Length–weight relationships of six species of the genera Cobitis and Sabanejewia (Cobitidae) in Iranian river systems

Length‐weight relationships (LWRs) were estimated for six spined loach species from Iran. Data were collected between 2010 and 2015. These represent the first reports of length–weight data for five of the species (Cobitis avicennae, Cobitis faridpaki, Cobitis keyvani, Sabanejewia aurata and Sabanejewia caspia) while also providing additional data on the remaining species (Cobitis linea). Five of these species are endemic and the remaining S. caspia, is native to the country. Estimated b values obtained for the studied species ranged from 2.381 for S. aurata to 3.411 for C. keyvani.     

Length–weight relationships of three fish species from the Tajan River,Iran

The study describes the length–weight relationships for two Cobitid species, namely Cobitis keyvani and Sabanejewia aurata, plus a Gobiid species, Ponticola gorlap, all from the Tajan River in Mazandaran province, Iran.     

Phylogenetic relationships of nine mullet species (Mugilidae) in the Mediterranean Sea

Phylogenetic relationships among four genera and nine species (Mugil cephalus, Mugil soiuy, Liza ramada, Liza aurata, Liza abu, Liza saliens, Liza carinata, Chelon labrosus, Oedalechilus labeo) of the Mediterranean mullets (Mugilidae) were investigated by means of allozyme electrophoresis using a seven-enzyme system (CK*, GAPDH*, G3PDH*, IDHP*, ME*, MDH*, PGM*) comprising eleven putative loci. The highest genetic divergence was 1.299, detected between M. cephalus and L. aurata and the lowest (0.280) was found between L. carinata and L. saliens. The amount of genetic divergence between the genera Chelon and Oedalechilus did not appear to be high (0.285). In a UPGMA tree, all nine species were grouped in two main branchings. In the first branch, C. labrosus and O. labeo clustered as closest taxa and were sister group to L. ramada. The other four Liza species produced two sub-branching in this group; L. carinata branched together with L. saliens, and L. aurata branched together with L. abu. In the second branch the two species of the genus Mugil, M. cephalus and M. soiuy, clustered together and were clearly isolated from the other three genera.     

Length–weight relationships of six coral reef‐fish species from Chuuk,Federated States of Micronesia

Length–weight relationships (LWR) were estimated for six reef species in Chuuk lagoon (Federated States of Micronesia) captured by commercial fishers. Specimens were sampled opportunistically over a period of 2 months between July and September 2014. Relationships include those for four common species not currently reported in FishBase (Caesio teres, Myripristis adusta, Lethrinus erythracanthus, and Chlorurus frontalis), and for two species with relationships based on just one or two samples (Scarus oviceps, and Plectropomus oligacanthus). While estimates for some species are tentative given limited size‐range sampling, they still present an improvement in the currently available LWRs.     

Molecular Phylogeny of Grey Mullets (Teleostei: Mugilidae) in Greece: Evidence from Sequence Analysis of mtDNA Segments

Mitochondrial DNA sequence analysis has been used to explore genetic differentiation and phylogenetic relationships among five species of the Mugilidae family, Mugil cephalus, Chelon labrosus, Liza aurata, Liza ramada, and Liza saliens. DNA was isolated from samples originating from the Messolongi Lagoon in Greece. Three mtDNA segments (12s rRNA, 16s rRNA, and CO I) were PCR amplified and sequenced. Sequencing analysis revealed that the greatest genetic differentiation was observed between M. cephalus and all the other species studied, while C. labrosus and L. aurata were the closest taxa. Dendrograms obtained by the neighbor-joining method and Bayesian inference analysis exhibited the same topology. According to this topology, M. cephalus is the most distinct species and the remaining taxa are clustered together, with C. labrosus and L. aurata forming a single group. The latter result brings into question the monophyletic origin of the genus Liza.     

Length–weight relationships for 39 species of moray eel from the waters around Taiwan

Length–weight relationships were determined in 39 muraenid species belonging to seven genera collected during 2003–2008 from the waters around Taiwan. Various fishing methods were used to collect both the adult and pre‐adult moray eel specimens. Length–weight relationship records of 28 species are provided for the first time. New maximum size records of six species were also established: 61.2 cm for Gymnothorax monostigma, 88.2 cm for G. niphostigmus, 68.6 cm for G. shaoi, 53.9 cm for G. taiwanensis, 73.2 cm for G. thyrsoideus, and 37.3 cm for U. micropterus.     

Genetic Divergence and Phylogenetic Relationships in Grey Mullets (Teleostei: Mugilidae) Using Allozyme Data

Genetic divergence and phylogenetic relationships among five species of the Mugilidae family (Liza saliens, Liza aurata, Liza ramada, Chelon labrosus, and Mugil cephalus) were investigated, in the present study, on samples taken from Messolongi lagoon in Greece, using allozyme electrophoresis. Ten enzymic systems corresponding to 22 genetic loci were assayed, among which, four were found to be polymorphic in Liza saliens, Liza aurata, and Chelon labrosus, seven in Liza ramada, while only two were polymorphic in Mugil cephalus. Several loci showed different electrophoretic patterns among the species and thus, they can be useful in species taxonomy as diagnostic markers, as well as for further evolutionary studies. It must be underlined that among them the aGPD-2* locus proved to be species-specific, while the other ones can be also used in various combinations for the same purpose. The observed heterozygosity was found to range from 0.020 to 0.051. Allele frequencies of all loci were used to estimate Nei's (1972) genetic distance, which was found to range between 0.249 and 1.171 among the five species studied. UPGMA and NJ trees, obtained by genetic distance matrix methods, as well as, a tree based on the discrete character parsimony analysis were found to exhibit the same topology. Our result show that the three species of the genus Liza are clustered together, Chelon labrosus being closer to the previous clade, while Mugil cephalus being more distinct.     

Genetic divergence and phylogenetic relationships in grey mullets (Teleostei: Mugilidae) based on PCR-RFLP analysis of mtDNA segments

The genetic differentiation and phylogenetic relationships among five species of the Mugilidae family (Mugil cephalus, Chelon labrosus, Liza aurata, Liza ramada, and Liza saliens) were investigated at the mtDNA level, on samples taken from Messolongi lagoon-Greece. RFLP analysis of three PCR-amplified mtDNA gene segments (12s rRNA, 16s rRNA, and CO I) was used. Ten, eight, and nine restriction enzymes were found to have at least one recognition site at 12s rRNA, 16s rRNA, and CO I genes, respectively. Several fragment patterns were revealed to be species-specific, and thus they could be useful in species taxonomy as diagnostic markers, as well as for further evolutionary studies. Seven different haplotypes were detected. The greatest amount of genetic differentiation was observed at the interspecific level, while little variation was revealed at the intraspecific level. The highest values of nucleotide sequence divergence were observed between M. cephalus and all the other species, while the lowest was found between C. labrosus and L. saliens. Dendrograms obtained by the three different methods (UPGMA, Neighbor-Joining, and Dollo parsimony), were found to exhibit in all cases the same topology. According to this, the most distinct species is M. cephalus, while the other species are clustered in two separate groups, the first one containing L. aurata and L. ramada, the other L. saliens and C. labrosus. This last clustering makes the monophyletic origin of the genus Liza questionable.     

Length–weight relationships and length at first maturity for fish species in the upper Miranda River,southern Pantanal wetland,Brazil

Length–weight relationships (LWR) were estimated for 17 species and total length at first maturity (L50) for three species of freshwater fishes from the Miranda River, southern Pantanal, Brazil. The b values were compared for some species in the Paraguay River basin with the northern (Cuiabá River) part of the basin; differences in length–weight relationships were significantly different for Pseudoplatystoma corruscans, P. reticulatum (syn. P. fasciatum). First references on L50 and LWR are presented for two and eight fish species, respectively, as well as the new maximum total length for two species.     

Weight–length relationships for eight species of the family Triglidae discarded on the south coast of Portugal

Gurnards or triglids are medium‐size marine bottom fishes that live in tropical and temperate seas. Four genera (Aspitrigla, Chelidonichthys, Lepidotrigla, Trigla) and eight species are found in the eastern Atlantic. In this study, we report the weight–length relationships for eight species, with 75 specimens of A. cuculus, 45 of C. obscurus, 84 C. gurnardus, 21 C. lucernus, 45 C. lastoviza, 550 L. cavillone, 255 L. dieuzeidei and 40 T. lyra. These triglids were caught by three different methods: crustacean trawl, fish trawl and purse seine off the Algarve coast; all specimens sampled were part of the discards. Samples were obtained from depths ranging between 20 and 540 m, during 27 trips and 86 hauls. To the best knowledge of the authors, this study presents the first reference on weight–length relationships for four fish species from the Algarve coast (southern Portugal).     

Length–weight relationships of six tropical fish species from Chilika Lagoon,India

The length weight relationships (LWRs) of six tropical fish species from Chilika Lagoon, India were studied. Specimens were caught using a wide range of fishing gear operated in the lagoon from January to December 2014. The fresh specimens were measured for total length and weight, then dissected and the sex confirmed. Previously unavailable in FishBase, the detailed LWRs of Daysciaena albida, Eleutheronema tetradactylum, Etroplus suratensis and Mystus gulio are reported for the first time. Maximum total lengths reported for Nematalosa nasus and Osteogeneiosus militaris in this study are new records for these species. The existence of a differential growth between male and female O. militaris was confirmed, which was not known earlier.     

Butyltin compounds in sediment and biota from the lagoon of Bizerte (northern Tunisia): Potential risk for consumers?

Levels of butyltins (BTs) were monitored in sediment samples and in seven fish species (Boops boops, Diplodus sargus, Sarpa salpa, Serranus scriba, Spicara smaris, Trachurus draco, and Trachinus mediterraneus), five bivalve species (Cerastoderma glaucum, Chlamys flexuosa, Mytilus galloprovincialis, Pinna nobilis, and Ruditapes decussatus), two gastropod species (Bolinus brandaris and Hexaplex trunculus), cuttlefish (Sepia officinalis), and shrimp (Penaeus notialis), most of which are commonly consumed in Tunisia. Samples were collected from Bizerte lagoon during March 2012. Average concentrations of total BTs found in sediment and the muscle of fishes, bivalves, gastropods, cuttlefish, and shrimp were 17.7, 11.5, 31.8, 36.9, 8.1, and 9.4 ng Sn g^?1 dw, respectively. The calculation of tolerable average residue levels and non-cancer hazard quotient for tributyltin (TBT) showed that daily exposure of these seafood to TBT is unlikely to cause any deleterious effects to humans, thus indicating that consumers may not be at risk through the inclusion of these species in their regular diet.     

Length–weight relationships of nine fish species from the Tongjiang section of the Songhua River,China

Length–weight relationships were evaluated for nine fish species from the Tongjiang section of the Songhua River in China. A total of 675 fish specimens were collected from 4 May to 29 October 2014. Length–weight relationships for six fish species (Romanogobio tenuicorpus, Leuciscus waleckii, Opsariichthys bidens, Microphysogobio amurensis, Pelteobagrus ussuriensis and Misgurnus mohoity) were new to FishBase in 2015, but the length–weight relationships of P. ussuriensis was studied by Ma in 2015. New data on M. mohoity is offered, and this study also shows new maximum total lengths for three fish species. The r² values ranged from .95 to .99. Values of b varied from 2.504 to 3.471.     

A review of length–weight relationships of fish from the Segura River basin (SE Iberian Peninsula)

We present the relationships between fork length and total weight for 14 fish species from the Segura River basin (southeastern Spain): Barbus sclateri, Chondrostoma polylepis, Gobio lozanoi, Aphanius iberus, Micropterus salmoides, Lepomis gibbosus, Carassius auratus auratus, Cyprinus carpio carpio, Sander lucioperca, Gambusia holbrooki, Liza ramado, Mugil cephalus, Atherina boyeri and Pomatoschistus marmoratus. Significant length–weight relationships were found for all species. The values of the exponent b of the length–weight relationships ranged from 3.82 for Sander lucioperca to 2.59 for Micropterus salmoides.     

Length–weight relationships for selected fish species from a coastal lagoon influenced by freshwater seeps: Yucatan peninsula,Mexico

The present work analyzes the relationship between length and weight for 28 fish species belonging to 16 families in Celestun lagoon, a natural marine reserve located in southeast Mexico that is influenced by freshwater seeps. With interrupted periods, a total of 14 846 specimens were collected from 1990 to 2006. The most abundant species were Eucinostomus argenteus, Eucinostomus gula, Anchoa mitchilli and Lagodon rhomboides. Exponents varied around b = 3.17 at P < 0.001, indicating a preference for isometric relationships. This study presents the first estimation of LWR for four species (Menidia colei, Lucania parva, Floridichthys polyommus, Garmanella pulchra) and the maximum length record for F. polyommus (19.5 cm standard length) that is greater than previously recorded.     

Length–weight and length–length relationships of three Clupeonella species (Clupeidae) from the Caspian Sea

This study investigated length–weight and length–length relationships of three Clupeonella species: C. caspia, C. engrauliformis and C. grimmi captured in the southern Caspian Sea, Iran. Using a lantern net, 206 specimens were collected from July to August 2016. Presented for two of the species are the length–weight and the length–length relationships as well as the first reference on length–weight and length–length relationships for C. caspia in its distribution range.     

Length–weight relationships for seven freshwater fishes caught in Kemer reservoir, Turkey

Length–weight relationships (LWR) were estimated for Acanthobrama mirabilis, Barbus pectoralis, Chondrostoma meandrense, Capoeta bergamae, Silurus glanis, Petroleuciscus smyrnaeus and Cyprinus carpio from the Kemer reservoir in western Anatolia, Turkey. This study is the first reference on length–weight parameters for five of these species.     

Length–weight and length–length relationships of four native fish species from the Yalong River,China

Length‐weight and length‐length relationships were estimated for four native fish species from the Yalong River and its tributaries, China. A total of 976 specimens were collected monthly using trap nets and electric fishing in May 2013 and July 2015 to February 2016. This study presents the first references on LWRs (length–weight relationships) and LLRs (length–length relationships) for three species (Gymnocypris firmispinatus, Paracobitis variegatus and Euchiloglanis kishinouyei). Moreover, maturation length, absolute fecundity and predominant food items for the four species were also described in the study.     

Length-weight relationships of six tropical estuarine fish species from Pulicat lagoon,India

Length–weight relationships (LWRs) of six finfish species under two families of the order Perciformes collected from Pulicat lagoon (India) are presented in this study. The fish specimens were collected weekly from the catches of shore seine net (with a mesh size of 50mm at the main webbing and 10 mm at the cod end) operated in the lagoon at an average depth of 2.5 m by the local fishermen during the period from July 2018 to April 2019. This study reports the LWRs for five gobiid and one siganid fish species which have no earlier reports on LWRs. The calculated ‘b’ value ranged from 3.538 (Favonigobius reichei) to 2.677 (Oxyurichthys microlepis) and ‘a’ value varied from 0.0041 (Favonigobius reichei) to 0.0199 (Acentrogobius cyanomos). This study also reports the new maximum total length (TL_max) for the gobiid fish species Oxyurichthys microlepis.