New record of the Sewing Needle Zipper Loach Paracanthocobitis linypha Singer & Page, 2015 (Teleostei: Cypriniformes: Nemacheilidae) from the Chindwin drainage of Manipur, India

Paracanthocobitis linypha Singer & Page, a freshwater nemacheiline zipper loach, is reported for the first time from the Lokchao River of Manipur (headwaters of Chindwin drainage), in northeastern India. The species is diagnosed in having an incomplete lateral line, flank with 10–14 thin dark bars, long bars occasionally alternating with short bars extending up to about lateral mid-line, interspaces broader than bar width. Morphometric and meristic data of the examined specimens were compared with the original description to validate the species identity.

Abundance and Distribution, Growth Pattern, Sex Ratio and Gonadosomatic Index (GSI) of Liza falcipinnis (Valenciennes, 1836) from Ojo Axis of Badagry Creeks, Lagos, Nigeria

A study on seasonal abundance, morphometric and meristic data, growth pattern, condition factor, sex ratio and gonadosomatic index of Liza falcipinnis (Valenciennes, 1836) from the Ojo axis of Badagry creek, Nigeria was conducted from May 2019 to March 2020. A total of 1012 species were randomly selected, having 499 females and 513 males. The length frequency analysis and length-weight relationships (LWR) were determined. Sex ratio was determined by Chi-square analysis. The results showed that morphometric data are: 0.5 - 2.5 mm for ED, 2.1 - 12 mm for HL, 1.7 - 8.1 mm for HD, 2.5 - 11.7 for BD, 2.6 - 233.3 mm for TL and 9.23 - 1006 g for BW for the combined sexes. The slope (b) shows an allometric growth pattern. The intercept ‘a’ and slope ‘b’ of the LWR (LogW = a + bLogL) were Log W=15.39+ 0.34 LogL (r= 0.54) for combined sexes, Log W= 12.49+ 0.02 log L (r= 0.38) for males and Log W= 18.23+ 0.01 log L (r=0.16) for females.The length frequency distribution indicated that species were dominated by two year classes (Ages 1 and 2). Condition factors were generally low. The values ranged between 0.68 - 0.85 for combined sexes. The gonadosomatic index for female was highest in August, 2019 (17.77%) with Mean±SD of 2.88±0.75; which indicated the peak of spawning period in the study area.Sex ratio difference was significant (P<0.05). Sexual differences were significant; the females are phenotypically larger than the male.

Validating the presence of Spanish Flag, Gonioplectrus hispanus (Cuvier, 1828) (Perciformes, Serranidae), from the south-western Gulf of Mexico

We report the presence of Gonioplectrus hispanus (Cuvier, 1828) in Mexican waters of the Gulf of Mexico. Four specimens (198&ndash;224 mm standard length) were caught at two locations south of Veracruz. These records increases the number of species in the family Serranidae for Mexico to 113. We include morphometry and meristic data of our specimens.

Cabo Verde giant gecko: how many units for conservation?

Tarentola gigas (Bocage, 1875) is the largest gecko living in the Cabo Verde Archipelago. It is subdivided into two subspecies, one confined to the Branco Islet, Tarentola gigas brancoensis (Schleich, 1984), and another to the Raso Islet, Tarentola gigas gigas (Bocage, 1875). These islets were classified as Integral Natural Reserves and further studies on the species are needed to outline more assertive conservation measures. Thus, this study aims to integrate for the first time genetic, morphometric and meristic data to test if there are significant differences between these two taxonomical groups that would support the subspecific designation. The results indicated that they are two closely related subspecies, with some visible differences in size and shape, possibly related to diet, habitat conditions or drift. Given the conservation status of the species, this should be further investigated, aiming an adequate management of these two evolutionarily significant units.

Early ontogeny of Pimelodus blochii Valenciennes, 1840 (Siluriformes: Pimelodidae): Neotropical catfish

Larval ontogeny of the long-whiskered catfish Pimelodus blochii Valenciennes, 1840 is described, providing useful characters for identification and determining the growth pattern throughout its development. Eighty-nine larvae classified in three stages (preflexion, flexion and postflexion) and 30 juveniles were analyzed, totaling 119 individuals. The specimens were collected monthly from January 2013 to May 2019 in the lower Amazon river. A suite of morphological, morphometric, and meristic data was used to describe the stages of development. Three analytical regression models were used: simple linear, quadratic and piecewise regressions. The larvae are characterized by small to moderate eyes, subinferior mouth, and long barbels (maxillary larger than the mental barbels), triangular-shaped adipose fin, and the final part of the intestine reaching half the body. Pigmentation consists of dendritic chromatophores distributed irregularly in the body, ventral region and head, intensifying in the flanks and dorsal region throughout development. The total number of myomeres has a mode of 42 muscle bundles, ranging from 40 to 42 (15 to 16 pre-and 25 to 26 post-anal) and the number of fin segments corresponded to: pectoral = I + 9, pelvic = 6, dorsal = I + 6 and anal = 11–12. All body variables showed discontinuous isometric growth, indicating a deceleration in the structural modeling of the body, between the flexion/post-flexion stages and acceleration in post-flexion/early juvenile period. Precisely when the formation of the fin rays, muscles and organs of the digestive system and ossification are observed, suggesting low morphological variation during ontogenetic development. Pimelodus blochii differs from other congeneric species in the lower Amazon river by meristic characters, which helps to correctly identify individuals in early stages of development.

Morphological characterization of natural populations of Sarotherodon galilaeus (Linnaeus, 1758) from three selected reservoirs in South Western, Nigeria

Morphological characterization of Sarotherodon galilaeus (Linnaeus, 1758)from Opa, Asejire and Ero reservoirs in southwest, Nigeria was carried out with a view to determining the morphological heterogeneity or homogeneity among the three different populations and to determine whether there are morphotypes of this species in the selected study areas. Twenty five morphometric measurements and six meristic counts were recorded on 150 specimens; fifty from each reservoir population. Principal Component Analysis (PCA) and Canonical Variate Analysis (CVA) were performed on the morphometric and meristic data using PAST software. All the clusters produced by the PCA and CVA analyses on the morphometric and meristic data overlapped widely; indicating a low level of morphological differentiation among the three populations of Sarotherodon galilaeus. The study concluded that the Sarotherodon galilaeus populations from Opa, Asejire and Ero reservoirs are morphologically similar and phenotypically inseparable. Keywords: Morphometric, Meristic, Morphological differentiation, Reservoirs in south-western Nigeria, Sarotherodon galilaeus

Four new species of Serranochromis (Teleostei: Cichlidae) from the Cuanza and Okavango river systems in Angola, including a preliminary key for the genus

The present study describes Serranochromis alvum n. sp., Serranochromis swartzi n. sp., Serranochromis cuanza n. sp., and Serranochromis cacuchi n. sp. from Angolan tributaries of the Cuanza and Okavango systems in Angola. The presence of four or five scale rows between the posterior margin of the orbit and the ascending arm of the preoperculum, the presence of widely set unicuspid teeth on the jaws, widely separated gill rakers, and anal fins with egg ocelli place these four species in Serranochromis. The Serranochromis described herein are distinguishable based on a combination of morphological and meristic characters, as well as pigmentation patterns. The interorbital width (14.3–15.9 % HL) of S. alvum is narrower than that of S. swartzi (17.6–19.8), S. cuanza (16.3–18.0), and S. cacuchi (20.0–21.7). Moreover, the interorbital width of S. cacuchi is greater than the other three described species. Serranochromis swartzi has a smaller preorbital depth (16.2–18.9 % HL) and snout length (29.6–31.9 % HL) than Serranochromis cuanza (PD 19.1–22.2, SNL 35.2–39.6 % HL). Serranochromis alvum is known only from the type locality at Cuito-Cuanavale at the junction of the Cuito and Cuanavale rivers, tributary to the Okavango River in Angola. Serranochromis swartzi is known only from the type locality in the Cuanza River, Angola. Serranochromis cuanza is restricted to the Cuanza River, below Capanda Dam, Angola, while S. cacuchi is known only from the Cacuchi River, a tributary of the Cuchi-Cubango River in Angola. The limited distribution of all four species and the absence of many congeners suggest, that in addition to previous studies that invoked a lacustrine speciation model, vicariance through drainage isolation seems to have played an important role in driving speciation in this group. The minimum polygon clusters that are formed when the first principal components of the meristic data are plotted against the second sheared principal components of the morphometric data show separation of the four new species.

The variability of morphometric and meristic characteristics of Urmia chub, Petroleuciscus ulanus (G nther, 1899) in the Mahabd-Chai and Godar-Chai rivers, Lake Urmia basin

In this study, for the first time, we provide morphometric and meristic data on Petroleuciscus ulanus from the Lake Urmia basin by comparing them in the populations of the Mahabad-Chai and Godar-Chai rivers. For this purpose, a total of 100 specimens were collected using electrofishing device and cast net during 2014 and 2015. 19 morphometric and 8 meristic traits were measured and counted, respectively. The meristic traits of the two populations showed significant differences in three characters, including branched dorsal and ventral fin rays and lateral line scales (P<0.05). In addition, the morphometric analysis showed significant differences in head length, eye diameter, caudal peduncle length, dorsal fin height and base lengths, pectoral and ventral fin lengths, anal fin base and height lengths (P<0.05). The finding of the current study can help to further studies on the biological features of this endemic species of Iranian inland waters.

The confirmed occurrence of two specimens of Remora remora (Linnaeus, 1758) from Mersin Bay (NE Mediterranean, Turkey)

Remoras attach to sharks, big fish, and sea turtles and continue their lives with these creatures. Kapızlı and Tekeli beaches are located near Göksu Delta and Anamur nesting areas of Caretta caretta. In this study, two Remora individuals were caught with a fishing rod in July, when the ovulation was most intense. The smaller remora individual (33 cm) was caught from the coast of Tekeli with the chicken breast at a depth of 2.5 m, and the larger one (66 cm) with bread at a depth of 1.5 m from Kapızlı beach on 24.07.2020. The two Remora individuals caught were probably attached to the sea turtles. However, probably due to sea turtles going to the beach to lay eggs, Remoras started to free-swimming, and they were caught with the fishing line since they could not be fed. The present study reported that the first occurrence of Remora specimens is probably attached to turtles for Turkey's northeastern Mediterranean coast. Besides, this study is provided some morphometric and meristic data on this species and discussed a probable host of these specimens.

Integrative taxonomy reveals a new species of Neotropical headstanding fish in genus Schizodon (Characiformes: Anostomidae)

Schizodon encompasses approximately 15 species of Neotropical headstanding fishes. Integrative taxonomy, combining molecular and morphometric analyses with traditional taxonomic methods, was used to investigate Schizodon vittatus and its potential new sister species. Molecular differences between the two species in the barcode are greater than intra-specific variation recovered in species of Schizodon, and the two species represent distinct lineages for approximately one million years. The two species are morphologically very similar, and the meristic data showed great overlap. Morphometric analyses also showed overlap among the putative species but indicated differences in caudal-peduncle depth, orbital diameter, and length of anal-fin rays. Color pattern seems to provide a clear diagnostic feature for the two species. Schizodon vittatus usually has four dark brown transversal bars on body, and its sister species has three conspicuous bars, with the fourth, if present, inconspicuous and dorsal to the lateral line. Schizodon vittatus is redescribed based on the type and recently collected specimens, its type locality is revisited, and its known distribution restricted to the Araguaia and Tocantins drainages. The new species, sister to S. vittatus, distributed in the Xingu and Tapajós drainages, is described. A key for the identification of the Amazon clade species of Schizodon is provided.