Molecular Phylogenetics and Evolution 55 (2010) 335–339 Contents lists available at ScienceDirect Molecular Phylogenetics and Evolution journal homepage: www.elsevier.com/locate/ympev Short Communication Polyphyly of the Zaprionus genus group (Diptera: Drosophilidae) Amir Yassin a,*, Jean-Luc Da Lage a, Jean R. David a, Masanori Kondo b, Lilian Madi-Ravazzi c, Stéphane R. Prigent d, Masanori J. Toda e a Laboratoire Evolution, Génomes et Spéciation (LEGS), Centre National de la Recherche Scientifique (CNRS), Av. de la Terrasse, 91198 Gif-sur-Yvette Cedex, France b Biosystematics Laboratory, Kyushu University, 810-8560 Fukuoka, Japan c Departamento de Biologia, UNESP (Universidade Estadual Paulista), 15054-000 São José do Rio Preto, SP, Brazil d Research Center for Biodiversity, Academia Sinica, 11529 Taipei, Taiwan e Institute of Low Temperature Science, Hokkaido University, 060-0819 Sapporo, Japan a r t i c l e i n f o a b s t r a c t Article history: The Zaprionus genus group comprises three drosophilid genera (Zaprionus, Phorticella and Samoaia) that Received 10 July 2009 are thought to be related to the Drosophila immigrans species group. We revised the phylogenetic rela- Revised 8 September 2009 tionships among the three genera and their placement within the subfamily Drosophilinae using one Accepted 9 September 2009 mitochondrial (COII) and one nuclear (Amyrel) gene. The Bayesian tree inferred from concatenated amino Available online 15 September 2009 acid sequences of the two genes strongly suggests the polyphyly of the Zaprionus genus group and of each of the genera Zaprionus and Phorticella. Paraphyly of the D. immigrans species group was also shown here; Keywords: the quadrilineata subgroup formed the sister clade to the genus Samoaia. These results suggest the neces- Genus concept Drosophila sity of taxonomic revisions for some relevant genera and species groups included within the genus Notal pattern Drosophila. Nomenclature Ó 2009 Elsevier Inc. All rights reserved. 1. Introduction Oriental-Australasian region, except P. (X.) madagascariensis Chas- sagnard & McEvey which is endemic to Madagascar. Okada and The drosophiline genera Zaprionus Coquillett and Phorticella Carson (1983) suggested, however, Phorticella s.s. to be close to Duda are characterized by the presence of silvery white longitudi- Scaptodrosophila Duda, a relatively distant genus from Zaprionus nal stripes on the frons and the mesonotum. These stripes have and Drosophila s.s., in light of the morphology of male genitalia. long been hypothesized to be homologous between the two genera Grimaldi (1990) erected many genus groups to include dro- so that Phorticella was once considered a subgenus of Zaprionus sophilid genera that were believed to be monophyletic in light of (Sturtevant, 1927). Wilson et al. (1969) considered both genera morphological characters. One of these groups was the Zaprionus along with two others (Chaetodrosophillela Duda and Samoaia genus group containing three genera that share a single synapo- Malloch) to be ‘‘fairly certainly related to the immigrans” species morphy: a broad facial carina that is extended to oral margin, group of the genus Drosophila. Throckmorton (1975) suggested prominent and rounded on edge. These genera were Zaprionus with that ‘‘the entire cluster [i.e. the immigrans group and the allied gen- its two subgenera, Phorticella and Samoaia. Zaprionus and Phorticel- era] is, in reality, a close-knit lineage little justifying the nomencla- la were believed to be monophyletic in light of their bulbous clyp- tural industry expanded on it.” Okada and Carson (1983) eus, longitudinal stripes and epandrial setation. However, Grimaldi apparently resolved the taxonomic confusions between Zaprionus (1990) used, as a representative species for Phorticella, the species and Phorticella, showing each to be a separate genus comprising P. argentostriata (Bock), and for the subgenus Anaprionus, the two subgenera. Currently, the genus Zaprionus consists of 56 species Z. multistriatus Sturtevant. Both species are junior species, of which 46 belong to the Afrotropical subgenus Zaprionus synonyms of Z. bogoriensis Mainx (Wynn and Toda, 1988). Later sensu stricto and 10 to the Oriental-Australasian subgenus Anapri- molecular phylogenetic studies have failed to reconfirm the sister onus Okada. The genus Phorticella consists of 11 species, of which relationship of Zaprionus and Samoaia, placing the latter closer, seven belong to the subgenus Phorticella s.s. and four to the subge- basally to the clade including the Drosophila immigrans group nus Xenophorticella. All Phorticella species are found in the (Pélandakis and Solignac, 1993; Tatarenkov et al., 2001; Robe et al., 2005; O’Grady and DeSalle, 2008; Yassin et al., 2008). Fur- thermore, Zaprionus appears to be more related to the D. repletoides * Corresponding author. Present address: Sackler Institute for Comparative group [Yassin et al., 2008; cited as the D. tumiditarsus group: how- Genomics, American Museum of Natural History (AMNH), Central Park West at 79th St., 10024 NY, USA. Fax: +33 1 69 82 37 36. ever, D. tumiditarsus Tan, Hsu & Sheng, 1949 was synonymized E-mail address: [email protected] (A. Yassin). with D. repletoides Hsu, 1943 by Wheeler (1981)], a monotypic 1055-7903/$ - see front matter Ó 2009 Elsevier Inc. All rights reserved. doi:10.1016/j.ympev.2009.09.013 336 A. Yassin et al. / Molecular Phylogenetics and Evolution 55 (2010) 335–339 group of unclear phylogenetic position. The D. immigrans group has Z. lineosus (Walker). Yassin et al. (2008) considered the misidenti- been shown to be polyphyletic with respect to other Drosophila s.s. fied Z. lineosus to be a newly cryptic one but further morphological groups and some drosophiline genera (Katoh et al., 2007). examination revealed that it was also Z. bogoriensis. All these taxa Unfortunately, none of the previous morphological or molecular belong to the subfamily Drosophilinae, and thus the genus Leu- revisions have included Phorticella species, because these species cophenga Mik of the subfamily Steganinae was taken as an are rarely captured by standard Drosophila collection techniques outgroup. and are difficult to culture in the laboratory (unlike Zaprionus s.s., some Anaprionus, Samoaia and many Drosophila species). Nothing is known about their life history traits or chromosomal configura- 2.2. Molecular phylogenetic analysis tions. The recent discovery of many Anaprionus and Phorticella spe- cies in Malaysia (Kondo and Toda, in prep.) and Taiwan (Prigent, in DNA extraction, amplification of the two genes (COII and Amy- prep.), and the rare species P. (X.) madagascariensis Chassagnard & rel) and sequencing were conducted using the same protocols as McEvey in Madagascar (Yassin and David, in prep.), has prompted in Yassin et al. (2008). Nucleotide sequences were viewed and us to conduct the present molecular phylogenetic revision of the manually edited using MEGA ver. 4 program (Kumar et al., 2008). genus group using DNA sequences of one mitochondrial (mtDNA) They were deposited in GenBank with accession numbers given gene, cytochrome oxidase subunit 2 (COII) and one nuclear gene in Table 1. Multiple alignments were performed using ClustalW (Amyrel). The results strongly suggest the polyphyly of the Zapri- (Thompson et al., 1994) under the MEGA default parameters. Sta- onus genus group, as well as of both genera Zaprionus and Phorticel- tionarity of base composition was tested using the ENCprime soft- la. Based on the results, we discuss some taxonomic and ware package (November, 2002). Because of the observed nomenclatural revisions that should be implemented. significant departure from stationarity in the Amyrel sequences, DNA of both genes was translated into amino acid sequences. Phy- logenetic relationships were inferred using Bayesian analysis as 2. Materials and methods implemented in MrBayes ver. 3.1.1 program (Ronquist and Huel- senbeck, 2003), under the JTT + C + F substitution model, as pro- 2.1. Sampled species posed by the ProtTest program (Abascal et al., 2005). Posterior probability was estimated as clade support for each internal node, The list of the species used in this study is given in Table 1. Only after a run of 2,000,000 generations with a sample frequency of exemplars of genera and groups relevant to this study were sam- 100 generations and a burn-in period of 5000 generations. pled in light of previous phylogenetic studies: i.e. all the genera and subgenera of the Zaprionus genus group, the genus Scaptodros- ophila, Drosophila melanogaster Meigen (the type species of the 3. Results subgenus Sophophora Sturtevant), D. funebris (Fabricius) (the type species of the genus Drosophila), D. repletoides, and four subgroups Fig. 1 shows the Bayesian phylogenetic tree of the sampled taxa, of the D. immigrans group. Only two species were sampled from the with posterior probability value at each internal node. The subge- subgenus Zaprionus, as the phylogeny of its nearly 50 species has nus Phorticella appears as the earliest branching lineage, followed recently been revised using molecular and morphological charac- by the genus Scaptodrosophila, and then D. melanogaster, the sole ters (Yassin et al., 2008). The subgenus Anaprionus has usually been representative of the subgenus Sophophora of the genus Drosophila represented in previous molecular phylogenetic investigations in this study. The remaining taxa form a clade, Drosophila s.l., con- (Pélandakis and Solignac, 1993; Da Lage et al., 2007)