Chelaner bihamatus

Chelaner bihamatum is reasonably common throughout temperate Australia, where it is mostly associated with mallee and harvests mallee seeds (label data). However, the worker from Beonaddy Swamp, near Perth, was found in mixed Eucalyptus woodland. (Heterick 2001)

Identification
Heterick (2001) - A member of the rubriceps group. Although this species resembles Chelaner legulum in gross morphology, the nature of the cuticular sculpture places C. bihamatum near C. longiceps. Some workers, including the holotype, also have vestigial denticles at the propodeal angle.

Heterick (2009) - Chelaner bihamatum and Chelaner legulum are very similar red species. The latter is distinguished chiefly by a darker band on the mesosoma.

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Nomenclature

 *  bihamatum. Monomorium bihamatum Heterick, 2001: 419, figs. 43, 73, 77, 78 (w.) AUSTRALIA.
 * Combination in Chelaner: Sparks et al., 2019: 232.

Worker
Holotypes. HML 2.89; HL 0.97; HW 0.87; Cel 90; SL 0.80, SI 92; PW 0.64. Others. HML 2.44-3.22; HL 0.86-1.05; HW 0.75-0.96; Cei 82-93; SL 0.69-0.82; SI 81-96; PW 0.48-0.69 (30 measured).

As for the worker of Chelaner longiceps, but with the following apomorphies.

Head. Vertex of head capsule slightly concave to planar. Eye large, eye width greater than 1.5x greatest width of antennal scape. Frontal lobes parallel straight. Venter of head capsule with elongate, basket-shaped setae in at least some individuals.

Alitrunk. Promesonotal sculpture present in form of uniform microreticulation with few mesopleural striolae. Mesonotal suture absent. Propodeal processes absent (propodeum smoothly rounded in profile or with slight hump at propodeal angle), or vestigial (propodeum angulate in profile); lobes present as blunt flanges. Propodeal angle absent, or present.

Petiole and postpetiole. Petiolar spiracle lateral and in anterior sector of petiolar node. Petiolar node cuboidal; sculpture present in form of microreticulation, or present; petiolar node rugose. Height ratio of petiole to postpetiole near 1: 1; height-length ratio of postpetiole near 2: 1 to near 4:3. Sculpture present in form of microreticulation. Ventral process absent or vestigial, or present and distinct.

General characters. Colour of head, trunk, and appendages reddish-orange, gaster orange. Worker caste monomorphic

Type Material
Holotype. Worker (top point), Western Australia, Balladonia, 13.i.1970, B. B. Lowery, limestone mallee, 10" rainfall, 6 pm, Chelaner . Paratypes. New South Wales: 5 workers, Condobolin, 11.i.1967, B. B. Lowery, 650 [?ft], common on mallee gums, returning with mallee seeds, nest in sand . South Australia: 3 workers, Streaky Bay, 23.ix.1957, B. B. Lowery, limestone mallee, on mallee gums, Chelaner . Western Australia: I worker with same data as the holotype (ANIC), 2 workers and 1 ergatoid, Esperance district, 4.i.1966, C. Mercovich (BMNH); 6 workers, 38 miles N of Balladonia Hsd. 31°55'S, 127°49'E, 11.xi.1969, R. W. Taylor, Key's field notes, trip 163, stop 19542.1, ANIC ant vial no. 9.207 (ANIC).



Etymology
Latin: “two-hooked”.