Dataset Information

Discovering Hidden Diversity of Characins (Teleostei: Characiformes) in Ecuador's Yasuni National Park.

ABSTRACT:

Background

Management and conservation of biodiversity requires adequate species inventories. The Yasuní National Park is one of the most diverse regions on Earth and recent studies of terrestrial vertebrates, based on genetic evidence, have shown high levels of cryptic and undescribed diversity. Few genetic studies have been carried out in freshwater fishes from western Amazonia. Thus, in contrast with terrestrial vertebrates, their content of cryptic diversity remains unknown. In this study, we carried out genetic and morphological analyses on characin fishes at Yasuní National Park, in eastern Ecuador. Our goal was to identify cryptic diversity among one of the most speciose fish families in the Amazon region. This is the first time that genetic evidence has been used to assess the species content of the Napo Basin, one of the richest regions in vertebrate diversity.

Results

Phylogenetic analyses of partial mitochondrial 16S ribosomal RNA gene (?600 pb) DNA sequences from 232 specimens of the family Characidae and its closest groups revealed eight candidate new species among 33 species sampled, representing a 24% increase in species number. Analyses of external morphology allowed us to confirm the species status of six of the candidate species.

Conclusions

Our results show high levels of cryptic diversity in Amazonian characins. If this group is representative of other Amazonian fish, our results would imply that the species richness of the Amazonian ichthyofauna is highly underestimated. Molecular methods are a necessary tool to obtain more realistic inventories of Neotropical freshwater fishes.

SUBMITTER: Escobar-Camacho D

PROVIDER: S-EPMC4537159 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Discovering Hidden Diversity of Characins (Teleostei: Characiformes) in Ecuador's Yasuní National Park.

Escobar-Camacho Daniel D Barriga Ramiro R Ron Santiago R SR

PloS one 20150814 8

<h4>Background</h4>Management and conservation of biodiversity requires adequate species inventories. The Yasuní National Park is one of the most diverse regions on Earth and recent studies of terrestrial vertebrates, based on genetic evidence, have shown high levels of cryptic and undescribed diversity. Few genetic studies have been carried out in freshwater fishes from western Amazonia. Thus, in contrast with terrestrial vertebrates, their content of cryptic diversity remains unknown. In this ...[more]

PMID: 26275041

Similar Datasets

Project description:BACKGROUND: The threats facing Ecuador's Yasuní National Park are emblematic of those confronting the greater western Amazon, one of the world's last high-biodiversity wilderness areas. Notably, the country's second largest untapped oil reserves--called "ITT"--lie beneath an intact, remote section of the park. The conservation significance of Yasuní may weigh heavily in upcoming state-level and international decisions, including whether to develop the oil or invest in alternatives. METHODOLOGY/PRINCIPAL FINDINGS: We conducted the first comprehensive synthesis of biodiversity data for Yasuní. Mapping amphibian, bird, mammal, and plant distributions, we found eastern Ecuador and northern Peru to be the only regions in South America where species richness centers for all four taxonomic groups overlap. This quadruple richness center has only one viable strict protected area (IUCN levels I-IV): Yasuní. The park covers just 14% of the quadruple richness center's area, whereas active or proposed oil concessions cover 79%. Using field inventory data, we compared Yasuní's local (alpha) and landscape (gamma) diversity to other sites, in the western Amazon and globally. These analyses further suggest that Yasuní is among the most biodiverse places on Earth, with apparent world richness records for amphibians, reptiles, bats, and trees. Yasuní also protects a considerable number of threatened species and regional endemics. CONCLUSIONS/SIGNIFICANCE: Yasuní has outstanding global conservation significance due to its extraordinary biodiversity and potential to sustain this biodiversity in the long term because of its 1) large size and wilderness character, 2) intact large-vertebrate assemblage, 3) IUCN level-II protection status in a region lacking other strict protected areas, and 4) likelihood of maintaining wet, rainforest conditions while anticipated climate change-induced drought intensifies in the eastern Amazon. However, further oil development in Yasuní jeopardizes its conservation values. These findings form the scientific basis for policy recommendations, including stopping any new oil activities and road construction in Yasuní and creating areas off-limits to large-scale development in adjacent northern Peru.

Project description:Snakehead fishes of the family Channidae are predatory freshwater teleosts from Africa and Asia comprising 38 valid species. Snakeheads are important food fishes (aquaculture, live food trade) and have been introduced widely with several species becoming highly invasive. A channid barcode library was recently assembled by Serrao and co-workers to better detect and identify potential and established invasive snakehead species outside their native range. Comparing our own recent phylogenetic results of this taxonomically confusing group with those previously reported revealed several inconsistencies that prompted us to expand and improve on previous studies. By generating 343 novel snakehead coxI sequences and combining them with an additional 434 coxI sequences from GenBank we highlight several problems with previous efforts towards the assembly of a snakehead reference barcode library. We found that 16.3% of the channid coxI sequences deposited in GenBank are based on misidentifications. With the inclusion of our own data we were, however, able to solve these cases of perpetuated taxonomic confusion. Different species delimitation approaches we employed (BIN, GMYC, and PTP) were congruent in suggesting a potentially much higher species diversity within snakeheads than currently recognized. In total, 90 BINs were recovered and within a total of 15 currently recognized species multiple BINs were identified. This higher species diversity is mostly due to either the incorporation of undescribed, narrow range, endemics from the Eastern Himalaya biodiversity hotspot or the incorporation of several widespread species characterized by deep genetic splits between geographically well-defined lineages. In the latter case, over-lumping in the past has deflated the actual species numbers. Further integrative approaches are clearly needed for providing a better taxonomic understanding of snakehead diversity, new species descriptions and taxonomic revisions of the group.