Chelaner xantheklemma

The known distribution of C. xantheklemma, which is the Clare Valley in eastern South Australia, and north of Kellerberrin in the eastern wheat-belt, Western Australia, is rather peculiar (Heterick 2001).

Identification
Heterick (2001) - A member of the rubriceps group. Chelaner xantheklemma belongs to a small complex of attractive and rare orange or red-and-orange Chelaner. This particular species is a shining orange with scattered foveae over the head and alitrunk, a condition not found in related taxa.

Distribution
Heterick (2009) - Known from the WA goldfields as well as the wheatbelt. It has also been found in the Clare Valley, in SA.

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Nomenclature

 *  xantheklemma. Monomorium xantheklemma Heterick, 2001: 440, figs. 49, 66, 160 (w.m.) AUSTRALIA.
 * Combination in Chelaner: Sparks et al., 2019: 233.

Worker
Holotype. HML 2.05; HL 0.74; HW 0.60; CeI 81; SL 0.54; SI 90; PW 0.47. Others. HML 1.92-2.58; HL 0.69-0.86; HW 0.58-0.77; CeI 83-92; SL 0.48-0.64; SI 82-92; PW 0.40-0.57 (20 measured).

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

Head. Frons of head capsule smooth and shining with scattered foveae and striolae, pilosity combination of incurved decumbent and subdecumbent setulae and erect and suberect setae. Compound eyes elliptical. Anteromedial clypeal margin emarginate, median clypeal carinae produced as pair of bluntly rounded denticles. Frontal lobes parallel straight. Mandibles (viewed from front) triangular and smooth, with piliferous punctures; basal angle indistinct; apical and basal mandibular margins meeting in curve.

Alitrunk. Promesonotal sculpture present in form of scattered foveae and striolae, mainly on the mesopleuron, and mesopleural striae. Mesonotal suture absent. Metanotal groove absent. Dorsal propodeal face gently convex; processes absent (propodeum smoothly rounded in profile or with slight hump at propodeal angle); lobes present and produced apically so as to form acute angled, sharp projections. Propodeal angle absent.

Petiole and postpetiole. Petiolar node cuboidal. Sculpture absent on dorsum, at least: postpetiole smooth and shining. Ventral process absent or vestigial, or present and distinct.

General characters. Colour of head, alitrunk, petiole and postpetiole a shiny, dark reddish orange to tawny yellow (head lighter in colour in some individuals), gaster and appendages tawny yellow. Worker caste monomorphic.

Male
HML 1.99-2.08; HL 0.53-0.63; HW 0.53-0.60; CeI 95-106; SL 0.14-0.17; SI 26-29; PW 0.62-0.72 (3 measured).

As for the male of Chelaner leae, but with the following apomorphies.

Head. Head width-mesoscutal width ratio near I: 1 to near 3:4. Compound eyes protuberant and circular or subcircular, or protuberant and elliptical. Ratio of length of first funicular segment of antenna to length of second funicular segment near 1 :2. Maximum number of mandibular teeth and denticles: five.

Alitrunk. Mesoscutum in profile evenly convex; mesoscutal pilosity consisting of numerous short setae, incurved medially. Parapsidal furrows present and distinct; notauli present.

Wing. Wing veins predominantly depigmented with distal segments reduced to vestigial lines.

Petiole and postpetiole. Ratio of greatest node breadth (viewed from front) to greatest node width (viewed in profile) near 3:4. Sculpture absent on dorsum, at least: postpetiole smooth and shining; ventral process absent or vestigial.

Gaster. Pilosity of first gastral tergite consisting entirely of well-spaced erect and suberect setae.

General characters. Colour amber to brown.

Type Material
Holotype. Worker (top point), South Australia, Sevenhill, 12.ix.1969, B. B. Lowery, 1500 ft, nest under rock in grassy paddock, SA 197, ANIC ants vial 66.66. Paratypes. South Australia: 2 workers, same data as holotype (ANIC); 17 workers and 1 ergatoid, Clare, 3.iii.l950, J. McAreavey, Chelaner ; 3 worker, Sevenhill, 21.ii.1957, B. B. Lowery ; 1 male and 2 workers, Sevenhill, 12.ix.1963, B. B. Lowery, 1500 ft, R F Valley between rocks, ANIC ant vial 66-66 (MCZ); 1 male, 2 workers and 1 ergatoid, Sevenhill, 21.ii.1957, B. B. Lowery, 1400 ft, under rock on bare ridge top (ANIC).



Etymology
Greek: “orange + peel”.

References based on Global Ant Biodiversity Informatics

 * Heterick B. E. 2001. Revision of the Australian ants of the genus Monomorium (Hymenoptera: Formicidae). Invertebrate Taxonomy 15: 353-459.
 * Heterick B. E. 2009. A guide to the ants of south-western Australia. Records of the Western Australian Museum Supplement 76: 1-206.