Geographical genetics of Pseudoplatystoma punctifer (Castelnau, 1855) (Siluriformes, Pimelodidae) in the Amazon Basin.
Geographical genetics allows the evaluation of evolutionary processes underlying genetic variation within and among local populations and forms the basis for establishing more effective strategies for biodiversity conservation at the population level. In this study, we used explicit spatial analyses to investigate molecular genetic variation (estimated using 7 microsatellite markers) of Pseudoplatystoma punctifer, by using samples obtained from 15 localities along the Madeira River and Solimões, Amazon Basin. A high genetic diversity was observed associated with a relatively low FST (0.057; P < 0.001), but pairwise FST values ranged from zero up to 0.21 when some pairs of populations were compared. These FST values have a relatively low correlation with geographic distances (r = 0.343; P = 0.074 by Mantel test), but a Mantel correlogram revealed that close populations (up to 80 km) tended to be more similar than expected by chance (r = 0.360; P = 0.015). The correlogram also showed a exponential-like decrease of genetic similarity with distance, with a patch-size of around 200 km, compatible with isolation-by-distance and analogous processes related to local constraints of dispersal and spatially structured levels of gene flow. The pattern revealed herein has important implications for establishing strategies to maintain genetic diversity in the species, especially considering the threats due to human impacts caused by building large dams in this river system.
Laboratório de Genética & Biodiversidade, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, GO, Brasil tellesmpc@gmail.com.
M P C
MP
Telles
Laboratório de Genética & Biodiversidade, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, GO, Brasil.
R G
RG
Collevatti
Laboratório de Genética & Biodiversidade, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, GO, Brasil.
R S
RS
Braga
Laboratório de Genética & Biodiversidade, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, GO, Brasil.
L B S
LB
Guedes
Laboratório de Genética & Biodiversidade, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, GO, Brasil.
T G
TG
Castro
Systema Naturae Consultoria Ambiental LTDA, Goiânia, GO, Brasil.
M C
MC
Costa
Systema Naturae Consultoria Ambiental LTDA, Goiânia, GO, Brasil.
N J
NJ
Silva-Júnior
Departamento de Zoologia, Museu Paraense Emílio Goeldi, Belém, PA, Brasil.
R B
RB
Barthem
Departamento de Ecologia, Instituto de Ciências Biológicas.
J A F
JA
Diniz-Filho
D000818:Animals; D005075:Biological Evolution; D002397:Catfishes / Q000235:genetics*; D003247:Conservation of Natural Resources; D014644:Genetic Variation; D005828:Genetics, Population; D006801:Humans; D058974:Phylogeography; D045483:Rivers