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Background: African annual killifishes (Nothobranchius spp.) are adapted to seasonally desiccating habitats (ephemeral pools), surviving dry periods as dormant eggs. Given their peculiar life history, geographic aspects of their diversity uniquely combine patterns typical for freshwater taxa (river basin structure and elevation gradient) and terrestrial animals (rivers acting as major dispersal barriers). However, our current knowledge on fine-scale interspecific and intra-specific genetic diversity of African annual fish is limited to a single, particularly dry region of their distribution (subtropical Mozambique). Using a widespread annual killifish from coastal Tanzania and Kenya, we tested whether the same pattern of genetic divergence pertains to a wet equatorial region in the centre of Nothobranchius distribution. Results: In populations of Nothobranchius melanospilus species group across its range, we genotyped a part of mitochondrial cytochrome oxidase subunit 1 (COI) gene (83 individuals from 22 populations) and 10 nuclear microsatellite markers (251 individuals from 16 populations). We found five lineages with a clear phylogeographic structure but frequent secondary contact. Mitochondrial lineages were largely congruent with main population genetic clusters identified on microsatellite markers. In the upper Wami basin, populations are isolated as a putative Nothobranchius prognathus, but include also a population from a periphery of the middle Ruvu basin. Other four lineages (including putative Nothobranchius kwalensis) coexisted in secondary contact zones, but possessed clear spatial pattern. Main river channels did not form apparent barriers to dispersal. The most widespread lineage had strong signal of recent population expansion. Conclusions: We conclude that dispersal of a Nothobranchius species from a wet part of the genus distribution (tropical lowland) is not constrained by main river channels and closely related lineages frequently coexist in secondary contact zones. We also demonstrate contemporary connection between the Ruvu and Rufiji river basins. Our data do not provide genetic support for existence of recently described cryptic species from N. melanospilus complex, but cannot resolve this issue.

Abstract. Body measurements of 110 beef cows of 9 breeds (Hungarian Simmental, Hereford, Aberdeen Angus, Red Angus, Lincoln Red, Shaver, Charolais, Limousin and Blonde d’Aquitaine) were taken in December 2004. The absolute, relative measurements and measurement indices moreover correlations between age, live weight and measurements were evaluated and compared for the mentioned breeds. Animals in study were born between 1989 and 2002, kept on the same condition on peat-bog soil pasture at Keszthely. Significant differences (P<0.05) were found among breeds in most of the body measurements. Blonde d’ Aquitaine was the heaviest in live weight (638 kg), highest as for the height at withers (142.5 cm), height at rump (146.6 cm) and length of the body (151.5 cm). Limousin had longest measurements as for the length of the rump (47.4 cm) and width of the rump (58.3 cm). Shaver had the longest width between shoulders (52.9 cm) and width of the head (25.1 cm) while Lincoln Red the longest length of the head (52.8 cm). The correlations between live weight and measurements were medium or strong positive (r = 0.40–0.83), between age and measurements slight positive (r = 0.01–0.46), among the different measurements medium or strong positive (r = 0.22–0.81).

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Karyotypes of two species of the African annual killifish genus Nothobranchius Peters, 1868, Nothobranchius brieni Poll, 1938 and Nothobranchius sp. from Kasenga (D.R. Congo) are described. Both species displayed diploid chromosome number 2n = 49/50 for males and females respectively with multiple-sex chromosome system type X1X2Y/X1X1X2X2. The karyotypes of studied species are considerably different from those previously reported for the genus Nothobranchius and similar to the Actinopterygii conservative karyotype.