Drosophila vulcana, Graber, 1957

Yassin, Amir, Suwalski, Arnaud & Raveloson Ravaomanarivo, Lala H., 2019, Resolving the synonymy and polyphyly of the ‘ Drosophila bakoue species complex’ (Diptera: Drosophilidae: ‘ D. montium species group’) with descriptions of two new species from Madagascar, European Journal of Taxonomy 532, pp. 1-26 : 18

‘ D. vulcana species complex’ new complex

Figs 1–2 , 3C , 8 A–D, 9A–F

Diagnosis

Male abdominal tergites yellow, T2–T4 with broad brown or black stripes, T5 and T6 with a thin black stripe expanding on the middle and fainting towards the margin ( Fig. 8A ); cercal ventral lobe (secondary clasper) partially separated from cerci with two or three very large curved black medial teeth on the internal margin; surstylus with a lateral row of strong, short prensisetae on the outer and inner margins (no medial prensisetae), the innermost one significantly long; hypandrial median process tapering ( Fig. 3C ); aedeagus hirsute with cuticular scales; inner paraphyses as long as aedeagus, with finely serrated margins ( Fig. 9 A–D). Female abdominal tergites darker than male’s ( Fig. 8B ).

Remarks

Chassagnard et al. (1997) mentioned a species, named ‘ Drosophila (Sophophora) sp. C’, belonging to the ‘ D. montium species group’ in Malawi with males having diffuse brown T2–T4 and pale T5 and T6. This species either belongs to one of the two species of this complex or represents a new species belonging to the complex. Elucidating its identity needs further investigation.

Taxon content

D. vulcana Graber, 1957 .

D. seguyiana sp. nov.

Figures

Fig. 1. Bayesian phylogeny of 19 species from the ‘D. montium species group’ Da Lage, 2007 inferred from complete mitochondrial genomes. Nodes supported by 100% posterior probability (pp) are not labeled, those with pp> 90% or 60% are labeled with gray and white circles, respectively. Species belonging to the ‘D. bocqueti species complex’ and the ‘D. bakoue species complex’ are highlighted in orange and green, respectively. ‘K’ and ‘B’ refer to the strains of D. aff tsacasi Bock & Wheeler, 1972 from Kenya and Bioko Island, respectively.

Fig. 2. Comparison of Bayesian phylogenies of the ‘D. seguyi species subgroup’ Yassin, 2018 inferred from mitochondrial COI (left) and nuclear Amyrel (right) genes. Nodes supported by>95% posterior probability (pp) are labeled with black circles. An asterisk refers to species sequenced here, whereas two asterisks refer to the sequence of D. vulcana Graber, 1957 of Da Lage et al. (2007), which turned out to belong to D. seguyi Smart, 1945 from Kenya (see the text). Note the discrepancy in position of different geographical strains of D. bakoue Tsacas & Lachaise, 1974 (in red) between the two genes. Species belonging to ‘D. bocqueti species complex’ Tsacas & Lachaise, 1974, ‘D. bakoue species complex’ Rafael, 1984, ‘D. nikananu species complex’ Tsacas & Chassagnard, 1992, and ‘D. megapyga species complex’ Lachaise & Tsacas, 2001 are highlighted in orange, green, yellow and red, respectively.

Fig. 3. Photomicrographs of male periphallic organs. A. D. seguyi Smart, 1945 (MNHN). B. D. aff. tsacasi Bock & Wheeler, 1972 (MNHN). C. D. mylenae David & Yassin sp. nov. (MNHN). Scale bars = 0.1 mm.

Fig. 8. Adult habitus. A–B. D. vulcana Graber, 1957 (MNHN). A. ♂. B. ♀. C–D. D. mylenae David & Yassin sp. nov. (MNHN). C. ♂. D. ♀. Scale bar = 1 mm.

Fig. 9. Terminalia of the ‘D. vulcana species complex’. A, C, E. D. vulcana Graber, 1957 (MNHN). A, C. ♂. E. ♀. B, D, F. D. mylenae David & Yassin sp. nov. (MNHN). B, D. ♂. F. ♀. Scale bars: A–B = 50 µm; D–F = 100 µm.