Anochetus rugosus

Identification
A member of the rugosa group. Brown (1978) defined the group: Large to medium-sized forms with single, serially dentate inner margins; mesonotal disc with a raised anterior rim; petiole bluntly pointed or narrowly rounded at apex. Male (of princeps) without pygidial spine.

Satria et al. (2017) – The species of the rugosus group differ by the following characters: Anochetus mixtus - Dorsum of head in full-face view largely smooth and shiny, but frons distinctly striate obliquely and longitudinally; mesopleuron smooth and shiny; petiolar node with its basal half weakly striate. Anochetus muzziolii - Pronotal disc smooth and shiny; mandible short (MdI < 60). Anochetus princeps - Pronotal disc smooth and shiny; mesosoma relatively slender; petiole in lateral view with a relatively long anterior peduncle. Anochetus rugosus - Head in full-face view largely striated; lateral face of head partly striated; ventral face of head smooth and shiny; mesosoma relatively short and stout; petiolar node in lateral view with anterior face sinuate and posterior face weakly convex; anterior third of mesopleuron finely sculptured; propodeum coarsely rugose; petiolar node largely coarsely rugose.

Species discrimination based on male genitalia and associated sclerites (no males known for A. muzziolii). Anochetus mixtus is easily distinguished from the other species in the Anochetus rugosus group by the following characters: abdominal sternum IX much longer than broad with obtuse posterolateral corners (in A. princeps much longer than broad, without posterolateral corners; in A. rugosus slightly longer than broad, without posterolateral corners); dorsal outline of paramere weakly convex (in A. rugosus straight, gradually sloping downward to angulate distidorsal part); distiventral part of valviceps produced but shorter than broad, truncate distally (in A. princeps forming an acute, pointed and slightly downcurved projection which is much longer than broad; in A. rugosus forming a subrectangular lobe which is longer than broad); valviceps with 23−24 denticles on the ventral margin (in A. princeps with 13−14 denticles on the ventral margin, and with ca. 10 denticles on the dorsodistal margin; in A. rugosus strongly concave with 19 denticles on the ventral margin, and 9 denticles on the distal margin of the lobe). See figures in male caste section below.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Borneo, Indonesia, Malaysia, Singapore. Oriental Region: Thailand.

Nomenclature

 *  rugosus. Odontomachus rugosus Smith, F. 1857a: 65 (w.) SINGAPORE. Wheeler,G.C. & Wheeler, J. 1976: 61 (l.). Combination in Anochetus: Emery, 1911d: 109. Senior synonym of beccarii: Brown, 1964d: 214; of ineditus, menozzii: Brown, 1978c: 558. See also: Brown, 1978c: 575.
 * beccarii. Anochetus beccarii Emery, 1884a: 379 (diagnosis in key) (w.) INDONESIA (Sumatra). Junior synonym of rugosus: Brown, 1964d: 214.
 * jacobsoni. Anochetus jacobsoni Menozzi, 1939b: 178, fig. 3 (w.) INDONESIA (Sumatra). [Junior primary homonym of jacobsoni Forel, above.] First replacement name: menozzii Donisthorpe, 1941k: 237. Second (unnecessary) replacement name: ineditus Baroni Urbani, 1971b: 360.
 * menozzii. Anochetus menozzii Donisthorpe, 1941k: 237. Replacement name for jacobsoni Menozzi, 1939b: 178. [Junior primary homonym of jacobsoni Forel, 1911b: 193.] Junior synonym of rugosus: Brown, 1978c: 558.

Male
Satria et al. (2017) – Description of male genitalia and associated sclerites. Abdominal tergum VIII without a median spine. Abdominal sternum IX (subgenital plate) slightly longer than broad, triangular, tapering toward subrectangular apex, without posterolateral corners. Dorsal outline of paramere straight, gradually sloping downward to angulate distidorsal part. Distiventral part of valviceps forming a subrectangular lobe which is longer than broad. Ventral margin of valviceps to the anterodistal corner of the lobe strongly concave, with 19 denticles; distal margin of the lobe very short and straight, with 9 denticles. Dorsodistal margin of valviceps weakly sinuate, without denticles.

Type Material
Odontomachus rugosus

The specimen labelled as type by Donisthorpe in is not type-material. Its pin bears two locality labels, one of which is “SAR” (= Sarawak), and the other “Gilolo” (= Halmahera). The type-locality given by Smith (1857a: 65) is Singapore. This is the only Smith coll. specimen of rugosus detected in or. Possibility that the labels have been switched at some date after 1857?