The Beagle, Records of the Museums and Art Galleries of the Northern Territory, 2003 19: 125-126 Short communication Records of two new ant genera, Anonychomyrma Donisthorpe and Probolomyrmex Mayr (Hymenoptera: Formicidae), for the Northern Territory ALAN N. ANDERSEN Division of Sustainable Ecosystems CSIRO Tropical Ecosystems Research Centre PMB 44, Darwin NT 0822, AUSTRALIA A l an.Andersen@cs iro. an Keywords: Anonychomyrma, Formicidae, Melville Island, Northern Territory, Probolomyrmex greavesi, Solar Village. Andersen (2000) lists 66 ant genera recorded from Three specimens of a species of Anonychomyrma the monsoonal tropics of northern Australia, out of the were recorded in pitfall traps during a fauna survey of 103 total Australian genera (Shattuck 1999). Of the 66 Melville Island conducted by the Biodiversity Unit of monsoonal genera, six (Colobostruma Wheeler, the Northern Territory Department of Infrastructure, Dolichoderus Lund, Mesostruma Brown, Leptomyrmex Planning and Environment during July and August Mayr, Mayriella Forel, and Notoncus Emery) are known 2001. The specimens were from two locations, “Three from the'region only in Queensland, Willowsiella Ways” (11°44'S, 130°59’ E) and “West Jump-up” Wheeler is known only from Western Australia, and (11°35’ S, 130°33’ E). In both cases the habitat was Amblyopone Erichson occurs in both Queensland and eucalypt woodland/open-forest with perennial tussock Western Australia, but remains unrecorded in the grasses on sandy loam soil. Northern Territory. This leaves 58 genera listed from The species-level taxonomy of Anonychomyrma is monsoonal Northern Territory (NT), one of which too poorly resolved to be confident of the identity of (Anoplolepis Santschi) is introduced (Young et at. the Melville Island species. It is a member of the 2001). This represents virtually all known NT ant nitidiceps species group, with erect hairs present on genera; the only exception is Adlerzia Forel, an antennal scapes, but largely absent from the gaster. The undescribed species of which has been collected from specimens are housed at the CSIRO Tropical the Alice Springs region (D. Agosti, personal Ecosystems Research Centre in Darwin. communication). Probolomyrmex Mayr, 1901 Two additional genera, Anonychomyrma This extremely rare ponerine genus is distributed Donisthorpe (Dolichoderinae) and Probolomyrmex throughout the world’s tropics, and consists of 13 Mayr (Ponerinae) have since been collected from the Top End of the NT, and these records are documented described species (Bolton 1995), most known only from here. one or a few records (Taylor 1965). They are small (total length 1.5-2 mm), typically blind ants that nest and Anonychomyrma Donisthorpe, 1947 forage within soil and litter. This genus comprises 30 described species and A single species, P. greavesi Taylor, has been subspecies, distributed from southern Australia to recorded from Australia. It is one of Australia’s rarest Malaysia (Shattuck 1992a,b, 1999). The 14 species and ants, previously known only from a handful of records subspecies listed from Australia are restricted to higher from the eastern seaboard, from Canberra to north rainfall regions of the eastern and southern coasts Queensland (Shattuck 1999). However, in March 2002 (Shattuck 1999). Three Australian species groups can it was collected from leaf litter during an ant survey by be recognised (Andersen 1991; these groups were then CSIRO at Solar Village (12°37’S, 131°06’E), 35 km considered part of Iridomyrmex): the itinerans group, south-east of Darwin. The vegetation of the collecting from subhumid regions of the south-east and south¬ site was open forest dominated by Eucalyptus miniata west; the nitidiceps group, widely distributed but most and E. tetrodonta. Solar Village had been protected common in southern dry sclerophyll forests and from fire for more than 20 years, such that compared heathlands; and the biconvexa group, restricted to with surrounding (frequently burnt) savanna, tree cover wetter forests of the eastern seaboard. The species are highly aggressive and behavioural!}' dominant members was higher, litter was much denser, and grasses were of ant communities where they occur (Andersen 1986). virtually absent (Woinarski et al. in press). 125 A. N. Andersen Twenty-two specimens (all workers) of P greavesi ACKNOWLEDGMENTS were collected from a single 30x30 cm litter sample. This is a greater number of individuals than all previous I am most grateful to John Woinarski who led the Australian records of the genus combined fauna survey of Melville Island and invited CSIRO to (S.O. Shattuck, personal communication). Specimens undertake the ant survey at Solar Village. I also thank are housed in the Australian National Insect Collection Alaric Fisher for providing habitat information for the in Canberra, the CS1RO Tropical Ecosystems Research Anonychomyrma records, and Tony Hertog and Lyn Centre and the Museum and Art Gallery of the Northern Lowe for assisting with the Solar Village work. Territory in Darwin (NTM 11179; 2 specimens). REFERENCES DISCUSSION Andersen, A.N. 1986. Diversity, seasonality and community Many ant taxa are easily overlooked because of their organization of ants at adjacent heath and woodland sites cryptic habits and association with localised habitats. in southeastern Australia. Australian Journal of Zoology In addition to being rare, a number of NT ant genera 34: 53-64. Andersen, A. N. 1991. The ants of southern Australia: a guide are either rainforest specialists (e.g. Mystrium Roger, to the Bassian fauna. CSIRO Publishing: Melbourne. Turneria Forel, Pseudolasius Emery; Reichel and Andersen, A.N. 2000. The ants of northern Australia: a guide Andersen 1996) or occur in a broader range of forest to the monsoonalfauna. CSIRO Publishing: Collingwood. habitats but are highly cryptic (e.g. Leptcinilla Emery, Bolton, B. 1995. A new general catalogue of the ants of the Machomyrma Forel, Rhopalomastix Forel). world. Harvard University Press: Cambridge. Donisthorpe, 11. 1947. Ants from New Guinea, including new Probolomyrmex can be placed in the latter category, species and a new genus. Annals and Magazine of Natural so it is not surprising that it has hitherto been History 13: 577-595. unrecorded in the Northern Territory. However, the Mayr, G. 1901. Stidafrikanische Formiciden, gesammelt von Dr. occurrence on Melville Island of a species of Hans Brauns. Annalen des k.k. Naturhistorischen Anonychomyrma is surprising, given it is a highly Hofmuseums Wien 16: 1-30. active, epigaeic species of savanna woodland, and Reichel, H. and Andersen, A.N. 1996. The rainforest ant fauna of Australia’s Northern Territory. Australian Journal of therefore not so easily overlooked. Zoology 44: 81-95. The nearest known record of Anonychomyrma in Shattuck, S. O. 1992a. Review of the dolichoderine ant genus Australia is from coastal north Queensland. It has not Iridomyrmex Mayr with descriptions of three new genera been recorded from north Queensland west of the Great (Hymenoptera: Formicidae). Journal of the Australian Dividing Range, or from the coastal plains of the Entomological Society 31: 13-18. Darwin region, despite extensive collecting. The Shattuck, S. O. 1992b. Generic revision of the ant subfamily Dolichoderinae (Hymenoptera: Formicidae). Sociobiology species might also occur in Arnhem Land, most of 21: 1-181. which has been poorly collected for ants, or possibly Shattuck, S. O. 1999. Australian ants: their biology and even in South-east Asia. The possibility of it being identification. CSIRO Publishing: Melbourne. introduced to Melville Island also cannot be ruled out, Taylor, R. W. 1965. A monographic revision of the rare although this would seem unlikely given that its two tropicopolitan ant genus Probolomyrmex Mayr known locations are remote from human settlement. (Hymenoptera: Formicidae). Transactions of the Royal Entomological Society of London 117: 345-365. There is therefore a strong likelihood that the Melville Woinarski, J. C. Z., Rislcr, J., and Kean, L. (in press). The Island species is endemic there. Both its records on response of vegetation and vertebrate fauna to 23 years Melville Island lie within the general area of a proposed of fire exclusion in a tropical Eucalyptus open forest, major acacia plantation, which raises concerns over its Northern Territory, Australia. Austral Ecology. conservation status. Young, G. R„ Beilis, G. A., Brown, G. R. and Smith, E. S. C. 2001. The crazy ant Anoplolepis gracilipes (Smith) (Hymenoptera: Formicidae) in east Arnhem Land, Australia. Australian Entomologist 28: 97-104. Accepted 9 May 2003 126