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1.
Zoolog Sci ; 36(6): 511-520, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31833322

RESUMO

To gain a better understanding of the effect of reproductive modes and swimming ability on ostracod distribution, we visited 111 randomly selected aquatic sites in Kirsehir province. A total of 35 ostracods were newly reported for the area. The number of species with and without swimming setae was not statistically different, but numbers of sexual species was significantly lower than parthenogenetics. Species without setae did not show a significant difference between sexual and parthenogenetic forms. Numbers of species with (out) setae were not significant among different elevational ranges. Distribution of parthenogenetic species was common in all 11 habitat types when sexual species were only found from three different types located from 690 to ca. 1400 m of elevational ranges. Numbers of parthenogenetic species with or without setae did not show a difference among the ranges, but sexual species without setae exhibited wider distributional ranges (690-1289 m) than species with swimming setae (690-1089 m). Species' co-occurrence revealed two positive, five negative, and 44 random pairs of co-occurrences. Wards cluster analyses portrayed three main clustering groups. While group I includes parthenogenetic and sexual species, group II covers mostly parthenogenetic species with and without setae. Group III consists of species without setae. CCA results displayed three environmental variables (water temperature, pH and elevation) effective on species distribution. Species distributed in all elevational ranges tend to show lower optimum and wider ecological tolerances. Parthenogenetic species with swimming setae and with relatively higher tolerance ranges were dominant over sexual species. The present results suggest that swimming mode has a greater effect on species distribution among the habitats than reproductive modes.


Assuntos
Crustáceos/fisiologia , Ecossistema , Natação/fisiologia , Distribuição Animal , Animais , Reprodução/fisiologia , Especificidade da Espécie , Turquia
2.
High Alt Med Biol ; 13(2): 126-37, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22724616

RESUMO

We evaluated Rapoport's rule which states a negative correlation between species richness and altitude. To understand the relationship between altitude and reproductive modes (a/sexual) of non-marine ostracods, 166 aquatic bodies in Ordu region, Turkey were randomly sampled from July 11 to July 16, 2010. A total of 26 species of ostracods were found from 133 out of 166 sites. Except for one species (Heterocypris incongruens), the other 25 species were new reports for the region. Candona improvisa was also a new report for Turkish ostracod fauna. Three species (Psychrodromus olivaceus, H. incongruens, and C. neglecta) occurred most frequently as 43, 46, and 76 times, respectively. Canonical correspondence analyses exhibited two variables [Habitat type (p=0.014; F=2.171) and water temperature (p=0.018; F=2.248)] as having the most effect on species. Correlation of species' reproductive modes to those of environmental variables measured was not significant. UPGMA dendrogram displayed 15 most frequently occurring species into four clusters where most species (11) were asexual. Although a small group (asexual species without swimming setae) showed a tendency to habitat type and electrical conductivity, such variables are believed to play secondary role on species distribution. Highest species diversity (13 species) was observed at the range of 1200 and 1400 m (a.s.l.), where numbers of stations sampled was not the highest (22). Numbers of asexual species (19) were higher than the sexual (11) but there were no significant differences (p>0.05) between the frequencies of their occurrences at different altitudinal ranges. Accordingly, our findings do not support the Rapoport Rule. Results yield that reproductive modes of species (sexual and asexual) was not directly correlated to altitude or any environmental variables measured during this study. A better explanation of ostracod diversity appears to be suitability of habitats.


Assuntos
Altitude , Biodiversidade , Crustáceos/fisiologia , Reprodução , Animais , Geografia , Reprodução Assexuada , Especificidade da Espécie , Turquia
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