Anochetus princeps

Collected from moist forests, nests have been found in a clay bank and a rotting log.

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.

Zettel (2012) - Philippines: Anochetus princeps is unique among all Philippine Anochetus species by the structure of the mandible as described in the key and illustrated in Figure 1. It belongs to the A. rugosus group (Brown 1978).

Anochetus princeps was described from Java, as well as its synonyms A. jacobsoni and A. serratus. Other synonyms, A. princeps var. laeta, and A. jacobsoni var. taipingensis are from Sumatra and West Malaysia, respectively. Brown (1978) presented the first record of A. princeps from the Philippines: Mount Makiling, Laguna Province, Luzon Island. I have examined one worker from the same mountain. As already noted by Brown (1964), some allopatric populations of A. princeps may turn out to be biological species. Compared to specimens from West Malaysia (CZW, NHMW), the Luzon worker has a more strongly elevated anterior rim of the mesonotum, but otherwise it agrees very well, despite its isolated record. In contrast, specimens from Myanmar and Thailand (CZW, NHMW) may belong to an undescribed species, because they differ considerably in pronotum sculpture and head shape.

Satria et al. (2017) – 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, Philippines. Oriental Region: Thailand, Vietnam.

Nomenclature

 *  princeps. Anochetus princeps Emery, 1884a: 379 (diagnosis in key) (w.) INDONESIA (Java). Brown, 1978c: 577 (m.); Wheeler, G.C. & Wheeler, J. 1976a: 61 (l.). Senior synonym of jacobsoni Forel, laeta, serratus, taipingensis: Brown, 1964d: 213.
 * laeta. Anochetus princeps var. laeta Forel, 1910a: 27 (w.) INDONESIA (Sumatra). Junior synonym of princeps: Brown, 1964d: 213.
 * jacobsoni. Anochetus jacobsoni Forel, 1911b: 193 (w.) INDONESIA (Java). Forel, 1913k: 18 (q.). Junior synonym of princeps: Brown, 1964d: 213.
 * taipingensis. Anochetus jacobsoni var. taipingensis Forel, 1913k: 18 (w.m.) WEST MALAYSIA. Junior synonym of princeps: Brown, 1964d: 213.
 * serratus. Anochetus serratus Stitz, 1925: 113 (w.) INDONESIA (Java). Junior synonym of princeps: Brown, 1964d: 213.

Male
Satria et al. (2017) - Description of male genitalia and associated sclerites. Abdominal tergum VIII without a median spine. Abdominal sternum IX (subgenital plate) longer than broad, triangular, tapering toward subrectangular apex, without posterolateral corners. Dorsal outline of paramere in lateral view weakly convex. Distiventral part of valviceps forming an acute, pointed and slightly downcurved projection which is much longer than broad; ventral margin to the apex of projection weakly concave, with 13−14 denticles; dorsodistal margin to the apex very weakly sinuate, with ca. 10 denticles.