Myrmecina australis Wheeler & Wheeler

Shattuck, Steve, 2009, A revision the Australian species of the ant genus Myrmecina (Hymenoptera: Formicidae), Zootaxa 2146, pp. 1-21 : 6-7

Myrmecina australis Wheeler & Wheeler

( Figs 8–11 , 48 )

Myrmecina australis Wheeler & Wheeler, 1973: 34 .

Types. Four syntype larvae from New South Wales, B. B. Lowery (MCZC).

Diagnosis. Basal segment of funiculus shortened and expanded laterally, with strongly convex sides and appearing essentially spherical. The shape of this antennal segment is highly distinctive and will separate this species from all others known from Australia.

Worker description. Antennal scapes smooth or with low ridges. First segment of funiculus expanded laterally and nearly spherical in shape. Sides of head behind compound eyes smooth. Sculpturing on dorsal surface of mesosoma running longitudinally and generally with the central carina (or carinae) running nearly the length (the pronotum not differentiated from the mesonotum). Dorsal and lateral surfaces of mesosoma separated by an indistinct angle or ridge which interrupts or breaks the mesosomal sculpturing. Metanotal spines short. Propodeal spines long. Erect hairs abundant, straight to gently curved. Colour dark brown-black, antennae, mandibles and legs yellow-brown.

Measurements. Worker (n = 8)—CI 98–108; HL 0.70–0.80; HW 0.69–0.83; MTL 0.36–0.43; SI 78–85; SL 0.58–0.69; WL 0.85–1.05.

Additional material examined ( ANIC except where noted). Australian Capital Territory: Mt. Ainslie (Brooks,C.G.); Wombat Creek, 6km NE Piccadilly Circus (Weir,T.A., Lawrence,J. & Johnson). New South Wales: 10.5km W of Gibraltar Range N.P. (HQ) (Monteith,G.B.); 15km E Legume (Greenslade,P.J.M.); 15.5km N Mulwala, Wahgunyah State Forest (Freudenberger,D.) ( TERC); 2 km SSE of Bundanoon (Hill,L.); 20km E Legume (Greenslade,P.J.M.); 2km N Monga (Harvey,M.S.); 2km NW Bomaderry (Moran,R.J.); 5km SW Pigeon House (Hill,L.); Allyn R., 44km NW Dungog (Hill,L.); Barrington Tops Nat. Pk (Ward,P.S.); Barwick Ck. Bog on New England N.P. Road (Hill,L.); Cambewarra Mountain (Taylor,R.W.); Gibraltar Range Nat. Pk (Hill,L.; Monteith,G.B.); Jerrabomberra Hill nr. Queanbeyan (Taylor,R.W. & Weir,T.A.); Kanangra Brook and Rocky Spur, Kanangra-Boyd Nat. Pk (Hill,L.); Killarney Gap, Narrabri (Room,P.M.); Lower Stringybark Creek Reserve (Gush,T.); Moonpar Nat. Forest (Gush,T.); Myall Lakes (Greenslade,P.J.M. & Moulton); Myall Lakes (York,A.); Myall Lakes Nat. Pk (York,A.); Nothofagus Mtn , 12km N Woodenbong (Monteith, Yeates & Cook); Orara East State Forest (Gush,T.); Pt. Lookout, New England N.P. (Taylor,R.W.); Tomalla Tops, Mt. Royal Range (Darlingtons); Upper Hunter Valley (Schnell,M.) ( TERC); Whiporie, 55km S Casino (York,A.). Queensland: Bunya Mountains (Monteith,G.B.); Joalah Nat. Pk, Mt. Tambourine (Woodward,T.E.); Lamington Nat. Pk (Woodward,T.E.) ( ANIC); Lamington Nat. Pk, various sites (Burwell,C.; Burwell,C. & Wright,S.; Monteith,G. & Menendez,R.; Nakamura,A.; Staunton,K.; Thompson,G.; Thompson,G. & Burwell,C.; Wright,S.; Wright,S. & Burwell,C.; Wright,S. & Nakamura,A.) ( QMBA); Mt. Chinghee, 12km SE Rathdowney (Monteith, Yeates & Thompson); Mt. Hobwee area, Lamington Plat. (Woodward,T.E.); slopes below Wilsons Peak (Woodward,T.E.); Tamborine Mt. (Woodward,T.E.).

Comments. This is the southern-most species of Myrmecina found in Australia. It occurs in a range of habitats from dry sclerophyll woodlands through wet sclerophyll, Nothofagus and Dicksonia forests and into rainforest. Most specimens have been found in leaf litter samples or under rocks.

The name australis was first published by Wheeler and Wheeler (1973) when describing larvae received from B. B. Lowery from an unspecified locality in New South Wales. The name was attributed to Forel, indicating that the Wheeler’s did not intend to establish a new species. It was treated as a nomen nudum until it was correctly recognised by Bolton (1995) that the larval description met the requirements of the ICZN to be treated as an available name. Unfortunately it is difficult to determine the identity of this taxon as specieslevel differences among ant larvae are minimal and few species are represented by the larval stage.

The origin of the name seems to lie with Lowery. Lowery labelled a number of his collections as being “ Myrmecina australis Forel ,” this material ranging from northern Queensland to southern New South Wales. It appears that he sent specimens from New South Wales to the Wheeler’s which were labelled as being “ Myrmecina australis Forel. ” They accepted this name without checking its validity, the result being that they inadvertently created a new available name. While we don’t know the exact collection locality for these larvae, the vast majority of Lowery’s collections were from central and southern New South Wales and lie within the range of this taxon and no other. It is therefore highly likely that these larvae belong to this species.

This name could be treated as species inquirenda, arguing that there is no direct evidence to associate it with workers and therefore no positive way to relate it to the worker-based taxonomy developed in this study. And while its identity could be determined with DNA barcoding methods, it seems unlikely that currently available technologies will recover significant intact DNA from 40-year old larvae stored at room temperature. Unfortunately, this course of action would leave this name unplaced within the taxonomy developed here, a less than desirable situation.

To avoid having M. australia unplaced, and based on the high likelihood that it belongs to this taxon, this name is here accepted for this taxon rather than proposing a new name. As long as the taxon concept proposed here is accepted then this nomenclature will remain stable. If, however, this species is found to represent more than one taxon then the status of this name can be re-examined and resolved or it can be treated as species inquirenda and new names proposed for this and any additional taxa discovered.

Figures

FIGURES 8 – 11. Myrmecina australis Wheeler and Wheeler worker. Fig. 8, front of head; Fig. 9, antenna showing spherical first funicular segment; Fig. 10, lateral view of body; Fig. 11, dorsal view of body.

FIGURES 47 – 52. Distribution of material examined during this study. Fig. 47, M. alpina, M. pumila, M. silvalaeva, M. silvampla, M. silvangula, M. silvarugosa and M. silvatransversa; Fig. 48, M. australis; Fig. 49, M. difficulta; Fig. 50, M. eruga (circles) and M. rugosa (square); Fig. 51, M. inaequala; Fig. 52, M. wesselensis.