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In the welcome circumstance that species believed extinct are rediscovered, it is often the case that biological knowledge acquired before the presumed extinction is limited. Efforts to address these knowledge gaps, in particular to assess the taxonomic integrity and conservation status of such species, can be hampered by a lack of genetic data and scarcity of samples in museum collections. Here, we present a proof‐of‐concept case study based on a multidisciplinary data evaluation approach to tackle such problems. The approach was developed after the rediscovery, 40 years after its presumed extinction, of the enigmatic Lake Constance deep‐water charr Salvelinus profundus. Targeted surveys led to the capture of further species and additional sympatric normal charr, Salvelinus cf. umbla. Since the lake had been subject to massive stocking in the past, an evaluation of the genetic integrity of both extant forms was called for in order to assess possible introgression. A two‐step genomic approach was developed based on restriction site associated DNA (RAD). Diagnostic population genomic (single nucleotide polymorphism [SNP]) data were harvested from contemporary samples and used for RNA bait design to perform target capture in DNA libraries of archival scale material, enabling a comparison between extant and historic samples. Furthermore, life history traits and morphological data for both extant forms were gathered and compared with historical data from the past 60–120 years. While extant deep‐water charr matched historical deep‐water specimens in body shape, gill raker count, and growth rates, significant differences were discovered between historical and extant normal charr. These resulted were supported by genomic analyses of contemporary samples, revealing the two extant forms to be highly divergent. The results of population assignment tests suggest that the endemic deep‐water charr persisted in Lake Constance during the eutrophic phase, but not one of the historical genomic samples could be assigned to the extant normal charr taxon. Stocking with non‐endemic charr seems to be the most likely reason for these changes. This proof‐of‐concept study presents a multidisciplinary data evaluation approach that simultaneously tests population genomic integrity and addresses some of the conservation issues arising from rediscovery of a species characterized by limited data availability. [ABSTRACT FROM AUTHOR]

Paragobiocichla, new genus, is established for Gobiochromis irvinei Trewavas, 1943, a rheophilic cichlid fish from the Volta River drainage in Ghana and Burkina Faso. It had previously been placed in the genus Stentocranus Boulenger, 1899 (synonyma Leptotilapia Pellegrin, 1928 and Gobiochromis Poll, 1939), which otherwise contains only members endemic to the Congo River basin. However, it is distinguished from Steatocranus by having cycloid scales on the opercle (vs. none in Steatocranus) and by 11-13 gill rakers on the first arch (vs. 4-10 in Steatocranus). [ABSTRACT FROM AUTHOR]

The article discusses the discovery of a new haplochromine cichlid species from the Great Ruaha River drainage in the Rufiji basin of Tanzania in 2014. Topics covered include the materials and methods used in the study which involved the morphological comparisons of 169 specimens of rheophilic haplochromine cichlid specimens, the taxonomy of the species, and its differential diagnosis.

The article focuses on the first record of the Ponto-Caspian racer goby Babka gymnotrachelus from a Danube backwater near the city of Regensburg, Germany and from the main channel near the village of Mariaposching. The previously reported four invasive benthophiline freshwater gobies from the Lower Rhine and Upper Danube in Germany and Austria are given. The taxonomy of Babka gymnotrachelus is discussed.

The article describes the species of Liopropoma emanueli from the Cape Verde Islands. It is similar to a Liopropoma from São Tomé Island and from Brazil. It differs from all described Liopropoma species because of the dorsal fin that is clearly divided, more than 50 lateral line scales and numerous thin yellow lines on a pink body. The taxonomy of Liopropoma emanueli is discussed including the types, diagnosis and etymology.

The article presents a study on the Tilapia species flock of Lake Ejagham in Western Cameroon. The researchers used a digital caliper to take point-to-point measurements on the left side of the specimens, after which they used the statistical program PAST 1.98 to calculate the principal component analysis (PCA) of log-transformed morphometric data. They found that the PCA run of morphometric data of the subgenus Coptodon identified 14 taxa as discernible from Lake Ejagham. They also discussed the differences between two phenotypes of Tilapia fusiforme.

The article presents a study which examined the morphological structure and characteristics of the Gymnocephalus (G.) ambriaelacus, a new species of ruffe from Lake Ammersee in southern Germany. A phylogenetic analysis of both nuclear and mitochondrial sequence data of the new species were discussed by a unique nuclear LdhA6 intron haplotype. The ruffe of Lake Ammersee with G. cernua and G. baloni material were morphometrically and genetically compared from a wide variety of habitats and drainages. Results show that the landmark-based geometric morphometric approach using principal components analysis (PCA) based on the partial warp scores of three lake populations of G. cernua and new species were different despite similarity of ecological conditions influencing body shape.