Current status of theDrosophila melanogasterspecies‐group (Diptera)

Abstract

The Drosphila melanogaster species-group, established by Sturtevant (1942) for fourteen species, is now known t o contain 115 described species here divided into twelve named subgroups (including one newly proposed), as well as further undescribed species. Three of the species, melanogaster, simulans and ananassae, are cosmopolitan; two others, kikkawai and malerkotliana, are widespread in the southern hemisphere, the latter apparently a recent introduction t o South America. The greatest numbers of species otherwise occur in the Oriental region with smaller numbers in the Ethiopian, eastern Palaearctic and Australian regions and in several islands of the South Pacific. Dmjasekari and D,raychaudhurii are synonymized with D. biamipes; Definition of the melanogaster species-group (Sturtevant, 1942: 29) As members of the subgenus Sophophora, species of the melanogaster group are characterized inter aliu by relatively narrow cheeks and possession (in most species) on the abdominal tergites of dark posterior bands 0307-6970/80/1000-0341 $02.00 0 1980 Blackwell Scientific Publications 24 34 1 342 Ian R . Bock 38,291-307. Zetterstedt, J.W. ( I 847) Diptera scandinaviae disposita et descripta, 6.

Evolution of the chromosomal location of rDNA genes in two Drosophila species subgroups: ananassae and melanogaster

“…Its inclusion in the ananassae subgroup was initially challenged, on the basis of some characteristics of its periphallic organs (Bock and Wheeler, 1972). Recent molecular data support this assignation, but do not enlighten us about the relationships of this species with the three complexes (Schawaroch, 2002).…”

“…In the melanogaster subgroup, the phylogenetic relationships are clear, except for the simulans-sechellia-mauritiana triad. In the ananassae subgroup, morphological, molecular, karyotypic and behavioural data strongly support a division into three complexes ananassae, bipectinata and ercepeae (Bock and Wheeler, 1972;Lemeunier et al, 1986Lemeunier et al, , 1997Schawaroch, 2002;Da Lage, personal communication). However, the phylogenetic relationships of the complexes have not been resolved, nor is the positioning of D. varians, a species that does not seem to fit into any of these complexes.…”

New African species in the Drosophila obscura species group: genetic variation, differentiation and evolution

“…In view of affinities with the melanogaster species group, Throckmorton (1975) derived the obscura species group from a primeval protomelanogaster/obscura trunk. On the basis of diversity criteria the origin of the melanogaster species group is assumed to be oriental (Bock and Wheeler, 1972;Bock, 1980;Tsacas, 1984;Lemeunier et a!., 1986). A plausible scenario is to consider that from that centre of origin the protoobscura stock first split into two ancestral lineages, one of them diversifying in East Africa and the other extending to Europe, where it differentiated giving rise subsequently to both the New World pseudoobscura and affinis lineages.…”

Microscale laser surgery reveals adaptive function of male intromittent genitalia

“…We refer to these genital spines as intromittent because they insert into female external genitalia during copulation, and not because they insert into the reproductive tract. The spines exhibit a pattern of pronounced diversification among closely related species, and they are of notable taxonomic importance (Bock & Wheeler 1972).…”