J. Snoeks results 27
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For many decades, Nannocharax luapulae has been considered to be widespread in the southern part of the Upper Congo basin. However, meristic, morphometric and cytochrome c oxidase subunit I (COI) barcoding evidence revealed that its geographical distribution is restricted to the Luapula‐Moero basin. The populations of the Upper Lualaba are assigned to a new species, N. chochamandai . This new species, though highly similar to...
The value of case reports in rare oncological scenarios: mixed method analysis of colorectal metastases from breast cancerNARA Subscribed
With improved survival of cancer patients, we increasingly encounter infrequent metastatic locations. While for the common metastatic locations both prognostic information as well as evidence-based guidelines are available, for rare locations we have to rely on anecdotal case reports, the value of which is currently unknown. Therefore, we performed a systemic literature review and compare the results with a large national real...
Seeds are essential for plant reproduction, survival, and dispersal. Germination ability and successful establishment of young seedlings strongly depend on seed quality and on environmental factors such as nutrient availability. In tomato ( Solanum lycopersicum ) and many other species, seed quality and seedling establishment characteristics are determined by genetic variation, as well as the maternal environment in which the...
Objective The purpose of the present study was to investigate the association between cardiorespiratory fitness (CRF) measured as peak oxygen uptake (VO 2peak , expressed in mL/min) and body mass index (BMI) in a large cohort of apparently healthy subjects. Methods BMI and VO 2peak were measured in a cross-sectional study of 8470 apparently healthy adults. VO 2peak (mL/min) was determined by an incremental cycle ergometer test...
Species richness in the African pike genus Hepsetus : a perfect match between genetics and morphologyNARA Subscribed
In this study, morphological differences were found that corroborate earlier results that showed the existence of six species within the previously monospecific African pike genus Hepsetus . Additional genetic data ( coI , mtDNA and rag1 , nDNA) confirm the morphology‐based species delineations. Deep genetic divergences imply a relatively old age for diversification within the genus. An identification key for the six species i...
Re‐establishment of the genus Monostichodus Vaillant 1886 ( C haraciformes, D istichodontidae)NARA Subscribed
Pellegrin rejected the validity of Monostichodus elongatus , described by Vaillant and type species of the genus Monostichodus , based on the lack of a proper species description, and redescribed Vaillant's specimens as Hemistichodus vaillanti . After review of the relevant articles in the International Code of Zoological Nomenclature, however, no arguments were found to consider M. elongatus as a nomen nudum . This implies th...
Natural epigenetic variation contributes to heritable flowering divergence in a widespread asexual dandelion lineageNARA Subscribed
Epigenetic variation has been proposed to contribute to the success of asexual plants, either as a contributor to phenotypic plasticity or by enabling transient adaptation via selection on transgenerationally stable, but reversible, epialleles. While recent studies in experimental plant populations have shown the potential for epigenetic mechanisms to contribute to adaptive phenotypes, it remains unknown whether heritable vari...
Epigenetic modifications, such as DNA methylation variation, can generate heritable phenotypic variation independent of the underlying genetic code. However, epigenetic variation in natural plant populations is poorly documented and little understood. Here, we test whether northward range expansion of obligate apomicts of the common dandelion ( Taraxacum officinale ) is associated with DNA methylation variation. We characteriz...
Labeo rosae (Cypriniformes: Cyprinidae) in the Congo basin: a relict distribution or a historical introduction?NARA Subscribed
Labeo rosae , a species with a native range in Southern Africa, was discovered in the Congo basin by re‐identification of two museum specimens previously identified as Labeo mesops . The occurrence of this species in the upper Congo implies a range extension of the species of more than 1000 km. Although the species' distribution is mirrored by that of some other Cypriniformes, its occurrence in the Congo might be due to introd...
A revision of the Lower Guinean Hepsetus species (Characiformes; Hepsetidae) with the description of Hepsetus kingsleyae sp. novNARA Subscribed
An α‐taxonomic revision of the African pike, Hepsetus odoe , from Lower Guinea is provided. The results show that three different species occur in Lower Guinea instead of one. Hepsetus akawo , recently described from West Africa, is present in the northern part of Lower Guinea; Hepsetus lineata , the most widespread species within Lower Guinea, is known from the Sanaga (Cameroon) in the north to the Shiloango ( Democratic Repu...
We used nuclear and mitochondrial DNA (mtDNA) sequences from specimens collected throughout Lake Tanganyika to clarify the evolutionary relationship between Lamprologus callipterus and Neolamprologus fasciatus . The nuclear data support the reciprocal monophyly of these two shell‐breeding lamprologine cichlids. However, mtDNA sequences show that (i) L. callipterus includes two divergent and geographically disjunct (North–South...
A new mastacembelid species from Lake Tanganyika: a case of complex evolutionary historyNARA Subscribed
A detailed morphometric study of 123 specimens identified as Mastacembelus albomaculatus and the six syntypes of M. tanganicae was undertaken. On each specimen, 27 morphometric measurements and 12 meristics were taken. The type series of M. tanganicae contains more than one species, with four specimens attributed to a new species M. reygeli sp. nov. A redescription of M. albomaculatus and a description of the new species are p...
The colour pattern of the caudal fin, a useful criterion for identification of two species of Tilapia and their hybridsNARA Subscribed
The present work reports on some chromatic characters and their change with size in two species of Tilapia ( T. zillii and T. guineensis ) and their first generation hybrids. Successful reciprocal hybridizations between T. zillii and T. guineensis were performed in concrete tanks. The hybrids obtained were viable. The colour patterns of the hybrids and their parents were registered during a rearing cycle of 12 months. Between...
A detailed morphological comparison of Trematochromis schreyeni only known from its holotype, collected at the north‐western end of Lake Tanganyika, and ‘ Ctenochromis ’ benthicola described from the same region, and some additional material led to the conclusion that the two species were conspecifics. Consequently, T. schreyeni is considered to be a junior synonym of ‘ C .’ benthicola , an endemic species to the lake. A redes...
A new species and geographical variation in the Telmatochromis temporalis complex (Teleostei, Cichlidae) from Lake TanganyikaNARA Subscribed
Telmatochromis brachygnathus sp.n. is described from the southern and central parts of Lake Tanganyika. It can be distinguished from the similar T. temporalis mainly by its smaller mouth. Morphological distinct populations were found in both species.
Zinc and cobalt are essential trace metals for phytoplankton growth and can substitute for each other metabolically in some eukaryotic algal species, especially in some marine diatoms and coccolithophorids. In the present study, it is reported that in the marine diatom Chaetoceros calcitrans , Co cannot replace Zn: in contrast, Co substitution of Zn was found in Emiliania huxleyi . It is concluded that Co can substitute for Zn...
A revised synonymy of Telmatochromis temporalis (Teleostei, Cichlidae) from Lake Tanganyika (East Africa)NARA Subscribed
The taxonomic status of the nominal species Telmatochromis temporalis , T. lestradei , T. burgeoni and Julidochromis macrolepis has been reviewed. The synonymy of T. lestradei with T. temporalis is confirmed. A comparison of Telmatochromis burgeoni with Telmatochromis temporalis revealed no significant differences either. Hence T. burgeoni is considered synonymous with T. temporalis . Examination of the type of Julidochromis m...