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•Another matamata species is described as new to science.•Chelus orinocensis is genetically and morphologically significantly different.•Chelus orinocensis and C. fimbriata diverged ...approximately 13 million years ago.•Chelus orinocensis lives in the Orinoco, Río Negro, and Essequibo drainages.•Chelus fimbriata sensu stricto occurs in the Amazon and Mahury drainages.
The matamata is one of the most charismatic turtles on earth, widely distributed in northern South America. Debates have occurred over whether or not there should be two subspecies or species recognized due to its geographic variation in morphology. Even though the matamata is universally known, its natural history, conservation status and biogeography are largely unexplored. In this study we examined the phylogeographic differentiation of the matamata based on three mitochondrial DNA fragments (2168 bp of the control region, cytochrome oxidase subunit I, and the cytochrome b gene), one nuclear genomic DNA fragment (1068 bp of the R35 intron) and 1661 Single Nucleotide Polymorphisms (SNPs). Our molecular and morphological analyses revealed the existence of two distinct, genetically deeply divergent evolutionary lineages of matamatas that separated in the late Miocene (approximately 12.7 million years ago), corresponding well to the time when the Orinoco Basin was established. As a result of our analyses, we describe the genetically and morphologically highly distinct matamata from the Orinoco and Río Negro Basins and the Essequibo drainage as a species new to science (Chelus orinocensis sp. nov.). Chelus fimbriata sensu stricto is distributed in the Amazon Basin and the Mahury drainage. Additionally, the analyses revealed that each species displays phylogeographic differentiation. For C. orinocensis, there is moderate mitochondrial differentiation between the Orinoco and the Río Negro. For C. fimbriata, there is more pronounced differentiation matching different river systems. One mitochondrial clade was identified from the Amazon, Ucayali, and Mahury Rivers, and another one from the Madeira and Jaci Paraná Rivers. The C. orinocensis in the Essequibo and Branco Rivers have haplotypes that constitute a third clade clustering with C. fimbriata. Phylogenetic analyses of the R35 intron and SNP data link the matamatas from the Essequibo and Branco with the new species, suggesting past gene flow and old mitochondrial introgression. Chelus orinocensis is collected for the pet trade in Colombia and Venezuela. However, neither the extent of the harvest nor its impact are known. Hence, it is crucial to gather more information and to assess its exploitation throughout its distribution range to obtain a better understanding of its conservation status and to design appropriate conservation and management procedures.
La matamata es una de las tortugas más carismáticas del mundo, ampliamente distribuida en el norte de Sudamérica. Debido a su variación morfológica geográfica, se debate sobre el reconocimiento de dos subespecies o especies. A pesar de que la matamata es universalmente conocida, su historia natural, estado de conservación y biogeografía han sido muy poco estudiados. En este estudio examinamos la diferenciación filogeográfica de las matamatas en base a tres fragmentos de ADN mitocondrial (2168 pb de la región de control, la subunidad I del citocromo oxidasa y el gen del citocromo b), un fragmento de ADN genómico nuclear (1068 pb del intrón R35) y 1661 polimorfismos de nucleótido único (SNPs). Nuestros análisis moleculares y morfológicos revelaron la existencia de dos linajes evolutivos distintos de matamatas, genéticamente divergentes que se separaron en el Mioceno tardio (hace aproximadamente 12.7 millones de años), correspondiendo al tiempo en que se estableció la cuenca del Orinoco. Como resultado de nuestros análisis, describimos las genéticamente y morfológicamente distintas matamatas de las cuencas del Orinoco, Río Negro y Essequibo como una especie nueva para la ciencia (Chelus orinocensis sp. nov.). Chelus fimbriata sensu stricto se distribuye en la cuenca del Amazonas y en el drenaje del Mahury. Adicionalmente, los análisis revelaron que cada especie muestra diferenciación filogeográfica. Para C. orinocensis, hay una moderada diferenciación mitocondrial entre el Orinoco y el Río Negro. Para C. fimbriata, hay una diferenciación más pronunciada, concordando con los diferentes sistemas fluviales. Se identificó un clado de los ríos Amazonas, Ucayali y Mahury y otro de los ríos Madeira y Jaci Paraná. Las C. orinocensis de los ríos Essequibo y Branco tienen haplotipos que constituyen un tercer clado que se agrupa con C. fimbriata. Los análisis filogenéticos del intrón R35 y los datos de SNP asocian las matamatas de Essequibo y Branco con la nueva especie, sugiriendo flujo de genes pasado e introgresión mitocondrial antigua. Chelus orinocensis se colecta para el comercio de mascotas en Colombia y Venezuela. Sin embargo, ni se conoce el alcance de las colectas ni su impacto. Por lo tanto, es crucial recopilar más información y evaluar su explotación en todo su rango de distribución, comprender mejor su estado de conservación y para diseñar acciones apropiadas de conservación y manejo.
Abstract Dwarf caiman species of the genus Paleosuchus (Paleosuchus palpebrosus and Paleosuchus trigonatus) are old, widespread crocodilian lineages with populations affected by habitat modification. ...For both species, phylogeographical studies revealing crucial information have already been performed, but for important ecoregions, such as the Orinoco, knowledge is lacking. In this study, the phylogenetic identity of individuals of Paleosuchus spp. from the Orinoco basin of Colombia and Venezuela was evaluated. The genetic structure of the two species of Paleosuchus was also determined and their genetic diversity quantified. The results show a marked genetic structuring in both species, also indicating that the populations of P. trigonatus and P. palpebrosus of the Orinoco basin are well differentiated from those of other hydrographic basins. For Colombia, it was possible to infer that there are two independent management units for both species (Orinoco and Amazonas) and that the populations of the Orinoco basin present high genetic and haplotypic diversity. In Venezuela, only one management unit was identified for each species. This finding, together with the results of previous studies, show that, in total, there are at least five management units for P. palpebrosus and six for P. trigonatus, throughout their distribution areas. It is necessary to take this information into account when establishing conservation strategies for these species, although it is stressed that the geographical sampling must be improved in future phylogeographical studies, because information gaps persist at the geographical level.
The turtle genus
Kinosternon
is widespread with at least 25 species distributed from Mexico to northern Argentina. The taxonomy of this genus is controversial and requires a full revision using both ...morphological and molecular approaches. In this study, we did a genomic analysis on the species
Kinosternon scorpioides
distributed in insular and continental Colombia in order to define conservation units. Total DNA was extracted from 24 tissue samples and RADseq genotyping analysis was done. In addition, the intron R35 was amplified and sequenced for a subset of samples. A total of 35,507 SNPs combined with 1,047 bp of the intron were used for spatiotemporal colonization pattern reconstruction and phylogenetic analyses. In addition, SNPs were used for population structure inferences and allele frequency-based analyses. Reciprocal monophyly, significant differences in allele frequencies (
F
st
= 0.32 - 0.78), and evidence of reproductive isolation (no admixture/geneflow), indicate long-term divergence between groups (2-8 MYA), possibly due to geographical barriers. Four Evolutionarily Significant Units (ESUs) were defined within our samples. One ESU was represented by the insular subspecies
K. scorpioides albogulare
, found on San Andrés island, and three ESUs were defined for the subspecies
K. s. scorpioides
in continental Colombia: one
trans
-Andean, found in northwestern Colombia (Caribbean region) and two
cis
-Andean, found in eastern and southeastern Colombia in the Orinoco and Amazon regions, respectively. Colonization of this species occurred from an ancestral area on South of Central America region (~ 8.43 MYA), followed by an establishing of current populations on San Andrés Island and then, in the continent. First, in the Colombian Caribbean, next, in the Orinoco, and more recently, in the Amazon. We hypothesize that the emergence of the Panamá Isthmus, as well as the final uplift of the North Eastern Andes and Vaupes Arch, were key event leading to the differentiation of these ESUs. For management and conservation purposes, each of these ESUs should be considered as a separate management unit. A full revision of the taxonomy of the genus
Kinosternon
is warranted.
The lack of clarity regarding the taxonomy of the ocellate river stingray (Potamotrygon motoro) and the absence of previous studies regarding its genetic diversity and population structure makes this ...species vulnerable to overexploitation, being now the second species of freshwater ray most extracted and exported for ornamental purposes in Colombia. The aim of this work was to determine the population genetic structure and genetic diversity of P. motoro in the Colombian Amazon and Orinoco basins. A total of 110 samples collected from six sub-basins of the Orinoco and in two sub-basins of the Amazon, were analyzed by amplification and sequencing of two fragments of the mitochondrial genes, Cytochrome oxidase subunit I (COI) (532 bp), and Cytochrome b (Cytb) (429 bp). Haplotype networks were constructed, followed by an analysis of molecular variance (AMOVA). The most probable number of genetic groups (K) was evaluated by means of Bayesian inference using BAPS. One shared haplotype was found between the Colombian Amazon and Orinoco basins for COI but no shared haplotypes were found for Cytb. A K of 4 was found, differentiating three of the four units by sub-basins. A high and significant F
ST
was found when comparing the two basins, suggesting significant genetic differentiation between basins for both mitochondrial gene fragments. These results suggest that P. motoro populations in Colombia should be managed as independent units in each basin for conservation and extraction purposes.
The matamatas (Chelus fimbriata and the recently described Chelus orinocensis) are the largest species in the family Chelidae, easily identified by their distinct morphological characteristics. The ...matamatas have a wide distribution in South America, occurring in Bolivia, Brazil, Colombia, Ecuador, Guyana, French Guiana, Peru, and Venezuela, as well as Trinidad and Tobago. However, there are many gaps in the knowledge of its distribution. The objective of this study was to present new records of occurrence for the C. fimbriata species complex and describe the area of distribution. We compiled data from published papers, databases in museums and other scientific collections, and research institutes and conservation organizations. From these data we mapped the species distribution, considering 3 types of river drainages based on water color in the Amazon Basin. We added 182 new records in Brazil, Venezuela, Colombia, Bolivia, and Peru, demonstrating that the C. fimbriata species complex has a wide distribution, totaling 6,907,551 km2 across all 3 river types. Most records were concentrated in areas lower than 200 m above sea level.
This is the first report demonstrating that
Boana tetete
and
B. maculateralis
occur in the Colombian Amazon Basin. These specimens were identified previously as
Boana fasciata
; however, morphology ...and current distribution records show that the specimens were misidentified. These new records extend the known distribution of the
B. tetete
630 km north from nearest locality in the Ecuadorian Amazon and 420 km for
B. maculateralis
. An updated map of current distribution and ecoregional areas in Amazonian is provided.
The freshwater stingray Paratrygon aiereba have coloration, osteological and morphometric variations that could suggest the existence of more than one species in Colombia. In order to evaluate the ...phylogeography, population structure and genetic diversity for P. aiereba distributed in the Amazon and Orinoco basins, we amplified Cytochrome oxidase subunit 1 (COI) partial region of mitochondrial DNA (mtDNA) in 50 samples from eight different sub-basins. Our results suggest three phylogroups and a vicariance event occurred 43 million years ago proposing how Paratrygon diverged into the basins. A high population structure (Φ
ST
= 0.692; p < 0.005) and a value of (K) of 3 were defined. A high genetic diversity within phylogroups was found: Phylogroup A (h = 0.64; π% = 2.48), Phylogroup B (h = 0.552; π% = 1.67), and Phylogroup C (h = 0.49; π% = 0.73). These results should be considered in local management plans, conservation programs and reclassification in at least Amazon and Orinoco.
Resumen Se registra por primera vez para Colombia (cuenca del Orinoco), cuatro especies de crustáceos ectoparásitos en rayas de agua dulce (Potamotrygonidae), género Potamotrygon. Dos que pertenecen ...a la subclase Branchiura, familia Argulidae: Dolops reperta (Bouvier, 1899) y D. striata (Bouvier, 1899) y dos al orden Isopoda, correspondientes a las familias Cymothoidae y Corallanidae, representadas con las especies Braga cigarra (Szidat & Schubart, 1960) y Excorallana delaneyi (Stone & Heard, 1989), respectivamente.
Se presentan los resultados de una iniciativa interinstitucional (Corpoamazonia, Corporinoquia, Instituto Humboldt, Universidad de Los Andes y Fundación Omacha), donde se verificó, con herramientas ...moleculares, que varios lotes de tortugas matamata (Chelus fimbriata) decomisadas en la ciudad de Leticia, departamento del Amazonas, Colombia, correspondían a ejemplares capturados en la Orinoquia y cuyo destino final era aparentemente Perú, como parte de una red de tráfico de fauna. Basados en este hallazgo, 2 corporaciones liberaron 400 individuos neonatos en el en el río Bita y la Reserva Natural Privada Bojonawi en el departamento del Vichada, Orinoquia colombiana. Se evidencia el tráfico de esta especie probablemente hacia Perú, donde la comercialización de tortugas es legal. Se recomienda el uso de protocolos de identificación genética para determinar y controlar la procedencia geográfica de tortugas decomisadas a futuro, como paso previo y necesario para su liberación.
Resumen Se presentan los resultados de una iniciativa interinstitucional (Corpoamazonia, Corporinoquia, Instituto Humboldt, Universidad de Los Andes y Fundación Omacha), donde se verificó, con ...herramientas moleculares, que varios lotes de tortugas matamata (Chelus fimbriata) decomisadas en la ciudad de Leticia, departamento del Amazonas, Colombia, correspondían a ejemplares capturados en la Orinoquia y cuyo destino final era aparentemente Perú, como parte de una red de tráfico de fauna. Basados en este hallazgo, 2 corporaciones liberaron 400 individuos neonatos en el en el río Bita y la Reserva Natural Privada Bojonawi en el departamento del Vichada, Orinoquia colombiana. Se evidencia el tráfico de esta especie probablemente hacia Perú, donde la comercialización de tortugas es legal. Se recomienda el uso de protocolos de identificación genética para determinar y controlar la procedencia geográfica de tortugas decomisadas a futuro, como paso previo y necesario para su liberación.
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