Fernanda Simões de Almeida

Analysis by RAPD of the genetic structure of Astyanax altiparanae (Pisces, Characiformes) in reservoirs on the Paranapanema River, Brazil

In this study, the RAPD technique was used to analyze the genetic structure of populations of the fish Astyanax altiparanae (Characidae, Tetragonopterinae) living in the lower, middle and upper Paranapanema River, Brazil. The aim was to assess this structure regarding fish handling and conservation programs. The genetic variability (P) was found to be 42.64%, 75% and 75% in the low, middle and upper reaches, respectively. The dendrogram of genetic similarity, obtained by comparative analysis of the sets of samples from the three sites, showed the formation of three clusters. All of the genetic parameters used indicate that the population in the lower Paranapanema is genetically different from those in the middle and upper sections. The theta P test shows that the low Paranapanema is highly differentiated from the middle (0.2813) and upper (0.2912) Paranapanema, while the differentiation between the last two is moderate (0.0895). The data obtained in the present work suggest that recolonization and conservation studies should not be focused on the species A. altiparanae as such, but on the conservation units, because they are the genetically differentiated populations.

Fish passage ladders from Canoas Complex - Paranapanema River: evaluation of genetic structure maintenance of Salminus brasiliensis (Teleostei: Characiformes)

The aim of this study, utilizing RAPD techniques, was to determine the genetic variability of Salminus brasiliensis groups collected at passage ladders of the hydroelectric plants (HEP) Canoas I and Canoas II - Paranapanema River (Brazil), as well as to estimate the population structure through different parameters of genetic diversity. The data obtained allowed us to conclude that S. brasiliensis of the Canoas Complex has a moderate index of genetic variability ( > 42.00%) when compared to that of other migratory fish species. All genetic diversity analyses (distance = 0.015 and genetic identity = 0.985, FST =0.018, AMOVA) were signs of low genetic differentiation, and they led to the clustering of S. brasiliensis from Canoas I and Canoas II. This suggests that the species is genetically structured as a single population. Some findings indicate that this population of S. brasiliensis comes from the Capivara Reservoir (Canoas I downstream), probably fed by the Tibagi and Cinzas Rivers. Literature data denote that after fish transposition by passage ladders of the Canoas Complex, the migratory species are not concluding the reproductive cycle. This mechanism, therefore, could be one more impact factor causing the depletion in downstream recruitment, which could in medium and long term be compromising the natural S. brasiliensis population in the middle Paranapanema River.

Population genetic structure of Astyanax scabripinnis (Teleostei, Characidae) from an urban stream

Despite the great anthropogenic interference on urban streams, information is still scarce about the genetic variability and structure of native fish populations inhabiting such streams. In the present study, random amplified polymorphic DNA (RAPD) markers were used to analyze genetic variability and structure of populations assigned to the Neotropical fish species Astyanax scabripinnis from an urban stream located in Londrina, Paraná State, southern Brazil. Thirty individuals of this species were collected from three sites throughout the upper Cambé stream. A total of 10 primers amplified 159 loci, of which 128 (80.5%) were polymorphic. Each of the three populations showed very similar proportions of polymorphic loci, which ranged from 63.5 to 64.8%. Unbiased genetic distances varied from 0.0612 to 0.0646. Thetap-test values indicated moderate to high genetic differentiation among individuals from different localities. The number of migrants varied from 1.34 to 1.46, suggesting a low gene flow between populations. The genetic similarity among all individuals studied ranged from 0.424 to 0.848. The results suggest that populations of A. scabripinnis in Cambé stream are undergoing genetic differentiation.

RAPD and isoenzyme analysis of genetic variability in three allied species of catfish (Siluriformes: Pimelodidae) from the Tibagi River, Brazil

Genetic variability in three species of Pimelodidae catfish (Iheringichthys labrosus, Pimelodus maculatus and Pimelodus cf. absconditus), collected at four sites in the Tibagi river-basin: Sertaneja, Londrina (lower Tibagi), Sapopema (middle Tibagi) and Tibagi (upper Tibagi) was analysed using RAPD and isoenzymatic techniques. Iheringichthys labrosus had the greatest genetic variability showing a proportion of mean polymorphic loci (Pm) of 53.7+. The dendrogram showed that the individuals from the locations were clustered together, supporting the hypothesis that I. labrosus has a sedentary or localized geographical distribution. Pimelodus maculatus is the only species studied that is considered to be highly migratory. The Pm obtained for this species was 30.2+. Their genetic dendrogram showed that the individuals were not clustered, based on the place of collection. P. cf. absconditus had a Pm value of 47.4+, and the external morphology of this species is similar to that of I. labrosus, which hindered differentiation of individuals from the two species. RAPD and isoenzyme analysis, however, provided differential patterns for P. cf. absconditus from I. labrosus.

Genetic structure analysis of Eufriesea violacea (Hymenoptera, Apidae) populations from southern Brazilian Atlantic rainforest remnants

Random amplified polymorphic DNA (RAPD) markers were used to analyze the genetic structure of Eufriesea violacea populations in three fragments (85.47, 832.58 and 2800 ha) of Atlantic rainforest located in the north of the Brazilian state of Parana. A total of twelve primers produced 206 loci, of which 129 were polymorphic (95% criterion). The proportions of polymorphic loci in each population ranged from 57.28% to 59.2%, revealing very similar levels of genetic variability in the groups of bees from each fragment. Unbiased genetic distances between groups ranged from 0.0171 to 0.0284, the smallest genetic distance occurring between bees from the two larger fragments. These results suggest that the E. violacea populations from the three fragments have maintained themselves genetically similar to native populations of this species originally present in northern Parana.

DNA barcoding of freshwater ichthyoplankton in the Neotropics as a tool for ecological monitoring

Quantifying and classifying ichthyoplankton is one of the most effective ways of monitoring the recruitment process in fishes. However, correctly identifying the fish based on morphological characters is extremely difficult, especially in the early stages of development. We examined ichthyoplankton from tributaries and reservoirs along the middle stretch of the Paranapanema River, one of the areas most impacted by hydroelectric projects in the Neotropics. Matching DNA sequences of the COI gene (628–648 bp) allowed us to identify 99.25% of 536 samples of eggs (293) and larvae (243) subjected to BOLD‐IDS similarity analysis with a species‐level threshold of 1.3%. The results revealed 37 species in 27 genera, 15 families and four orders, some 23.8% of documented fish species in the Paranapanema River. Molecular identification meant that we could include data from egg samples that accounted for about 30% of the species richness observed. The results in this study confirm the efficacy of DNA barcoding in identifying Neotropical ichthyoplankton and show how the data produced provide valuable information for preparing plans for conserving and managing inland waters.

Analysis of genetic variability in three species of Pimelodidae (Ostariophysi - Siluriformes)

Genetic variability of three Pimelodidae species, Pimelodus maculatus, Iheringichthys labrosus, and Pinirampus pirinampu, collected at one site in the Tibagi River, was comparatively analyzed using protein data for six systems which code 15 loci in liver, muscle, and heart. The proportion of polymorphic loci () for P. maculatus, I. labrosus, and P. pirinampu was 13.33, 20, and 6.67%, respectively, and mean heterozigosity was 6, 8.3, and 4.3%. The genetic identity value (I) was 0.32 between P. maculatus and I. labrosus, 0.37 between P. maculatus and P. pirinampu, and 0.58 between I. labrosus and P. pirinampu. This value suggests that these two latter species are congeneric. However, morphological characteristics place these species in distinct genera.

Development and characterization of 14 microsatellite loci in the Neotropical fish Geophagus brasiliensis (Perciformes, Cichlidae).

Fourteen polymorphic microsatellite loci were isolated and characterized for the Neotropical cichlid Geophagus brasiliensis and tested on 30 individuals belonging to a single population. Among the 14 loci described, four showed potential presence of null alleles, inferred from the excess of homozygous genotypes, and three of these loci showed significant deviations from Hardy-Weinberg equilibrium. Fifty-nine different alleles were detected (ranging from two to eight alleles per locus), with estimates of observed and expected heterozygosity ranging from 0·167 to 0·700 and from 0·269 to 0·825. Cross-amplification of primers was successful in five other cichlid species.

Genetic diversity of the species Leporinus elongatus (Teleostei: Characiformes) in the Canoas Complex - Paranapanema River

Dams constructed along waterways interrupt the dispersion and migration of aquatic organisms, affecting mainly the abundance of migratory fish species. Translocation mechanisms have been constructed at dams aiming to minimize their impact on fish species migration behavior. There is little information available about the effect of the construction of dams on the genetic structure of the Neotropical migratory fish fauna. Therefore, RAPD molecular markers and microsatellites were utilized to evaluate the diversity and genetic structure of the migratory species Leporinus elongatus (piapara) in the Canoas Complex - Paranapanema River - Brazil. Ten groups were sampled in the fish ladders of the hydroelectric dam Canoas I and Canoas II during the reproductive period in three consecutive years. Both markers showed a high level of genetic diversity within these groups. The microsatellite markers demonstrated a loss of heterozygosity and a considerable level of inbreeding in the species. The genetic differentiation found among the groups with both markers utilized is within a range from low to moderate. The data obtained with the parameter of genetic diversity among the groups led to the conclusion that the groups of L. elongatus of the Canoas Complex are structured as a single population composed of sub-populations with low genetic diversity among them. The data on genetic diversity and population structure of L. elongatus are of great importance for the development of the species management and conservation programs in the Canoas Complex, which can also be utilized in aquaculture programs.

Reproductive Aspects of Moenkhausia intermedia Eigenmann, 1908 (Pisces, Characidae) in the Upper Paraná River Basin, Brazil

The aim of this work was to determine the reproductive tactic of the population of Moenkhausia intermedia, inhabiting the Capivara Reservoir, lower Paranapanema River. Four different stretches of the reservoir were selected, and sampling was carried out quarterly, in the period from 2001 to 2004. Fish were captured utilizing gill nets, cast nets, and seine nets. Later, fish were identified and measured and had their sex identified. Here we describe sex proportion, standard length at first maturation (𝐿50), site and period of spawning, fecundity and type of spawning. The population showed an effective reproductive activity in the area, with the number of females higher than males and 𝐿50 corresponding to 6,1 cm and 5,5 cm, respectively. A greater intensity of spawning occurred in the warmest months. Reproductive activity was identified in all stretches studied, and the absolute fecundity average was 9611 oocytes per gonad, and the mean relative fecundity corresponded to 1065 oocytes/grams.