Myrmecia banksi

Myrmecia banksi is known only from low elevations along a narrow coastal and sub-coastal strip in New South Wales south from Sydney to Batemans Bay. This species was referred to in previous JACP publications as the "greenhead" form of M. (pilosula), as “M. (pilosula) 2n=10”, or informally as M. banksi.

Distribution
Taylor (2015) - Known from coastal or sub-coastal NSW, from Leumeah, Sydney, south to Catalina, Batemans Bay. All collections are from elevations below 70 meters. Localities most distant from the coast are at Wandandian (ca 5km inland) and Leumeah (ca 24 km). Myrmecia banksi will almost certainly range further north and south, and could occur more widely in the Sydney area where records of Jack-jumpers are currently sparse.

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Nomenclature

 *  banksi. Myrmecia banksi Taylor, 2015: 501 (w.) AUSTRALIA.

Type Material


Forest Road marks the boundary between Currambene State Forest (to the North) and Nowra State Forest. The area is referred to locally as Comberton. Holotype and paratypes in, paratypes or type-compared vouchers in , , , , WAMA, TMHA) and in , , ,.

Worker
General features as illustrated and in key couplets 1, & 3. Myrmecia banksi is distinguished within the pilosula complex by its dense, brassy-green cephalic pubescence. This produces strong greenish-yellow reflections, readily visible in living specimens with hand lens magnification, and encouraged Imai’s field epithet “greenhead”. Anterior femora chocolate brown, each with a reddish-orange apical section up to 1/3 its length, matching the adjacent tibia. Middle tarsi and tibiae reddish-orange, matching those of fore legs. Hind femora and tibiae dark brown, like anterior femora; the tibiae sometimes a little lighter, with their apices and the tarsi progressively lighter in color towards the foot. Myrmecia banksi is otherwise morphologically similar to the eastern species Myrmecia impaternata and the Western Australian M. imaii, which have similar but usually much-less dense brassy cephalic pilosity, and distinctive, very different karyology. The provenance of specimens and their comparison with confidently identified vouchers is important in differentiating these taxa.

(Holotype, smallest paratype, largest paratype (mm): TL = 13.04, 11.81, 13.45; HW = 2.66, 2.26, 2.76; HL = 2.44, 2.48, 2.77; CI = 109, 109, 111; EL =1.02, 0.87, 1.06; OI = 38, 38, 38; SL = 1.98, 1.75, 2.09; SI = 74, 77, 76; PW = 1.72, 1.70, 1.77; WL = 3.86, 3.33, 3.92; PetW = 0.94, 0.77, 1.01; PpetW = 1.50, 1.19, 1.60.

Karyotype


Taylor (2015) - Most examined specimens (sampled from all localities except Catalina and Batemans Bay) had the monomorphic karyotype 2K=6M +2Mc +2A (2n=10) (Imai, Taylor et al., 1994: 147, Fig. 5h). One putative mutant individual from Leumeah (sample HI–AAGH–11) had a complicated translocation producing 2n=9 (Imai, Crozier et al., 1977).

Etymology
Named for Joseph Banks (1743–1820) who with Daniel Solander in 1770 first scientifically collected Australian ants and other insects at Botany Bay, NSW, while exploring ashore from James Cook’s HM Bark Endeavour in habitat similar to that at the M. banksi Type Locality. The Endeavour  landing site is about 100km NNE of the M. banksi South Nowra site.

References based on Global Ant Biodiversity Informatics

 * Imai, H. T.; Taylor, R. W.; Crozier, R. H. 1994. Experimental bases for the minimum interaction theory. I. Chromosome evolution in ants of the Myrmecia pilosula species complex (Hymenoptera: Formicidae: Myrmeciinae). Japanese Journal of Genetics 69:174-175. [1994-04-25] PDF 126063
 * Taylor R. W. 2015. Ants with Attitude: Australian Jack-jumpers of the Myrmecia pilosulaspecies complex, with descriptions of four new species (Hymenoptera: Formicidae: Myrmeciinae). Zootaxa 3911(4): 493-520.