Anochetus graeffei

Nests are generally under rocks or occasionally other objects on the ground but Anochetus graeffei is also known to nest directly in soil without covering, in termite nests and in rotten wood. This is one of the most widely distributed species within the genus, occurring from southern India east through SE Asia to Australia and onwards to the Cook Islands; it is also one of the most morphologically variable.

Identification
Shattuck and Slipinska (2012) - Australia: Eyes very small (EL < 0.16mm); front of head with sculpturing extending to the posterior margin; pronotum with coarse and heavy striate-rugose sculpture; body very hairy, with abundant erect hairs on all surfaces. This is the most heavily sculptured species of Anochetus within Australia, approached only by Anochetus victoriae. These two taxa can be separated by the rugulose rather than striate sculpturing on the dorsum of the pronotum and the smaller eye (eye length < 0.16mm vs. > 0.22mm) in A. graeffei.

Zettel (2012) - Philippines: workers and gyne examined are peculiar by some fine striation in addition to the coarse puncturation of gaster tergite 1, a character that is also present in a sample from Sarawak, Borneo (NHMW). A distinct indention of the apex of the petiolar node is present in the workers from Laguna and in the gyne from Palawan, but absent in the Masbate worker.

Chen et al. (2019) - China: The species is similar to Anochetus lanyuensis, Anochetus validus, and Anochetus victoriae, but well separated from them by the following characters: dorsal outline of pronotum gradually sloping anteriorly, not forming a straight outline with mesonotum and propodeum; pronotal disc with dense inverted U-shaped rugae; scapes just reaching to posterior corner of head.

Distribution
Southern India east through SE Asia to Australia and onwards to the Cook Islands.

Within Australia this is one of the most widely distributed and commonly encountered species, occurring from the Kimberleys eastward through the Top End and then throughout eastern Queensland south into north-eastern New South Wales. It is most commonly encountered in rainforest habitats but also extends into dry sclerophyll woodlands. It has only rarely been found outside forested sites. (Shattuck and Slipinska 2012)

Distribution based on Regional Taxon Lists
Australasian Region: Australia, New Caledonia. Indo-Australian Region: Borneo, Cook Islands, Fiji, Indonesia, Kiribati, Krakatau Islands, Malaysia , Marshall Islands, Micronesia (Federated States of), New Guinea, Northern Mariana Islands, Palau, Philippines , Samoa , Solomon Islands, Tokelau, Tonga, Wallis and Futuna Islands. Oriental Region: Bangladesh, Cambodia, India, Laos, Myanmar , Nicobar Island, Thailand, Vietnam. Palaearctic Region: China.

Nomenclature

 *  graeffei. Anochetus graeffei Mayr, 1870b: 961 (w.) SAMOA. Mayr, 1876: 86 (q.); Wheeler, G.C. & Wheeler, J. 1971b: 1212 (l.); Imai, Brown, et al. 1984: 5 (k.). Senior synonym of amati, minutus, oceanicus, punctiventris: Wilson, 1959a: 507; of rudis, taylori: Brown, 1978c: 557 (see also p. 586). See also: Shattuck & Slipinska, 2012: 11.
 * punctiventris. Anochetus punctiventris Mayr, 1879: 659 (w.) INDIA. Forel, 1900c: 63 (q.). Junior synonym of graeffei: Wilson, 1959a: 507.
 * rudis. Anochetus rudis Emery, 1889b: 499 (w.) MYANMAR. Subspecies of punctiventris: Forel, 1900c: 60; Emery, 1911d: 109. Revived status as species: Bingham, 1903: 41. Junior synonym of graeffei: Brown, 1978c: 577.
 * oceanicus. Anochetus punctiventris subsp. oceanicus  Emery, 1897c: 597 (w.) NEW GUINEA. Emery, 1914f: 400 (q.m.). Junior synonym of graeffei: Wilson, 1959a: 507.
 * taylori. Anochetus punctiventris r. taylori Forel, 1900c: 63 (w.) INDIA. Raised to species: Bingham, 1903: 43. Junior synonym of graeffei: Brown, 1978c: 557.
 * amati. Anochetus amati Karavaiev, 1925c: 285, fig. 8 (q.) INDONESIA (Aru I.). Junior synonym of graeffei: Wilson, 1959a: 507.
 * minutus. Anochetus minutus Karavaiev, 1925c: 288, fig. 10 (w.q.) WEST MALAYSIA. Junior synonym of graeffei: Wilson, 1959a: 507.

Taxonomic Notes
Shattuck and Slipinska (2012) - This is one of the most widely distributed species within the genus, occurring from southern India east through SE Asia to Australia and onwards to the Cook Islands; it is also one of the most morphologically variable (Brown, 1978). The concept of this species adopted by Shattuck & Slipinska (2012) follows that proposed by Brown (1978). While a detailed study of the entire species, including examination of specimens from throughout its broad range, was outside the scope of their study, a preliminary analysis does not suggest obvious subdivisions and Brown's interpretation of the variation he noted as intra- rather than interspecific is accepted. Additionally, an examination of specimens from inland north Queensland which Brown flagged as possibly belonging to a separate but closely related species could not be confirmed and material from this region is treated as belong to A. graeffei.

Zettel (2012) - The taxonomy and synonymy of A. graeffei was treated by WILSON (1959) and BROWN (1978). Following these authors, A. graeffei is very widely distributed from India to Australia and a most polymorphic species. According to BROWN (1978) this decision is not final: “The bounds of graeffei variation, and whether or not the species divides into sibling species, are ripe subjects for future gammataxonomic studies.” Variation concerns size, colour, and sculpture (most notably on head, pronotum and gaster tergite 1).

A hitherto undescribed, but important peculiarity of both A. graeffei s.l. and A. ruginotus are short setae on the compound eyes; it is undescribed whether or not this character is also present in other species of Brown's A. graeffei group. Less obvious, shorter setae have been also observed in a few species of the A. risii group.

Description
Shattuck and Slipinska (2012) - Worker description. Body smaller (head length < 1.14mm), with abundant erect or semierect hairs. Eyes very small (eye length < 0.16mm). Sculpturing on front of head nearly reaching posterior margin and extending slightly laterally. Dorsum of head with abundant semierect hairs as well as a few erect hairs. Scapes not reaching posterolateral corners ('lobes') of head; with abundant, slightly elevated pubescence and a limited number of erect hairs. Pronotum with characteristic punctate, irregularly rugose sculpture. Anterior section of pronotum with transverse wrinkles and ridges. Mesonotum and dorsum of propodeum with coarse striate-rugose sculpture. Dorsum of propodeum rounded laterally, with slightly rounded angle and numerous erect hairs. Metapleuron smooth and shining anteriorly. In anterior view petiolar node with apex rounded. Erect hairs on hind tibiae short and scattered. Colour from yellowbrown to brown, head from yellow to yellow-brown, antennae, mandibles and legs yellow or yellow-brown.

Measurements. Worker (n = 5): CI 92–93; EI 14–15; EL 0.13–0.15; HL 0.95–1.13; HW 0.89–1.06; HFL 0.77–0.89; ML 1.09–1.30; MandL 0.52–0.59; MTL 0.54–0.66; PronI 59–63; PronW 0.52–0.64; SL 0.76–0.87; SI 83–89.