Independent evolution of the same set of characters in fig flies (Lissocephala,Drosophilidae)

Summary Comparison of species of African fig flies (Lissocephala, Drosophilidae) shows that an unusual phenotype has evolved independently when a particular environment prevails. Each time the adaptation is observed, associated morphological and behavioural characters also appear. Such convergence suggests that selection operates on sets of predetermined morphogenetic pathways.     

The subgenus Ashima (Diptera,Drosophildae, Phortica) from China,with DNA barcoding and descriptions of three new species

In the present study, three new species found in Yunnan, Southwest China were described as members of the subgenus Phortica (Ashima): P. (A.) haba An & Chen, sp. nov., P. (A.) montipagana An & Chen, sp. nov. and P. (A.) qingsongi An & Chen, sp. nov. Barcode sequences (partial sequences of the mitochondrial COI gene) were collected from 61 specimens of 16 known and the above-mentioned three new Ashima species. The intra- and interspecific pairwise K-2P (Kimura two-parameter) COI distances were analysed and a phylogenetic tree was constructed based on the barcode sequences. Species delimitation in this subgenus was supported by integrating barcodes with morphological information, in particular for the three new species, considered to be cryptic species. In addition, the diversification of lineages in the subgenus Ashima was proposed to occur in southern China and adjacent areas, suggesting specific adaptation of Ashima species to the high plateau environments.

http://zoobank.org/urn:lsid:zoobank.org:pub:69A81D0E-5993-426D-9B59-A2AC5E52BD84     

The genus Apsiphortica from China with DNA barcoding information (Diptera: Drosophilidae)

Two new species of the genus Apsiphortica are described from China: A. orthophallos n. sp. and A. sinuatipenis n. sp. Species delimitations are improved by integrating morphological and DNA barcoding information. The intra- and interspecific pairwise p-distances (proportional distance) are summarized for five Apsiphortica species from China. Furthermore, nucleotide sites with fixed status in the alignment of the COI sequences (639 nucleotide sites in length) are used as “pure” molecular diagnostic characters to delineate the five species. A key to all the Chinese species of the genus Apsiphortica is provided.     

Mesosternal bristle number in a cosmopolitan drosophilid: an X-linked variable trait independent of sternopleural bristles

Mesosternal (MS) bristles in Drosophila are a pair of machrochaetae found at the sternal end of the sternopleural (STP) microchaetae, and are thought to be invariable. In a closely related drosophilid genus, Zaprionus, their number is four and, in contrast to Drosophila, they show interspecific and intraspecific variability. The genetic basis of MS bristle number variability was studied in Z. indianus, the only cosmopolitan species of the genus. The trait responded rapidly to selection and two lines were obtained, one lacking any bristles (0-0) and the other bearing the normal phenotype (2-2). Other symmetrical phenotypes, (1-1) and (3-3), could also be selected for, but with lesser success. By contrast, STP bristle number did not vary significantly between the two lines (0-0) and (2-2), revealing its genetic independence from MS bristle number. Reciprocal crosses between these two lines showed that MS bristle number is mainly influenced by a major gene on the X chromosome (i.e. F₁ males always resembled their mothers) with codominant expression (i.e. heterozygous F₁ females harboured an average phenotype of 2 bristles). However, trait penetrance was incomplete and backcrosses revealed that this variability was partly due to genetic modifiers, most likely autosomal. The canalization of MS bristle number was investigated under different temperatures, and the increased appearance of abnormal phenotypes mainly occurred at extreme temperatures. There was a bias, however, towards bristle loss, as shown by a liability (developmental map) analysis. Finally, when ancestral and introduced populations were compared, the latter were far less stable, suggesting that genetic bottlenecks may perturb the MS bristle number canalization system. MS bristle number, thus, appears to be an excellent model for investigating developmental canalization at both the quantitative and the molecular level.     

不同成熟度杨梅果实上果蝇的动态变化

【目的】果蝇类害虫是杨梅果实的主要害虫,本文旨在探讨果蝇对不同成熟度果实的选择倾向以及杨梅园果蝇动态变化规律。【方法】通过饲养获得黑腹果蝇Drosophila melanogaster种群,探讨果蝇在不同成熟度杨梅果实上的繁殖量,通过果园调查统计杨梅成熟过程中落果数量、落果和树上挂果中果蝇数量。【结果】杨梅成熟过程中,果色经历绿色、粉红色、红色和紫红色变化过程;果蝇分别在各种成熟度果实上繁殖时,绿色果实上果蝇后代数量最少,但接近成熟的粉红色、红色和紫红色果实上果蝇后代数量无显著差异;同时提供各种成熟度的果实时,随着果实成熟度增加,黑腹果蝇的后代繁殖数量增多。在果实成熟前后对果园果蝇数量的调查表明,在果实成熟前,落果中果蝇数量显著高于树上挂果,落果是果园果蝇的主要繁殖地;但当果园果实大量成熟时,挂果中果蝇数量显著多于落果,挂果成为果蝇主要繁殖场所。【结论】在杨梅园,果蝇存在从地面落果转移至树上挂果的动态变化,果蝇对不同成熟度果实的选择性差异可能是这种动态变化的主要原因。     

中国冠果蝇属一新种和二新记录种及DNA条形码信息(双翅目:果蝇科)

基于形态学和分子遗传学证据,描述了冠果蝇属1新种Stegana(Stegana)helvippecta sp.nov.和2中国新记录种:S.(S.)furta(Linnaeus,1767)和 S.(S.)taba Okada,1971;利用41 条 DNA 条形码信息,分析了18种冠果蝇的遗传距离,并提供了中国产全部18种冠果蝇的形态图及分种检索表.     

Six new species of the subgenera Alloparadisa and Ashima (Diptera: Drosophilidae: Phortica) from Yunnan,China, with DNA barcoding information

Six new species of the genus Phortica are described from Yunnan, Southwest China: P. (Alloparadisa) kaibangya n. sp., P. (Ashima) semiannulata n. sp., P. (Ashima) dianmianensis n. sp., P. (Ashima) idiasta n. sp., P. (Ashima) menglian n. sp. and P. (Ashima) zhangyuanae n. sp. The 22 new DNA sequences of the mitochondrial COI gene with BOLD Process ID and GenBank accession numbers are provided for the six new species and six related known species from southern China: P. (Ashima) glabra, Chen & Toda, 2005 P. (Ashima) nudiarista Cheng & Chen, 2008, P. (Ashima) saltiaristula Chen & Wen, 2005, P. (Ashima) spinosa, Chen & Toda, 2005 P. (Ashima) symmetria Chen & Toda, 2005 and P. (Ashima) yiqini Zhu & Chen, 2017. The pairwise interspecific K-2P COI distances among all Chinese species of the subgenera Alloparadisa and Ashima are summarized. An identification key to males of all Chinese species of the subgenera Alloparadisa and Ashima is provided.     

The Stegana (sensu stricto) species from China,with morphological and molecular evidence (Diptera: Drosophilidae)

Four new species of the subgenus Stegana (sensu stricto) were found and described from China: S. (S.) antha sp. nov., S. (S.) latiorificia sp. nov., S. (S.) huangjiai sp. nov. and S. (S.) nigrifoliacea sp. nov. Three known Stegana (s. str.) species from China: S. (S.) antlia Okada, 1991, S. (S.) cheni Sidorenko, 1997 Sidorenko, V. S. (1997). New Asian species and new records of the genus Stegana Meigen (Diptera, Drosophilidae). I. Subgenera Oxyphortica Duda and Stegana s. str. Annales d la Société Entomologique de France (N. S.), 33, 65–79.[Web of Science ®] , [Google Scholar] and S. (S.) emeiensis Sidorenko, 1997 Sidorenko, V. S. (1997). New Asian species and new records of the genus Stegana Meigen (Diptera, Drosophilidae). I. Subgenera Oxyphortica Duda and Stegana s. str. Annales d la Société Entomologique de France (N. S.), 33, 65–79.[Web of Science ®] , [Google Scholar] are redescribed as supplementary information. A key to the species, based on morphological characters, is provided. The phylogenetic relationships among 14 species of the subgenus Stegana are reconstructed with the combined sequences of the mitochondrial genes, ND2 (NADH dehydrogenase subunit 2) and COI (cytochrome c oxidase, subunit I). Moreover, the intra- and interspecific pairwise K-2P (Kimura's two-parameter) distances among these species are summarized, and the availability of mitochondrial markers in the species identification of the subgenus Stegana are further discussed.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:368C55C3-B101-457C-BD61-BDD8F1B780E5