Anochetus tua

The type specimens were collected from "hill forest."

Identification
Brown (1978) - A. tua takes its name from the Malay word meaning elder or senior, and also meaning darker in color, in reference to its size and hue. Among the larger risii group species with long mandibles, only Anochetus risii and [[Anochetus agilis might be confused with tua, especially A. agilis, with its even more slender head, elongate body, and variable petiolar shape, But the sculptural differences, which are about the same as for the comparison against A. risii, and the much darker color of mature workers, will serve to distinguish A. tua with ease.

Key to the Anochetus Species of Asia, Melanesia and the Pacific Region

Distribution based on Regional Taxon Lists
Indo-Australian Region: Borneo, Malaysia.

Castes
Queens and males of this species are unknown.

Nomenclature

 *  tua. Anochetus tua Brown, 1978c: 580, figs. 1, 29 (w.) WEST MALAYSIA.

Worker
Holotype, worker: TL 8.2, HL 1.77, HW 1.47, ML 1.22, WL 2.54, scape L 1.68, eye L 0.32 mm; CI 83, MI 69.

A moderately larger (longer) relative of Anochetus risii, with the following additional differences from that species:

1. Color much darker: body dark reddish-brown to piceous, appearing black to the naked eye (trunk and petiole lighter reddish-brown in presumably partly teneral paratype examples); posterior and often anterior corners of head reddish; gastric apex, mandibles, antennae and legs predominantly light ferruginous to dull yellow.

2. Sculpture more extensive and coarser. Frontal striation occupies most of the central vertex, and faint traces sometimes even reach the nuchal carina on each side of the midline; «occipital» lobes and sides of head behind eyes smooth and shining. Pronotum completely sculptured and opaque to subopaque, though sculpture may be weak discad, consisting here of fine, indefinite rugulosity with shagreening, mostly inverted U- or V-like in pattern; front of pronotum transversely costulate, the costulae continuing around onto the sides of the pronotum as fine reticulo-striation. Mesonotum irregularly transversely striolate, the sculpture more or less effaced mesad. Mesopleura mainly smooth and shining, with traces of rugulae toward the ends; metapleura shining, with traces of oblique costulation and some shallow punctures. Petiolar node very finely reticulate, but moderately shining. Coxae and gaster smooth and shining. Mandibles, legs and antennae very finely punctulate-shagreened, moderately shining to nearly opaque.

3. Petiolar node thicker, not pointed above, but narrowly rounded, and only slightly laterally compressed toward the apex.

4. Mandibles long and in general shaped like those of risii, but the series of denticles springing from the inner ventral margins sharper and more prominent (fig. 1) as the distinction between dorsal and ventral margins tends to disappear apicad along the shaft. The denticles also tend to be spaced farther apart, and most of them are visible, even in full-face view. Intercalary denticle small, sharp when unworn and situated near the end of the ventral tooth as in risii, but often broken off or worn to a blunt remnant.

The paratypes, aside from color variation already mentioned, vary moderately in dimensions: TL 7.6-8.2, HL 1.73-1.80, HW 1.44-1.48, ML 1.16-1.21, WL 2.42-2.56, scape L 1.65-1.72, eye L 0.31-0.33 mm; CI 82-83, MI 67-68. Variation occurs in size, number and spacing of the denticles on the inner mandibular borders, and details of sculpture on head and trunk vary in minor ways.

Type Material
Holotype and 6 paratype workers (MCZ, ) from Malaysia, Pahang: Fraser's Hill, ca 1300 m, wet hill forest, 16 August 1967, R. H. Crozier, No. CJ 16.

Etymology
A. tua takes its name from the Malay word meaning elder or senior, and also meaning darker in color, in reference to its size and hue.