Molecular phylogeny and speciation patterns in host-specific monogeneans (Cichlidogyrus,Dactylogyridae) parasitizing cichlid fishes (Cichliformes,Cichlidae) in Lake Tanganyika

Cichlidogyrus (including Scutogyrus) is the most speciose dactylogyridean monogenean genus known from African and Levantine cichlid fishes (Cichlidae). While its taxonomy is well established, little is known about the phylogenetic relationships and evolutionary history of this ectoparasite, especially from hosts belonging to one of the most impressive vertebrate radiations, the cichlid fishes from the East African Great Lakes and surrounding hydrological systems. Phylogenetic inference based on DNA sequences of the nuclear 18S, internal transcribed spacer 1 and 28S rDNA genes revealed that Cichlidogyrus parasitizing mainly West African cichlid tribes is paraphyletic with respect to species parasitizing hosts belonging to the East African cichlid radiation, which constitute a well-supported monophylum. Members of Cichlidogyrus from tylochromine and oreochromine hosts that colonised Lake Tanganyika only recently, cluster with their non-Lake Tanganyika relatives, indicating that they colonised Lake Tanganyika with their current host species, and did not jump over from any of the many cichlid species already present in the lake. The diversification of Cichlidogyrus in Lake Tanganyika seems to be driven by failure to diverge in old lineages of cichlids, cospeciation in more recently evolved ones, and host switching followed by parasite duplication at the level of the various host tribes. Evaluation of host specificity and structural evolution of haptoral and reproductive organs in Lake Tanganyika Cichlidogyrus revealed that strict specialist species together with larval hook size represent the ancestral state of haptor configuration, suggesting that members of Cichlidogyrus in this system evolved from a very simple form to a more complex one similarly to their West African congeners. Generalist species among Cichlidogyrus with a sclerotized vagina parasitizing ancient Lake Tanganyika lineages seem to have developed a different hook configuration, most probably to ensure successful colonisation of new, phylogenetically unrelated hosts.     

On the Cyprideis species flock (Crustacea, Ostracoda) in Lake Tanganyika, with the description of four new species

Four new species, belonging to three genera, of ostracods from Lake Tanganyika are described: Mesocyprideis nitida sp.nov., Romecytheridea belone sp.nov., R. plegma sp. nov. and Cyprideis loricata sp. nov. The Cyprideis species flock of Lake Tanganyika now consists of 17 formally described species (16 endemic) in 6 genera (4 endemic). The geographical and ecological distribution of the four species is briefly discussed and some supplementary remarks on the radiation of the Cyprideis species flock in Lake Tanganyika are offered.     

A link between host dispersal and parasite diversity in two sympatric cichlids of Lake Tanganyika

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Three new species of Solicorynespora from Hainan, China

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Systematic revision of the formerly monotypic genus Tanganikallabes (Siluriformes: Clariidae)

The monotypic genus Tanganikallabes, endemic to Lake Tanganyika, is a poorly known member of the family Clariidae. Examination of 142 specimens housed in museum collections has revealed the presence of at least two additional species in this genus. Tanganikallabes alboperca sp. nov. is distinguished from all congeners by the length of its pelvic fins, the presence of a depigmented vertical bar on the opercular margin, and a combination of additional morphometric (pectoral spine length, preanal length, body depth at anus) and meristic (dorsal and anal fin ray counts) characters. Tanganikallabes stewarti sp. nov. is distinguished from other Tanganikallabes species by having a relatively shorter, incomplete lateral line, and shallow body depth at the anus, as well as shorter prepelvic and preanal lengths, and a longer anal fin with a higher number of fin rays. Several morphological characters, as well as genetic data from cytochrome b (mitochondrial DNA) and 18S–ITS1–5.8S–ITS2–28S (ribosomal DNA), indicate that Tanganikallabes constitutes a monophyletic group within the Clariidae and support the recognition of additional species diversity. The monophyly of Tanganikallabes, coupled with the geographical isolation of this group to a single lake satisfy the requirements for its classification as a true species flock, the latest to be described from Lake Tanganyika. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 165 , 121–142.     

New records of Megaselia (Diptera: Phoridae) reared from fungus sporophores in Japan,including five new species

Megaselia donaldsonae Disney sp. nov., M. flava (Fallén), M. gotoi Disney, M. kanekoi Disney, M. margaretae Disney sp. nov., M. nakayamai Disney sp. nov., M. salteri Disney sp. nov. and M. stepheni Disney sp. nov. were reared from sporophores of fungi.     

Systematic study of the genus Compsilura Bouché in Southeast and East Asia with morphological and molecular data (Diptera,Tachinidae)

Compsilura concinnata (Meigen) is one of the most famous, most polyphagous and most widely distributed tachinid flies (Diptera, Tachinidae) in the world. This species is well known as a biocontrol agent of some injurious pests of cultural and wild plants and has been introduced from Europe to the United States to control mainly the gypsy moth. Recently we found three new species very closely resembling C. concinnata from Southeast and East Asia: C. lobata sp. nov. (Japan and Thailand), C. malayana sp. nov. (Malaysia) and C. pauciseta sp. nov. (Japan and Taiwan). Additionally, C. samoaensis Malloch is treated as a junior synonym of C. concinnata based on the examination of the type specimen. The genetic differences in the mitochondrial COI gene data are examined to assess the accuracy of species delimitation of Compsilura. The male postabdominal characters of these species are illustrated. The piercing female postabdomen of C. concinnata is illustrated and compared to those of other members belonging to the Blondelia group including Blondelia Robineau-Desvoidy, Celatoria Coquillett, Eucelatoria Townsend and Vibrissina Rondani.     

Four new species of Gomphocythere (Crustacea, Ostracoda) from Lake Tanganyika, East Africa

Four new species of the ostracod genus Gomphocythere are described from Lake Tanganyika (East Africa): Gomphocythere downingi n. sp. G. coheni n. sp., G. wilsoni n. sp., and G. woutersi n. sp. All species are endemic to the lake and are found within a variety of substrates and depths. The addition of these four new species brings the total number of endemic Gomphocythere species in Lake Tanganyika to nine. Other Gomphocythere species are known from water bodies throughout East and South Africa and in the Levant. Brooding is an important, but not a unique, preadaptation for the persistence and taxic prolific speciation of this lineage in Lake Tanganyika.     

Weak link between dispersal and parasite community differentiation or immunogenetic divergence in two sympatric cichlid fishes

Geographical isolation, habitat variation and trophic specialization have contributed to a large extent to the astonishing diversity of cichlid fishes in the Great East African lakes. Because parasite communities often vary across space and environments, parasites can accompany and potentially enhance cichlid species diversification. However, host dispersal may reduce opportunities for parasite‐driven evolution by homogenizing parasite communities and allele frequencies of immunity genes. To test for the relationships between parasite community variation, host dispersal and parasite‐induced host evolution, we studied two sympatric cichlid species with contrasting dispersal capacities along the shores of southern Lake Tanganyika. Whereas the philopatric Tropheus moorii evolved into several genetically differentiated colour morphs, Simochromis diagramma is phenotypically rather uniform across its distribution range and shows only weak population structure. Populations of both species were infected with divergent parasite communities and harbour differentiated variant pools of an important set of immune genes, the major histocompatibility complex (MHC). The overall extent of geographical variation of parasites and MHC genes was similar between host species. This indicates that immunogenetic divergence among populations of Lake Tanganyika cichlids can occur even in species that are strongly dispersing. However, because this also includes species that are phenotypically uniform, parasite‐induced evolution may not represent a key factor underlying species diversification in this system.     

Diversity and Systematics of Schizomavella Species (Bryozoa: Bitectiporidae) from the Bathyal NE Atlantic

Eight NE Atlantic and Mediterranean species, which were originally assigned to the genus Schizoporella (Family Schizoporellidae) when introduced, are redescribed and stabilized by typification. Seven of these species are transferred to the bitectiporid genus Schizomavella: S. fischeri, S. glebula, S. neptuni, S. obsoleta, S. richardi, S. triaviculata, and S. triaviculata var. paucimandibulata, which is here raised to species rank. The eighth species, Schizoporella fayalensis, is transferred to the lanceoporid genus Stephanotheca. Schizomavella obsoleta and S. glebula are considered junior subjective synonyms of S. fischeri and S. richardi, respectively. Two new species are described: Schizomavella rectangularis n. sp. from the Strait of Gibraltar, and Schizomavella phterocopa n. sp. from the Great Meteor Bank. A new subgenus, Calvetomavella n. subgen. is established as a result of a phylogenetic analysis based on morphological characters; it includes S. neptuni, S. triaviculata, S. paucimandibulata and S. phterocopa n. sp., together with Schizomavella discoidea and Schizomavella noronhai. The rest of the species remain in the nominotypical subgenus Schizomavella.     

High prevalence of non-synonymous substitutions in mtDNA of cichlid fishes from Lake Victoria

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Species-Specific Population Structure in Rock-Specialized Sympatric Cichlid Species in Lake Tanganyika,East Africa

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Two new records of Telenominae (Hymenoptera, Scelionidae) from the Rovno amber (Eocene of Ukraine)

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A NEW BLACKFLY SPECIES OF SIMULIUM (DIPTERA: SIMULIIDAE) FROM GUIZHOU PROVINCE,CHINA*

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Species delimitation in the Andean grasshopper genus Orotettix Ronderos & Carbonell (Orthoptera: Melanoplinae): an integrative approach combining morphological,molecular and biogeographical data

The reciprocal illumination nature of integrative taxonomy through hypothesis testing, corroboration and revision is a powerful tool for species delimitation as more than one source has to support the hypothesis of a new species. In this study, we applied an integrative taxonomy approach combining molecular and morphological data sets with distributional patterns to examine the level of differentiation between and within the grasshopper Orotettix species. Orotettix was described based on five valid species distributed in the Andes of Peru. In our study, initially a molecular‐based hypothesis was postulated and tested against morphological data and geographical patterns of distribution. Results from molecular and morphological analyses showed agreement among the species delimitation in Orotettix, and were also consistent with the geographical distribution. The analyses allowed us to delimit five new species for the genus ( O. lunatus sp. nov. , O . astreptos sp. nov. , O. colcaensis sp. nov. , O . paucartambensis sp. nov. and O . dichrous sp. nov. ) from the Eastern and Western Cordilleras of Peru. We also provide critical knowledge on the phylogenetic relationships and distribution of the genus and conduct a revision of Orotettix. © 2015 The Linnean Society of London