Genetic variation at mtDNA and microsatellite loci in Chinese longsnout catfish (Leiocassis longirostris)

Abstract

Genetic variability and population structure of the Chinese longsnout catfish Leiocassis longirostris Günther in the Yangtze River was examined with mitochondrial control region sequences and nuclear microsatellite markers. A 705-bp segment of the mitochondrial DNA control region was sequenced from 132 samples, which identified a total of 61 haplotypes. The Chinese longsnout catfish in the Yangtze River was characterized with high haplotype diversity (h = 0.9770 ± 0.0041) but low nucleotide diversity (π = 0.0081 ± 0.0043). Median-joining network analysis revealed a star-shaped pattern and mismatch distribution analysis found a smooth unimodal distribution, which suggested that this species in the Yangtze River underwent a population expansion following bottlenecks and/or they originated from a small size of founding population. It was estimated that the possible time of population expansion was 139,000-435,000 years before present, a time period in the middle Pleistocene. The analysis of molecular variance and phylogenetic reconstructions did not detect significant geographic structure between different river sections. This pattern of genetic variation was further evidenced with nuclear microsatellite markers. The genetic differentiation between above and below the Gezhouba Dam and Three Gorges Dam is very small at mitochondrial and nuclear levels, which suggested that these recently developed dams might have not significantly resulted in population genetic fragmentation in the Chinese longsnout catfish. However, the potential exacerbation of genetic structuring by the dams should not be overlooked in the future.

Identification and characterization of microsatellite markers for the population genetic structure in endemic red-tailed barb, Gonoproktopterus curmuca

“…This can be due to the extremely fast rates of repeat evolution that may differ among loci, but keeping the highly conservative flanking regions unchanged, as reported by Zardoya et al (1996) in cichlids and other Perciform fishes. The present study found GT and CA rich microsatellites abundant in G. curmuca which is in conformity with the published reports [45][46][47][48][49].…”

Populations genetically rifting within a complex geological system: The case of strong structure and low genetic diversity in the migratory freshwater catfish,Bagrus docmak,in East Africa

“…Additional evidence of low diversity in the mitochondrial data reveals that the populations from Lakes Victoria and Edward have been restricted to a very small size over a few thousands of years. High haplotype diversity coupled with low nucleotide diversity as was observed in the Lake Victoria and Edward B. docmak populations (Table ), is a pattern consistent with one which has been documented in another catfish species, L. longirostris (Yang et al., ). This pattern has been associated with recent population expansions following population bottlenecks (Grant & Bowen, ; Yang et al., ).…”

“…High haplotype diversity coupled with low nucleotide diversity as was observed in the Lake Victoria and Edward B. docmak populations (Table ), is a pattern consistent with one which has been documented in another catfish species, L. longirostris (Yang et al., ). This pattern has been associated with recent population expansions following population bottlenecks (Grant & Bowen, ; Yang et al., ). Evidence of a historical bottleneck and a possible recent colonization was also confirmed by the negative and significant Fu's statistic obtained in the Lake Victoria, Lake Edward, and Kazinga channel populations (Fu, ).…”

Population genetics and sympatric divergence of the freshwater gudgeon, Gobiobotia filifer, in the Yangtze River inferred from mitochondrial DNA

“…MtDNA Cyt b gene sequences have been used to study population genetics of some fishes in the Yangtze River, for example, Zacco platypus (Perdices, Cunha, & Coelho, ), Leiocassis longirostris (Xiao, Xia, & Ma, ; Yang, Xiao, Yu, & Xu, ), Leptobotia elongata (Tian, Duan, Wang, Liu, & Chen, ), Siniperca chuatsi (Tian et al, ), and Saurogobio dabryi (Li, Tang, Yu, & Liu, ). Compared to these fishes, the genetic diversity of G. filifer is currently high.…”

“…Population expansions (Table ) occurred in the last glacial period (10,000–70,000 years ago), and temperature and rainfall began to increase at that time in east China (Song, Yu, & Zhu, ). Many fishes in the Yangtze River have been reported to experience population bottleneck followed by expansion, such as Leiocassis longirostris (Yang, Xiao, et al, ), Squalidus argentatus (Yang, Tang, et al, ), Gymnocypris dobulai (Chan, Li, Hu, Liu, & Xu, ), and Parabramis pekinensis (Chen et al, ). The asymmetric proportion of HapGroup 1 to HapGroup 2 populations could be interpreted as different founder sizes and panmixia after recontact of distinct populations, but nuclear maker is needed to support this hypothesis.…”