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Diptera: Drosophilidae), with Historical Overview © The Authors, 2015. Journal compilation © Australian Museum, Sydney, 2015 Records of the Australian Museum (2015) Vol. 67, issue number 5, pp. 129–161. ISSN 0067-1975 (print), ISSN 2201-4349 (online) http://dx.doi.org/10.3853/j.2201-4349.67.2015.1651 New Species in the Drosophila ananassae Subgroup from Northern Australia, New Guinea and the South Pacific (Diptera: Drosophilidae), with Historical Overview SHANE F. MCEVEY* AND MICHELE SCHIffER1 Australian Museum Research Institute, 6 College Street, Sydney NSW 2000, Australia 1 School of Biosciences, University of Melbourne, Parkville Victoria 3010, Australia [email protected] ABSTRACT. Three new Drosophila species are described in the ananassae subgroup from Australia, New Guinea and Samoa. Drosophila pandora sp.nov. and D. anomalata sp.nov. are morphologically very similar to the circumtropical species D. ananassae and are classified together in theananassae complex. For 40 years D. pandora has been incorrectly identified as D. ananassae in the Australian tropics. The results of a detailed examination of the morphology of 1649 wild-caught ananassae-like male specimens, sampled from 60 islands from Southeast Asia to French Polynesia and 94 localities of northern Australia and western, central and eastern New Guinea, are reported. Comparisons are made with Afrotropical and Oriental samples to confirm the identity ofD. ananassae s.str. Photomicrographs of the male terminalia and sex combs of D. ananassae and D. pandora from geographically distant localities demonstrate the stability of the important diagnostic characters. Males of D. anomalata, known only from three localities in Queensland, Australia, have a unique bobbing behaviour when courting, and they have the lowest total number of teeth in the sex combs. The distinctive male terminalia of related species D. atripex, D. monieri, D. ochrogaster, D. parapallidosa and D. pallidosa are figured for comparison. Among them, a species from Samoa, closely resembling the Fijian endemic species D. phaeopleura, is described here as Drosophila schugi sp.nov. MCEVEY, SHANE F., AND MICHELE SCHIFFER. 2015. New species in the Drosophila ananassae subgroup from northern Australia, New Guinea and the South Pacific (Diptera: Drosophilidae), with historical overview. Records of the Australian Museum 67(5): 129–161. KEYWORDS. Drosophilidae; Drosophila ananassae; taxonomy; biogeography Bock & Wheeler (1972) revised the Drosophila melanogaster complexes have been added for species from Madagascar species group (Sturtevant, 1942) worldwide and classified 64 and the Seychelles. There are now 336 species in the species into 11 subgroups, one of which—the D. ananassae melanogaster species group, they are in 27 subgroups, 25 subgroup (Hsu, 1949)—was subdivided into the bipectinata species are in the ananassae subgroup; 15 of the 25 species complex (in males of which the aedeagus is bifid and bare), have not formally been placed in any species complex. and the ananassae complex (in males of which the aedeagus Fieldwork since 1972 in New Guinea, northern Australia is fused and strongly hirsute) (Bock, 1971). Two additional and the South Pacific has yielded an enormous cache * author for correspondence 130 Records of the Australian Museum (2015) Vol. 67 Figure 1. Distribution of 11 of the 12 Drosophila ananassae complex species, the authors have collected at red dot localities or examined specimens collected by others from red circle localities; these data are complete for the Australian Region and incomplete for the Oriental Region. Drosophila lachaisei Tsacas, 1984 from Africa is not shown. The Drosophila pandora sp.nov. type locality is Lake Placid near Cairns (see inset); the D. anomalata sp.nov. type locality is Deeragun near Townsville. Drosophila ananassae s.str. is pantropical within the pale blue lines, the Ambon type locality is shown; D. ananassae extends as far south as Corindi in Australia, it is absent in Sydney and New Zealand. Three or more additional, but undescribed species, occur in New Guinea (and perhaps also in northern Australia), these are not shown. Islands of Torres Strait: (1) Mabuiag, (2) Moa, (3) Thursday, and (4) Mount Adolphus; and localities on Cape York Peninsula: (5) Bamaga, (6) Bertie Creek and Heathlands homestead, (7) Doublemouth and Gunshot Creeks, (8) Gordon Creek, (9) Iron Range (nr airstrip), and (10) upper Peach Creek (McIlwraith Range) are indicated (see inset). Geospatial coordinates of all localities are given in Appendix 1. of specimens which has enabled us to undertake a very similar species collected within and near the known comprehensive comparative morphological study of the range of the new species. Teams of biologists, primarily species similar to Drosophila ananassae in this region. In in Japan, the United States and Australia, have, for many this paper we describe three new species in the ananassae decades, used live strains of “Drosophila ananassae”— subgroup, two of which are in the ananassae complex. established from flies collected from the New Guinea region and islands of the South Pacific—to explore various important questions in evolutionary biology. Unfortunately, Historical overview many of the significant cytological, karyological, and To introduce the discovery of these cryptic species, it is behavioural discoveries have been published using informal necessary to provide historical, biogeographic, genetic strain-names and codes and their utility over the decades has and taxonomic context that is more expansive than usual. been found wanting because reliable voucher specimens are Drosophila pandora has been confused, especially in now difficult to find or are lost. In the following discussion, Australia, with the cosmopolitan species Drosophila advances in taxonomy are introduced in approximate ananassae—an extremely important model species used in chronological order to help explain how certain assumptions hundreds of labs worldwide. The possibility that anomalous have, in some ways, inhibited overall progress. The authority experimental outcomes are attributable to there being more of a school of thought or a single major publication often than one species under study, is worth exploring. has strongly influenced the direction of enquiry. At the end Quite apart from the availability of a range of formal and of this work we conclude that the centre of diversity for the informal potential synonyms, there is also a very long history ananassae complex is New Guinea. New Guinea and the of intensive population, genetic and evolutionary study of northern part of Cape York Peninsula, is a tropical region McEvey & Schiffer: Australian Drosophila ananassae subgroup 131 that has had continuous, land-connected, lowland rainforest with local D. ananassae (Moriwaki, 1993). From the 1930s for most of the last two hundred thousand years (Williams, onwards, various Japanese and North American researchers 2001). and their students made D. ananassae the principal model Carl Ludwig Doleschall (1859) discovered and named for genetic investigation—the species, as a living culture, Drosophila ananassae at Ambon, just to the west of was easily sustained in labs. Moriwaki began working with New Guinea where he was based as a young doctor and Drosophila ananassae mutant strains in Japan in 1931. entomologist (Fig. 1, Indonesia). At the time he read the Kaufmann studied D. ananassae cytology at the University publications describing insects that were being collected of Alabama, publishing results in 1936–1937. Moriwaki by his contemporary—Alfred Russell Wallace—further to collaborated with Kikkawa in Komai’s lab at Kyoto and the west in the Dutch East Indies (= modern Indonesia). by 1938 Kikkawa and Moriwaki had discovered over 100 Wallace sent his specimens back to London where Walker mutations of D. ananassae, and spontaneous crossing over described them. Doleschall stayed abreast of Wallace’s in males. Despite dispersing four replicates of their large and discoveries because copies of Walker’s publications were valuable collection of mutant stocks prior to WWII, none being sent to him by Bleeker. Soon after receiving two works survived. From 1948, collaboration with Dobzhansky and (Journal of the Proceedings of the Linnean Society 1856) Patterson resulted in renewed investigation of D. ananassae enumerating new dipterous species Wallace had collected in in Japan and in the United States (Moriwaki, 1993). Not Singapore, Malacca, Sarawak and Borneo, Doleschall and withstanding the significant growth in the use of various Wallace actually met at Ambon in December 1857. Five other Drosophila species worldwide as model organisms months later, in May 1858, Doleschall collected specimens in genetics, it is the evidence of population structure in D. in Ambon that were subsequently to become the types of his ananassae (cf. D. melanogaster) that elevates its status as new species Drosophila ananassae Doleschall, 1859. He an ideal model for the study of natural selection on genomic described their abundance as Zeer talrijk op saprijke zoete variation (Schug et al., 2007). vruchten die reeds in bederf beginnen te overgaan; vooral “Among the relatively small number of species in the op de rijpe vruchten van ananas [numerous on sappy and genus Drosophila that have been subjected to cytogenetic sweet fruit which has become overripe; especially on ripe analysis, D. ananassae is unique in having appreciable pineapple]. Having carefully read Wallace’s Linnean Society levels of meiotic crossing over in males (Kikkawa,
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