Abstract
There is a general consensus that the genus Schistura (Nemacheilidae), currently with 241 species, is not monophyletic. However, weak morphological synapomorphies and a lack of genetic data for most species of Schistura and their presumptive relatives have prevented meaningful diagnoses of species groups within this genus. To aid in deciphering evolutionary relationships, sequence data from two mitochondrial genes (cytochrome b and D-loop) were implemented in phylogenetic analyses for species of Schistura and other nemacheilids for which data from earlier studies and recently collected material were available. This analysis of 67 nemacheilid species, including 28 species of Schistura, provides the most comprehensive phylogeny of Nemacheilidae to date. In the phylogenetic tree for the combined data set, species of Schistura clustered in three clades. One clade contained 14 species of Schistura and Sectoria heterognathos and was sister to Homatula. A second clade of 11 species of Schistura was in a larger clade with Turcinoemacheilus kosswigi and Nemacheilus corica. The third clade contained three species, all from the Mae Khlong basin of Thailand. Taxonomic implications of these results are discussed; however, a more taxon-rich dataset and nuclear sequence data are needed before making taxonomic changes.
References
Bănărescu, P. & Nalbant, T.T. (1966) Cobitidae (Pisces) from Afghanistan and Iran. Videnskabelige Meddelelser Dansk Naturhistorisk Forening, 129, 149–186.
Bănărescu, P. & Nalbant, T.T. (1968) Cobitidae (Pisces, Cypriniformes) collected by the German India Expedition. Mitteilungen aus dem Hamburgischen Zoologischen Museum und Institut, 65, 327–351.
Bănărescu, P. & Nalbant, T.T. (1974) The species of Schistura (=Homatula) from the upper Yangtze drainage (Pisces, Cobitidae). Revue Roumaine de Biologie, 19, 95–99.
Bănărescu, P. & Nalbant, T.T. (1995) A generical classification of Nemacheilinae with description of two new genera (Teleostei: Cypriniformes: Cobitidae). Travaux du Muséum National d'Histoire Naturelle "Grigore Antipa", 35, 429–496.
Bohlen, J. & Šlechtová, V. (2013) Schistura puncticeps, a new species of loach from Myanmar (Cypriniformes: Nemacheilidae). Ichthyological Exploration of Freshwaters, 24, 85–92.
Deng, H., Wen, H., Xiao, N. & Zhou, J. (2016) A new blind species of the cave genus Oreonectes from Guizhou, China (Nemacheilinae). ZooKeys, 637, 47–59.
https://doi.org/10.3897/zookeys.637.10202Edgar, R.C. (2004) MUSCLE: multiple sequence alignment with high accuracy and high throughput. Nucleic Acids Research, 32, 1792–1797.
https://doi.org/10.1093/nar/gkh340
Endruweit, M., Yang, J.X. & Liu, S.W. (2016) A new river loach from the main channel of the upper Mekong in Yunnan (Cypriniformes: Nemacheilidae). Zootaxa, 4168 (3), 594–600.
https://doi.org/10.11646/zootaxa.4168.3.13
Eschmeyer, W.N., Fricke, R. & van der Laan, R. (2018) Catalog of Fishes: Classification: http://www.calacademy.org/scientists/catalog-of-fishes-classification/. Electronic version (accessed 17 May 2018)
Jamshidi, S., Abdoli, A., Sherafatian, M. & Golzarianpour. K. (2013) Analysis of mitochondrial DNA sequences of Turcinoemacheilus genus (Nemacheilidae; Cypriniformes) in Iran. Iranian Journal of Fisheries Sciences, 12, 592–604.
Kearse, M., Moir, R., Wilson, A., Stones-Havas, S., Cheung, M., Sturrock, S., Buxton, S., Cooper, A., Markowitz, S., Duran, C., Thierer, T., Ashton, B., Mentjies, P. & Drummond, A. (2012) Geneious Basic: an integrated and extendable desktop software platform for the organization and analysis of sequence data. Bioinformatics, 28, 1647–1649.
https://doi.org/10.1093/bioinformatics/bts199
Kottelat, M. (1990) Indochinese nemacheilines: a revision of nemacheiline loaches (Pisces: Cypriniformes) of Thailand, Burma, Laos, Cambodia, and southern Viet Nam. Pfeil, München. 262 pp.
Kottelat, M. (2012) Conspectus cobitidum: an inventory of the loaches of the world (Teleostei: Cypriniformes). Raffles Bulletin of Zoology, Supplement, 26, 1–199.
Liu, H., Tzeng, C.S. & Teng, H.Y. (2002) Sequence variations in the mitochondrial DNA control region and their implications for the phylogeny of the Cypriniformes. Canadian Journal of Zoology, 80, 569–581.
https://doi.org/10.1016/j.gene.2012.07.040
Liu, S., Mayden, R.L., Zhang, J., Yu, D., Tang, Q., Deng, X. & Liu, H. (2012) Phylogenetic relationships of the Cobitoidea (Teleostei: Cypriniformes) inferred from mitochondrial and nuclear genes with analyses of gene evolution. Gene, 508, 60–72. https://doi.org/10.1016/j.gene.2012.07.040
Lokeshwor, Y., Barat, A., Sati, J., Darshan, A., Vishwanath, W. & Mahanta, P.C. (2012) Schistura obliquofascia, a new loach from Uttarakhand, India (Cypriniformes: Nemacheilidae). Zootaxa, 3586, 255–263.
Min, R., Chen, X., Yang, J., Winterbottom, R. & Mayden, R.L. (2012) Phylogenetic relationships of the genus Homatula (Cypriniformes: Nemacheilidae), with special reference to the biogeographic history around the Yunnan-Guizhou Plateau. Zootaxa, 3856, 78–94.
Mirza, M.R., Nalbant, T.T. & Bănărescu, P.M. (1981) A review of the genus Schistura in Pakistan with description of new species and subspecies (Pisces, Cobitidae, Noemacheilinae). Bijdragen tot de Dierkunde, 51, 105–130.
Nylander, J.A. (2004) MrModeltest v2.2. Program distributed by the author. Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden.
Pandey, A., Lakra, W.S., Thapliyal, R.P., Goswami, M., Singh, M. & Malakar, A.K. (2012) Morphological taxonomy and molecular divergence of four balitorid species (subfamily: Nemachelinae) from Central Himalaya, India. Mitochondrial DNA, 23, 239–249.
https://doi.org/10.3109/19401736.2012.674117
Plongsesthee, R., Page, L.M. & Beamish, W. (2011) Schistura aurantiaca, a new species from the Mae Khlong basin, Thailand (Teleostei: Nemacheilidae). Ichthyological Exploration of Freshwaters, 22, 169–178.
Rambaut, A. & Drummond, A.J. (2009) Tracer v1.5. Available from: http://tree.bio.ed.ac.uk/software/tracer/ (Accessed 19 Feb. 2019)
Ronquist, F. & Huelsenbeck, J.P. (2003) MrBayes 3: Bayesian phylogenetic inference under mixed models. Bioinformatics, 19, 1572–1574.
https://doi.org/10.1093/bioinformatics/btg180
Saitoh, K., Sado, T., Mayden, R.L., Hanzawa, N., Nakamura, K., Nishida, M., & Miya, M. (2006) Mitogenomic evolution and interrelationships of the Cypriniformes (Actinopterygii: Ostariophysi): the first evidence toward resolution of the higher-level relationships of the world’s largest freshwater fish clade based on 59 whole mitogenome sequences. Journal of Molecular Evolution, 63, 826–841.
https://doi.org/10.1007/s00239-005-0293-y
Sakai, T., Mihara, M., Shitara, H., Yonekawa, H., Hosoya, K. & Miyazaki, J. (2003) Phylogenetic relationships and intraspecific variations of loaches of the genus Lefua (Balitoridae, Cypriniformes). Zoological Science, 20, 501–514.
https://doi.org/10.2108/zsj.20.501
Sayyadzadeh, G., Eagderi, S. & Esmaeili, H.R. (2016) A new loach of the genus Oxynoemacheilus from the Tigris River drainage and its phylogenetic relationships among the nemacheilid fishes (Teleostei: Nemacheilidae) in the Middle East based on mtDNA COI sequences. Iranian Journal of Ichthyology 3, 4, 236–250.
Sember, A., Bohlen, J., Šlechtová, V., Altmonov, M., Symonov, R. & Ráb, P. (2015) Karyotype differentiation in 19 species of river loach fishes (Nemacheilidae, Teleostei): extensive variability associated with rDNA and heterochromatin distribution and its phylogenetic and ecological interpretation. BMC Evolutionary Biology, 15, 251, 1–22.
https://doi.org/10.1186/s12862-015-0532-9Singer, R.A. & Page, L.M. (2015) Revision of the zipper loaches, Acanthocobitis and Paracanthocobitis (Teleostei: Nemacheilidae), with descriptions of five new species. Copeia, 2015, 378–401.
https://doi.org/10.1643/CI-13-128
Singer, R.A., Pfeiffer, J.M. & Page, L.M. (2017) A revision of the Paracanthocobitis zonalternans (Cypriniformes: Nemacheilidae) species complex with descriptions of three new species. Zootaxa, 4324, 085–107.
Siva, C., Kumar, R., Sharma, L., Laskar, M.A., Sumer, S., Barat, A. & Sahoo, P.K. (2017) The complete mitochondrial genome of a stream loach (Schistura reticulofasciata) and its phylogeny. Conservation Genetics Resources. (2017)
https://doi.org/10.1007/s12686-017-0941-8
Šlechtová, V., Bohlen, J. & Tan, H.H. (2007) Families of Cobitoidea (Teleostei; Cypriniformes) as revealed from nuclear genetic data and the position of the mysterious genera Barbucca, Psilorhynchus, Serpenticobitis and Vaillantella. Molecular Phylogenetics and Evolution, 44, 1358–1365.
https://doi.org/10.1016/j.ympev.2007.02.019
Stöver, B.C. & Müller, K.F. (2010) TreeGraph 2: combining and visualizing evidence from different phylogenetic analyses. BMC Bioinformatics, 11, 7.
https://doi.org/10.1186/1471-2105-11-7
Sun, Q., Wang, D., Wei, Q. & Wu, J. (2016) The complete mitochrondrial genome of Triplophysa robusta (Teleostei, Cypriniformes: Cobitidae). Mitochondrial DNA Part A, 27, 3, 1744–1745.
https://doi.org/10.3109/19401736.2014.961150
Swofford, D.L. (2002) PAUP*: Phylogenetic analysis using parsimony (*and other methods), Version 4. Sinauer Associates, Sunderland, Massachusetts.
Tang, Q., Liu, H., Mayden, R. & Xiong, B. (2006) Comparison of evolutionary rates in the mitochondrial DNA cytochrome b gene and control region and their implications for phylogeny of the Cobitoidea (Teleostei: Cypriniformes). Molecular Phylogenetics and Evolution, 39, 347–357.
https://doi.org/10.1016/j.ympev.2005.08.007
Unmack, P.J., Dowling, T.E., Laitinen, N.J., Secor, C.L., Mayden, R.L., Shiozawa, D.K. & Smith, G.R. (2014) Influence of introgression and geological processes on phylogenetic relationships of western North American mountain suckers (Pantosteus, Catostomidae). PLoS ONE, 9 (3), e90061.
https://doi.org/10.1371/journal.pone.0090061