Chelaner elegantulus

Monomorium elegantulum has the widest distribution of any member of the falcatum-group, and can be found throughout the drier woodland areas of temperate Australia. (Heterick 2001)

Identification
Heterick (2001) - A member of the falcatum group. This species resembles Monomorium falcatum in many morphological aspects, but is distinguished from that species by its much smaller size. Monomorium elegantulum may also be distinguished from the similar-sized Monomorium decuria by the possession of 12-segmented antennae.

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Nomenclature

 *  elegantulum. Monomorium elegantulum Heterick, 2001: 380, figs. 24, 57 (w.) AUSTRALIA.

Worker
Holotype. HML 1.49; HL 0.62; HW 0.57; Cel 93; SL 0.32; SI 56; PW 0.34. Other. HML 1.51-1.81; HL 0.61-0.72; HW 0.59-0.74; Cei 95-104; SL 0.38-0.44; SI 59-72; PW 0.32-0.42 (18 measured).

As for the worker of Monomorium falcatum, but with the following apomorphies.

Head. Vertex of head capsule planar; frons densely foveate and microreticulate with combination of appressed setulae and erect and suberect setae. (Viewed from front) compound eyes set at midpoint of each side of head capsule. Longest lateral anterior clypeal setae long, extending beyond dorsal margin of closed mandibles. Posteromedial clypeal margin level with posterior surface of antennal fossae. Anterior tentorial pits equidistant between mandibular insertions and antennal fossae. Maximum number of mandibular teeth and denticles: four; apical and basal mandibular margins meeting in tooth or denticle.

Alitrunk. Promesonotum with uniform microreticulation and dorsal foveae; dorsal promesonotal face convex anteriad, otherwise flattened; erect and suberect promesonotal setae >5; setulae appressed. Mesonotal suture absent. Metanotal groove absent. Propodeal angle absent; length ratio of dorsal face to declivitous face near 2: 1. Propodeal setulae appressed.

Petiole and postpetiole. Petiolar node tumular and inclined posteriad; Ratio of greatest node breadth (viewed from front) to greatest node width (viewed in profile) near 4:3 to near 1:1. Anteroventral process always present as pronounced spur. Ventral lobe present in some individuals.

General characters. Colour light orange. Worker caste monomorphic.

Type Material
Holotype. Worker, Western Australia, Mukinbudin, 25.i.1988, M. Jacobs, soil, native veg., cara. park near town, 374/6MonBH48. Paratypes. New South Wales: 13 workers, Nyngan, 10.x.1946, J. Armstrong, Chelaner 12 seg. antennae det. R. W. Taylor 1975 (ANIC); 6 + 10 (1 head missing) workers, Bogan R., J. Armstrong, Chelaner 12 seg. antennae det. RWT. [R. W. Taylor] 1975. ( and ).



Etymology
Latin: “having a very fine appearance”.