Monomorium torrens Sparks

Sparks, Kathryn S., Andersen, Alan N. & Austin, Andrew D., 2014, Systematics of the Monomorium rothsteini Forel species complex (Hymenoptera: Formicidae), a problematic ant group in Australia, Zootaxa 3893 (4), pp. 489-529 : 527-528

Monomorium torrens Sparks , NEW SPECIES

( Fig. 8 g–i, 11g)

Holotype worker. South Australia, Flinders Ranges, Dingly Dell , -31.3500, 138.7000, 8 Apr 2008, K. Sparks, KSS4 (deposited in SAM)

Paratypes. South Australia. 19 workers, same data as holotype; 10 workers, Adelaide, -34.9177, 138.6036, 10 Nov 2011, K. Sparks, KSS242 (deposited in SAM).

Diagnosis. A small light to dark brown species with large eyes and a sinuous to almost straight clypeus. The mesonotum is almost entirely smooth and the petiole node is narrow.

Worker measurements (n=9). HW 0.62–0.82, HL 0.70–0.84, EL 0.15–0.18, PMH 0.25–0.29, PH 0.21–0.25, PNH 0.16–0.18, LHW 0.41–0.49, EW 0.10–0.12, PML 0.43–0.51, ML 0.72–0.84, PL 0.31–0.37, PNWdv 0.18–0.21.

Worker Description. Small species with a small, rectangular head; posterior cephalic margin shallowly depressed medially. Anterodorsal margin of the clypeus sinuous to almost straight, frontolateral carinae forming smooth ridges; anteroventral margin without a small median projection, margin appears straight; sculpture on frons limited to a few strigae only present on antennal lobes; coarse lateral cephalic strigae not reach anterior eye margin, a few very fine strigae may reach eye margin. Eyes large, EW> 0.23 x LHW, 13 ommatidia in longest vertical axis, 10 in longest horizontal axis, in full face view situated in from of lateral head margin.

Mesonotum smooth and shining, metanotal groove sculpture extending just into lateral and posterior portions of posterior region. Mesopleuron and lateral surface of propodeum alveolate, strigae extending anteriorly from metapleural gland bulla and almost reaching metanotal groove. Propodeum in lateral view with dorsolateral angles clearly forming an obtuse angle; dorsally with anterior transverse carinae completely absent in a majority of specimens when present very weakly so, transverse and longitudinal strigae absent. Petiole node narrow, less than 2 x eye width when viewed from above; shape in posterior view tapering to a narrow point, in lateral view anterior and posterior faces converging to a narrowly rounded point. Petiole node smooth and shining, some specimens with fine reticulate sculpture along posterior basal margin, postpetiole without sculpture.T1 completely smooth and without sculpture.

Head and mesosoma light to dark brown with a reddish-orange tinge, petiole and postpetiole somewhat darker, legs brown, metasoma dark brown.

Distribution. This species is known from Adelaide and the Flinders Rangers in South Australia.

Etymology. The specific name is a noun in apposition and refers to the river that runs through Adelaide, the type locality.

COI sequences. Genbank accession numbers for this species are KC572924 and KC573001 .

Figures

FIGURE 8. Workers of the M. rothsteini (Forel) species complex in lateral, head and dorsal view of the mesosoma. Fig. 8 a – c: M. tenebrosum, holotype (10 km N Tom Price, WA, KSS 177), d – f: M. topend, holotype (Darwin, NT, TERC 75), g – i: M. torrens, paratype (Flinders Rangers, SA, KSS 4). Scale bars are 0.5 mm for all views.