Length–weight relationships for five fishes in the Nmai Hka River,Myanmar

Length–weight relationships (LWRs) were investigated for five fish species occurring in the Nmai Hka River. Fish were collected monthly from five sites between January and May 2009, using five gill nets in the main river and electrofishing in tributaries. The results of LWRs for Bangana devdevi (Hora, 1936), Garra qiaojiensis Wu & Yao, 1977, Amblypharyngodon atkinsonii (Blyth, 1860), Schizothorax meridionalis (Tsao, 1964) and Mystus pulcher (Chaudhuri, 1911) provide basic data useful in fisheries science. All values of parameter b ranging from 2.89 for Bangana devdevi (Hora, 1936) and 3.47 for Garra qiaojiensis Wu & Yao, 1977(in all cases r² > .951).A new total length has been recorded for Garra qiaojiensis Wu & Yao, 1977 when comparing with records given in the international electronic databank FishBase (Froese & Pauly, 2017).     

Length‐weight relationships for nine fishes in the Nujiang River,Southwest of China

Length‐weight relationships (LWRs) were determined for nine fish species occurring in the Nujiang River. Fish were collected using gill nets, including two nets of 1.0 m depth (100 m long; mesh size 0.5 cm), two nets of 1.0 m depth (150 m long; mesh size 2.0 cm) and two nets reaching 1.5 m depth (mesh size 6.0 cm). Gill nets were set over night including different habitats (riffles and pools, vegetated and non vegetated zones) from four sections in July of the following 2 years: 2004 and 2008. The LWRs presented here include for all nine studied species (Pseudexostoma brachysoma Chu, 1979, Creteuchiloglanis gongshanensis [Chu, 1981], Glyptothorax zanaensis Wu, He & Chu, 1981, Glyptothorax dorsalis Vinciguerra, 1890, and Glyptothorax trilineatus Blyth, 1860, Schizothorax gongshanensis Tsao, 1964, Schizothorax meridionalis Tsao, 1964, Placocheilus cryptonemus Cui & Li, 1984, and Schistura longa [Zhu, 1982]), and new maximum standard length of four species not yet reported in the literature.     

Length‐weight relationships of eleven fish species from the middle reaches of Jinsha River,southwest China

Length‐weight relationships (LWRs) were determined for eleven endemic fish species [Coreius guichenoti (Sauvage & Dabry de Thiersant, 1874), Glyptothorax sinensis (Regan, 1908), Leptobotia elongata (Bleeker, 1870), Leptobotia taeniops (Sauvage, 1878), Pseudobagrus crassilabris (Günther, 1864), Rhinogobio ventralis (Sauvage & Dabry de Thiersant, 1874), Saurogobio dabryi (Bleeker, 1871), Schizothorax chongi (Fang, 1936), Schizothorax kozlovi (Nikolskii, 1903), Schizothorax prenanti (Tchang, 1930) and Schizothorax wangchiachii (Fang, 1936)] from the middle reaches of the Jinsha River in southwest China. Samples were obtained between May 2004 and July 2013 using various types of fishing gear and electroshock fishing techniques. For each species, the sample size, length range, weight range, LWR, 95% confidence intervals of a and b, and coefficient of correlation were determined. Prior to this study, the LWRs for four species (P. crassilabris, S. chongi, S. kozlovi and S. prenanti) were unknown.     

Length–weight relationships for 15 fish species from the Three Gorges Reservoir

The length–weight relationships (LWRs) for 15 fish species from the Three Gorges Reservoir (TGR) were described in this paper. Specimens were collected using gill nets (mesh size: 6, 8, 10, 12 cm), cage net (mesh size: 1 cm), benthic fyke net (mesh size: 1 cm), hook longlines (80 m long, 3 barbless hooks per meter line) and electrofishing (power: 1,500 w; distance of electrodes: 1–2 m; water depth: 0.2–1.0 m; water area: 1–2 m²; catch by dip net [mesh size: 0.4 cm]) at four sections of the TGR, monthly in June–August and October–November in 2017 and 2018. The first LWR reference for Zacco acutipinnis (Bleeker, 1871), Discogobio brachyphysallidos Huang, 1989, Squalidus nitens (Günther, 1873), Leptobotia pellegrini Fang, 1936, Sinibotia reevesae (Chang, 1944), Pseudobagrus tenuifurcatus (Nichols, 1931), Pseudobagrus medianalis (Regan, 1904), Liobagrus marginatoides (Wu, 1930), Glyptothorax fokiensis (Rendahl, 1925), and Ctenogobius szechuanensis (Liu, 1940) and new maximum total length for 12 species are provided.     

Length–weight relationships of three schizothoracinae fish species from the Niyang River,a branch of the Yarlung Zangbo River,Tibet, China

The focus was on the length–weight relationships of three schizothoracinae species endemic to Tibet, including Schizothorax oconnori Lloyd, 1908, Ptychobarbus dipogon (Regan, 1905) and Schizopygopsis younghusbandi Regan, 1905, all of which are characterized by slow growth, late maturation and vulnerability to the environment (Ma et al., 2010, 2012; Duan et al., 2014). Among them, Schizothorax oconnori is an endangered fish and listed in the China species Red List (Wang and Xie, 2004, 2009). Samples were obtained by drift net fishing (mesh size 2 cm × 3 cm; 50 m net length) in November 2008. The r² value was 0.94, 0.97, 0.98 and the b value 3.51, 3.12, 3.16, representing Schizothorax oconnori, Ptychobarbus dipogon, and Schizopygopsis younghusbandi, respectively.     

Length–weight relationships for four fish species from lower stretch of River Ganga,India

Length‐weight relationships (LWRs) for four fish species from the River Ganga (India) is presented. Sampling was conducted in the lower stretch of the river (Buxar: 25°33′43.90″N and 83°56′3.10″E to Freserganj: 21°35′40.58″N and 88°15′28.92″E) on tri‐monthly basis from September 2016 to December 2017. Specimens were caught in gill nets (mesh, 18–68 mm), cast nets (mesh, 12–14 mm), seine nets (mesh, 12–14 mm) and various traditional traps those were put over night and lifted in early morning. Total length and wet body weight of fish were measured to the nearest 0.1 cm and 0.01 g by a digital caliper and electronic balance respectively. From LWRs, the estimated b values were found to be 2.88 (Pisodonophis boro) to 3.17 (Gagata sexualis) whereas a value ranged from 0.001 (Pisodonophis boro) to 0.009 (Botia lohachata). As per FishBase, the species Gagata sexualis and Botia lohachata had new TLmax reported for LWR estimation.     

Length–weight relationships of four fish species from the MoTuo reach of the Yarlung Zangbo River,southwest China

Length–weight relationships (LWRs) were evaluated for four fish species from the MoTuo reach of the Yarlung Zangbo River, southwest China: Exostoma labiatum (McClelland, 1842), Schizothorax curvilabiatus (Wu & Tsao, 1992), Nemacheilus subfusca (McClelland, 1839), and Garra kempi Hora, 1921. The a values ranged from 0.0094 (Schizothorax curvilabiatus) to 0.0151 (Exostoma labiatum), b values from 2.698 (Exostoma labiatum) to 2.974 (Schizothorax curvilabiatus), and r² values from 0.976 (Nemacheilus subfusca) to 0.995 (Schizothorax curvilabiatus). A total of 427 fish specimens were collected by electrofishing in April 2015, with LWRs previously unknown to FishBase for four of the species. New maximum lengths are recorded in FishBase for three of these species: Schizothorax curvilabiatus, Nemacheilus subfusca, and Garra kempi.     

Length–weight relationships of three small fish species caught in the Yarlung Zangbo River basin,China

Length–weight relationships (LWRs) were determined for three small fish species, Glaridoglanis andersonii (Day, 1870), Glyptosternum maculatum (Regan, 1905) and Pseudecheneis sulcatus (Mc‐Clelland, 1842) from the Yarlung Zangbo River basin, China. A total of 285 specimens were collected from the Yarlung Zangbo River in May and October 2017(frequency of sampling during the study period: once per month).The specimens were caught with fishing gear including drifting gillnets (nets: 10 × 1.0 m; mesh size: 3.0 cm) and shrimp cages (nets: 4.0 × 0.5 × 0.4 m; mesh size: 0.5 cm).     

Length–weight and length–length relationships of three fish species from the Yarlung Zangbo River in Tibet,China

Length–weight relationships and length–length were evaluated for three fish species (Schizopygopsis younghusbandi Regan, 1905; Ptychobarbus dipogon Regan, 1905 and Oxygymnocypris stewartii Lloyd, 1908) from the Yarlung Zangbo River in Tibet. Specimens were captured monthly using floating gillnets (mesh size 7.5 cm), bottom gillnets (mesh size 6.5 cm), and trap nets (mesh size 1.5 mm) from August 2008 to August 2009, March to August 2012, and March to April 2013. Regression coefficient (b) values of length–weight relationships (LWRs) ranged from 3.045 for P. dipogon to 3.193 for O. stewartii, whereas the a values ranged from 0.0040 to 0.0168 for O. stewartii and P. dipogon, respectively.     

Length–weight relationships of four small fish species caught in the Heishui River,China

In the present paper the length–weight relationships (LWRs) were determined for Jinshaia sinensis Sauvage & Dabry de Thiersant, 1874; Triplophysa anterodorsalis Zhu & Cao, 1989; Liobagrus marginatus Günther, 1892; and Glyptothorax sinensis Regan, 1908 caught in the Heishui River in July 2014. The specimens were caught with fishing gear including drifting gillnets (mesh size 4 cm) and shrimp cages. This paper provides new data on LWRs for FishBase.     

Length‐weight relationships of three cyprinid fish species from southwestern China

Length–weight relationships (LWRs) were determined for three cyprinid fish species [Acrossocheilus yunnanensis (Regan, 1904), Onychostoma simum (Sauvage & Dabry de Thiersant, 1874) and Spinibarbus sinensis (Bleeker, 1871)] from southwestern China. Samples were obtained with various fishing gear (set nets, drift gill nets, fish cages, hook and electrofishing). Prior to this study, the LWRs for these three species (A. yunnanensis, O. simum and S. sinensis) were unknown.     

Re-validation of Gonorhynchus adiscus and G. diplochilus (Teleostei: Cyprinidae) using morphological and molecular data

Small and silvery cyprinid species from eastern Iran which are usually known as Crossocheilus latius are reviewed based on morphological and molecular characters of the mtDNA COI barcode region. We demonstrate that fishes which had been identified as Crossocheilus Kuhl & van Hasselt, 1823 in Iran actually belong to the genus Gonorhynchus McClelland, 1838 with two species: G. adiscus (Annandale, 1919) and G. diplochilus (Heckel, 1838), which are rediagnosed here. Both species are well distinguished by gill raker counts, number of scales between anus and anal fin, barbel size and minimum body depth. G. adiscus and G. diplochilus are also distinguished by molecular characters of the mtDNA COI barcode region. Both species are phylogenetically close to Gonorhynchus latius (Hamilton, 1822) which is restricted to India, Nepal and Bangladesh and to G. burmanicus (Hora, 1936), restricted to India and Myanmar. All of these four related taxa are phylogenetically closer to the genus Garra than the genus Crossocheilus (restricted to south-east Asia).     

Length–weight relationships of two schizothoracinae fish species from the Maquan River,the upper reaches of the Yarlung Zangbo River,Tibet, China

Length‐weight relationships (LWRs) were determined for two endemic fish species from the Maquan River, the upper of the Yarlung Zangbo River: (Ptychobarbus dipogon Regan, 1905, Schizothorax waltoni Regan, 1905). All the specimens were collected between May and September of 2014. Length–weight relationships for these two fish species were determined for the first time, and new maximum body weights were recorded for these two species. These results will be useful for fishery research, management and conservation of the Yarlung Zangbo River.     

Length-weight and length-length relationships of three fish species from the lower Yalong River,China

Length-weight relationships (LWRs) and length-length relationships (LLRs) were evaluated for three endemic fish species sampled from the lower Yalong River and its biggest tributary (the Anning River), in China. Specimens were captured using set gillnet (mesh size 4 cm) and backpack electro-fishing (power output 400 W, depth fished 1 m, area covered 3 m²) from June to July 2018. LWRs and LLRs are presented for the following species (Sinogastromyzon sichangensis, Micropercops swinhonis and Percocypris pingi).     

Length‐weight relationships of three gobiid species (Perciformes: Gobiidae) along the Iranian intertidal coast of the Persian Gulf and Makran Sea

Length weight relationships (LWRs) were estimated for three gobiid species, Bathygobius meggitti(Hora & Mukerji, 1936), Acentrogobius dayi Koumans, 1941 and Cryptocentroides arabicus(Gmelin, 1789) (Perciformes: Gobiidae) collected from 13 localities of the Iranian intertidal coast of the Persian Gulf and Makran Sea in seven times from November 2015 to September 2017 using a hand net with mesh size 1.30 mm. The b values showed significant differences between males and females of all species except the C. arabicus. Bailey's t test revealed that b value significantly deviated from the expected cube value of 3 in three species.     

Length‐weight relationships of three fish species from the Jatinga River (Barak drainage) in Assam,India

The present study reports the Length‐Weight relationships of three freshwater fish species, Amblyceps laticeps (McClelland, 1842), Danio dangila (Hamilton, 1822) and Lepidocephalichthys berdmorei (Blyth, 1860), based on monthly collections between November 2016 and October 2017. Fishes were collected from selected sampling sites along the Jatinga River (a tributary of the Barak River drainage) using cast nets (2.5 m; mesh size: 1.0–1.5 cm) and electrofishing device (Safari Surveyor, 12 V 7 amp). Estimated b values were 2.78 for A. laticeps, 3.19 for D. dangila and 2.92 for L. berdmorei respectively.     

Length–weight relationships of three fish species from the Tibet reach of the Lancang River,China

Length‐weight relationships (LWRs) were determined for three fish species, Schizothorax lantsangensis (Tsao, 1964), Schizothorax lissolabiatus (Tsao, 1964) and Schizopygopsis anteroventris (Wu & Tsao, 1989), from the Tibet reach of the Lancang River, China (N 29°06′–31°30′, E 96°57′–98°38′). Specimens were collected in April and September 2017. The specimens were caught with drifting gillnets (mesh size 2.5 cm and 7.0 cm). The b values of these three fish species ranged from 2.974 to 3.075. The high r² values (all > .980) indicate that these relationships will be appropriate for use in fisheries management of these species.     

Length‐weight relationships of four fish species from the Yellow River,China

Length‐weight relationships (LWRs) were estimated for four fish species [Schizopygopsis anteroventris Wu & Tsao, 1989, Schizothorax lissolabiatus Tsao, 1964, Triplophysa markehenensis (Zhu & Wu, 1981) and Triplophysa siluroides (Herzenstein, 1888)] from the Yellow River. Samples were collected seasonally from August 2016 to October 2017, using various fishing gears [set nets (mesh: 1.5 cm × 2.0 cm), hook, drift gill nets (mesh: 1.0 cm × 2.0 cm × 3.0 cm) and electro fishing]. Four new maximum standard length were recorded for S. anteroventris, S. lissolabiatus, T. markehenensis and T. siluroides.     

Length‐weight relationship and relative condition factor of five indigenous fish species from Torsa River,West Bengal,India

Length‐weight relationships (LWRs) for five indigenous fish species under five genera and two families, namely Cyprinion semiplotum (McClelland, 1839), Barilius barna (Hamilton, 1822), Barilius barila (Hamilton, 1822), Gagata sexualis Tilak, 1970 and Pseudolaguvia shawi (Hora, 1921) were studied from Torsa River in West Bengal, India. Sampling was done at quarterly intervals from November, 2015 to December, 2016 and a total of 701 fish specimens were collected using cast nets (mesh size of 15–20 mm), gill nets (mesh size 20–35 mm) and bamboo traps. In the present study, b value ranges from 2.686 to 3.268. LWRs for these fish species (except P. shawi) have not been reported in FishBase. A new maximum length has been recorded for P. Shawi and G. sexualis. The relative condition factor (Kn) values was found to range from 1.004 to 1.028.     

Length‐weight and length‐length relationships of four small fishes from the Atrai River,Dinajpur, Bangladesh

Length‐weight (LWRs) and length‐length relationships (LLRs) were determined for four fish species collected from the Atari River in Dinajpur of Bangladesh. Sampling took place monthly between January and June 2016, using seine nets of commercial fishermen (mesh size 4 mm). In LWRs (r² > .927, p < .05), slope (b) was estimated as 3.191, 2.992, 3.217 and 3.109 for Acanthocobitis botia, Botia lohachata, Canthophrys gongota and Chanda nama, respectively. In LLRs (r² > .812, p < .05), lengths i.e. TL, SL, HL and FL were highly correlated. The present study on these species would be the baseline for FishBase dataset.