and generally distributed erect pilosity, and in the thicker, apically rounded petiolar node.

Male
Brown (1958) - About as long as the smallest workers, but very slender, with small, rounded head, blackish in color. Antennae with short scape, so that they are very slender and evenly curved, at least in death, without elbowing.