Common in Perth Gardens. Melophorus Wheeleri Forel Is
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A Guide to the Ants of South-western Australia 101 common in Perth gardens. Melophorus wheeleri JDM 176 has distinct, superficial microsculpture, Forel is found from the Pilbara down to the gold most notably on the lower mesopleuron (i.e. the fields, and into the wheatbelt at least as far west as katepisternum) and propodeum. In lighter-coloured Kellerberrin. Workers from Jiggalong Station have forms of Melophorus sp. JDM 176 the orange colour been collected in the process of carrying seeds of is of a slightly deeper hue than in Melophorus ANIC Lepidium phlebopetalum (Brassicaceae). Two minor sp. 3, and this colour form is mostly found in the workers collected near Yalgoo, just outside of the drier wheatbelt and mallee country north-east, east SWBP, are aberrant in that they have scattered erect and south-east of Perth. Brown and reddish-brown setae on the dorsum of the mesosoma (otherwise morphs of Melophorus sp. JDM 176 are abundant in lacking in minor workers of M. wheeleri I have seen), the northern sandplains. The major worker of the and one has six teeth on one of the mandibles, two species can be distinguished by the type of rather than the customary seven or more. These pilosity on its pronotum: in Melophorus sp. ANIC 3 may represent another species in the M. wheeleri the standing setae are fine and longer than the eye complex, as other M. wheeleri minor workers in width, while the setae in Melophorus sp. JDM 176 the Curtin Ant Collection are very uniform in are shorter than the eye width, and stout. The above appearance. Melophorus wheeleri complex sp. JDM three taxa constitute the bulk of the small to minute 1077 is known from the far east and north-east Melophorus pitfall-trapped, mainly in the form of of the SWBP. The main stronghold of this species minor workers, in Curtin research projects in both appears to be the Eremaean zone. dry and wetter areas of the SWBP. The Melophorus bruneus complex falls within the In many parts of the state, minuscule minor turneri group, and shares a common mandibular workers with a morphology resembling that of conformation. As with many M. turneri populations, Melophorus ANIC sp. 3 have been collected. These in minor workers, particularly, the cuticle tends to ants, however, are darker in colour, and resemble be shagreenate and may be dull. Melophorus bruneus Plagiolepis lucidula Wheeler. In some goldfields complex sp. JDM 520 is found throughout WA, populations the metanotal groove is very weakly including parts of the metropolitan area. Inspection impressed, but in other populations this groove is of the antennae is needed to distinguish hirsute M. more deeply impressed. The propodeum ranges turneri from M. bruneus sp. JDM 520. Melophorus from smoothly rounded and scarcely raised above bruneus complex sp. JDM 600 is also very similar the mesonotum (seen in outline) to distinctly raised to M. turneri, but lacks semi-erect setae on the hind with an abrupt angle separating the dorsal from the tibiae. Minor workers only of this mainly eremaean declivitous faces. Thus far major workers have not species have been collected; these being taken as far been associated with this ant, despite the ubiquitous west as Westonia. This species appears to be very nature of the minor workers, and an assessment of close to M. bruneus, based on the holotype in ANIC its taxonomic status in relation to Melophorus ANIC (a major worker). sp. 3 is therefore difficult. The minor workers, Melophorus ANIC sp. 3, Melophorus sp. JDM however, can be separated from minor workers of 176 and Melophorus sp. JDM 500 are three small Melophorus sp. JDM 176 by their generally smaller to minute species. The workers are very similar size and smooth, shiny cuticle. in structure and appearance. Minor workers are Melophorus sp. JDM 470, as here defined, may be glabrous, but major workers usually have some a complex of two species, both apparently close to erect setae, these being modified in major workers Melophorus sp. JDM 176. Major and minor workers of Melophorus sp. JDM 176. Melophorus sp. JDM are a little larger than their counterparts within 500 has thus far only been found within a few Melophorus sp. JDM 176, and are decidedly hairy. kilometres of the coast, on white, sandy soil, This is a mainly northern taxon, which occurs in between Perth and Shark Bay. Both major and the upper fringes of the SWBP. Dull little minor minor workers have a mesonotum that is paler workers of Melophorus sp. JDM 1180 were recently than the surrounding mesosoma, sometimes pitfall-trapped in the Eneabba region in a project being white and translucent. In major workers the associated with Curtin University. The species was mesonotum tends to be bulbous. The body colour not uncommon in the traps, and evidence of its varies from yellow to brown. Melophorus ANIC sp. presence in sandplain country in the north of the 3 varies in respect of the mesosoma, which is of an Swan Coastal Plain botanical district would not be even, yellow colour, and the mesonotum, which unexpected. is less pronounced in major workers. The head of Small size is also characteristic of what is the minor worker is also slightly more rounded probably a related group of ants. Melophorus sp. than that of Melophorus sp. JDM 500. This ant is JDM 230 and Melophorus sp. JDM 1063 represent abundant in the wetter south-west corner of the two species in which the posterior sector of the State, including urban areas. Both of these species mesonotum is extended as a lobe in the minor are virtually unsculptured, whereas Melophorus sp. workers, so that it overhangs the propodeum 102 Brian E. Heterick (this feature is less accentuated in major workers, very even dorsal profile. which are known only for Melophorus sp. JDM 230). Melophorus mjobergi Forel and Melophorus sp. JDM Melophorus sp. JDM 230 has thus far been found 784 have a similar appearance and may be related. only in the Perth region, while Melophorus JDM Melophorus sp. JDM 784, however, has scattered, 1063 is represented by a single series from a nest short, thickened setae, whereas the erect setae near the Billabong Roadhouse, south of Shark Bay on M. mjobergi are plentiful, long and thin. Both and from Barrow Island (in the Pilbara, and thus have abundant pubescence on all body surfaces. outside of the SWBP). Apart from the position of the Melophorus mjobergi was described from Broome, in propodeal spiracle, the two taxa are differentiated the Kimberley region. The fact that this species can on the basis of presence or absence of pilosity. also be found within 200 km of Perth, suggests that Melophorus sp. JDM 786, known from a single it has a broad distribution throughout mainland minor worker collected near Southern Cross, Australia. Melophorus mjobergi has been collected and a major and media worker collected east of generally throughout the SWBP. Melophorus sp. Hyden on sand-plain, and Melophorus sp. JDM JDM 784 has been collected in open woodland at 1070, known from minor workers taken from near Dryandra, but is more commonly encountered in Billabong Roadhouse and from Kwelkan in the arid and semi-arid localities. This species forages on eastern wheatbelt, have only slight differences apart tree-trunks as well as on the ground; the Dryandra from the pilosity aspect, and the colour pattern is specimens being collected in an intercept trap set identical. A possible major worker, belonging to on a Wandoo trunk. Minor workers of Melophorus the latter species, was collected at Sandford Rock mjobergi complex sp. 1121 differ from M. mjobergi Reserve in the eastern wheatbelt. The higher- in the more rounded pronotum and mesonotum, level affinities of these and the ants mentioned although the single known major worker of this in the previous paragraph are uncertain, but the species cannot easily be separated from majors appearance of the major workers suggests they of M. mjobergi. Specimens of this species have probably belong to the M. turneri species-group. been collected only at Westonia within the SWBP, Only a few minor worker specimens are known with another minor worker being taken at Queen for Melophorus sp. JDM 1102. The head of this gracile Victoria Spring, outside of the SWBP. Another, little ant has a domed vertex, the mesonotum is larger species, Melophorus sp. JDM 1105, collected straight and the femora are long and thin for much only at Nerren Nerren Stn. (just outside of the of their length. These specimens have been pitfall- NE boundary of the SWBP) may be related to the trapped in and around the Zuytdorp region, north preceding taxa. of Kalbarri. (Media and major workers that could The remaining seven Melophorus species found in belong to this species have been taken in the Pilbara the SWBP have an unmistakeable facies that implies by DEC workers, but unfortunately have not been specialist habits. All are uncommon in the Province, able to be associated with workers of the minor and are known, at the most, from a small handful subcaste from the same area.) of specimens. Melophorus potteri McAreavey was Melophorus insularis Wheeler is the member of the described from Victoria, where these ants are M. aeneovirens species-group found mainly in the known to prey on termites (McAreavey 1947). wetter, open-woodland regions of the south-west, Records from the SWBP have come from Eneabba, but it also occurs at least as far north as Shark Bay. Kellerberrin and West Arthur in the central In more inland areas, particularly in the northern wheatbelt, but the ant appears to be more common and central parts of the State, it is replaced by north of the SWBP.