Gymnurid rays are found in tropical, subtropical, and temperate regions around the world, where they are associated with sandy or muddy bottoms in coastal areas, being easily distinguished from other ...rays by the width of the disc. In recent years, the systematics of this family have been revised extensively. However, there has been no comprehensive molecular review of the family based on an adequate sample of species and localities, which may have obscured the presence of distinct evolutionary lineages. The present study was based on samples of 12 of the 13 valid species of the genus Gymnura, which were used for a multilocus reconstruction of the evolutionary history of the family Gymnuridae. Our results indicate the existence of several cryptic gymnurid lineages, within the species Gymnura micrura, Gymnura lessae, Gymnura altavela, and Gymnura poecilura. Also, we indicate that only half of the species that compose the genus are known, as well their conservation status. The analyses also indicate that the gymnurids originated during the Paleocene, with events of dispersal and vicariance occurring through the formation of oceanographic barriers, and species diversification peaking during the Oligocene and Miocene. The results of the present study reinforce the need for a comprehensive revision of the systematics of the family, in particular, the widely distributed species that are considered valid taxa, but may, in fact, represent different cryptic species. The inadequate classification of this cryptic diversity may have negative implications for the development of effective conservation measures.
Summary of the hidden diversity of the species inside Gymnura, with the main biogeographical events that shape its origin and diversification.
The Southeast Pacific comprises two Large Marine Ecosystems, the Pacific Central-American Coastal and the Humboldt Current System; and is one of the less well known in the tropical subregions in ...terms of biodiversity. To address this, we compared DNA barcoding repositories with the marine biodiversity species for the Southeast Pacific. We obtained a checklist of marine species in the Southeast Pacific (i.e. Colombia, Ecuador, Chile, and Peru) from the Ocean Biodiversity Information System (OBIS) database and compared it with species available at the Barcoding of Life Data System (BOLD) repository. Of the 5504 species records retrieved from OBIS, 42% of them had at least one registered specimen in BOLD (including specimens around the world); however, only 4.5% of records corresponded to publicly available DNA barcodes including specimens collected from a Southeast Pacific country. The low representation of barcoded species does not vary much across the different taxonomic groups or within countries, but we observed an asymmetric distribution of DNA barcoding records for taxonomic groups along the coast, being more abundant for the Humboldt Current System than the Pacific Central-American Coastal. We observed high-level of barcode records with Barcode Index Number (BIN) incongruences, particularly for fishes (Actinopterygii = 30.27% and Elasmobranchii = 24.71%), reflecting taxonomic uncertainties for fishes, whereas for Invertebrates and Mammalia more than 85% of records were classified as data deficient or inadequate procedure for DNA barcoding. DNA barcoding is a powerful tool to study biodiversity, with a great potential to increase the knowledge of the Southeast Pacific marine biodiversity. Our results highlight the critical need for increasing taxonomic sampling effort, the number of trained taxonomic specialists, laboratory facilities, scientific collections, and genetic reference libraries.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Mulinia lateralis is a native bivalve from the Western Atlantic Ocean, distributed from the Gulf of Saint Lawrence in Canada to Yucatan in Mexico. Based on morphological and genetic data of specimens ...collected in shrimp farms, in this work, we confirm the presence of M. lateralis in the Gulf of Guayaquil, Ecuador. Presence and its consequences of this invasive bivalve in the region is discussed.
Apple snails of the genus Pomacea Perry, 1810 (Mollusca: Caenogastropoda: Ampullariidae) are native to the Neotropics and exhibit high species diversity, holding cultural and ecological significance ...as an important protein source in Peru. However, most genetic studies in Pomacea have focused mostly on invasive species, especially in Southeast Asia, where they are considered important pests. In this study, we assembled and annotated the mitochondrial genomes of two Pomacea species native to the Peruvian Amazon: Pomacea reevei Ampuero & Ramírez, 2023 and Pomacea aulanieri (Deville & Hupé, 1850). The mitogenomes of P. reevei and P. aulanieri comprise 15,660 and 16,096 bp, respectively, and contain the typical 37 genes of the animal mitochondria with a large control region of 292 bp in P. reevei and 524 bp in P. aulanieri—which fall within the range of what is currently known in Pomacea. Comparisons with previously published mitogenomes in Pomacea revealed differences in the overlapping of adjacent genes, the size of certain protein-coding genes (PCGs) and the secondary structure of some tRNAs that are consistent with the phylogenetic relationships between these species. These findings provide valuable insights into the systematics and genomics of the genus Pomacea.
Abstract The genus Urotrygon comprises small‐ to medium‐sized endemic round rays on the American continent and has undergone several synonymization processes. Here, we used an integrative taxonomic ...approach, including meristic, morphometric, and mtDNA analyses, to resolve the particularly intricate relationship among Urotrygon munda Gill, 1863, Urotrygon chilensis (Günther, 1872), and Urotrygon asterias (Jordan & Gilbert, 1883). The latter species is currently a synonym of U. munda but is also considered the U . chilensis “northern morphotype.” These taxonomic entities have historically been confounded, mainly due to their phenotypical resemblance along their geographic distribution in the eastern Pacific. We assessed 78 specimens (43 “northern” and 30 “southern morphotypes” of U. chilensis , as well as 5 U . munda ) using 19 external variables for taxonomic and morphometric analysis. Distinct meristic patterns, including pectoral and pelvic ceratotrichia, vertebrae number, and thorn distribution along the dorsal midline, were observed in the series‐type specimens of the three taxonomic entities. Our multivariate morphometric analyses consistently differentiated the three groups as distinct taxonomic entities, with an overall classification accuracy of 66.7%. The meristic results also provided reliable information distinguishing the three entities. Based on the nicotinamide adenine dinucleotide ( NADH 2 ) and cytochrome oxidase subunit I ( COI ) genes, our phylogenetic analysis were consistent with the morphometric and meristic data, supporting these three entities as distinct species having their own evolutionary lineages. Our comprehensive approach confidently demonstrated that the northern U . chilensis morphotype matched and corresponded to the description of the Starry round ray, U . asterias , confirming its taxonomic resurrection as a valid species distinct from U . chilensis and U . munda . The geographic distribution of U . asterias spans from the tropical west coast of Mexico (including the Gulf of California) to Costa Rica, revealing that microevolutionary processes have well‐defined population clades within this range. Furthermore, U . chilensis is unequivocally established as the sole Urotrygon species occurring south of the Guayaquil marine ecoregion. In addition, the public COI and NADH 2 sequences available for Urotrygon hosted in the ad hoc online databases were found to be misidentified, emphasizing the need for rigorous taxonomic scrutiny in this group. Finally, our research underscores the significance of an integrative approach that combines morphometric, meristic, and molecular techniques with historical data to disentangle the complexities of closely related taxa.
Currently, seven valid species are recognized in the genus Peprilus. Found from United States to Argentina, Peprilus paru has a complex nomenclatural history, with seven junior synonyms, three from ...North America and four from South America. As there has been no recent research, it remains unclear whether species representatives in the north-south axis represent different populations of a single species or distinct species. By comparison of type specimens as well as a comprehensive collection of non-type specimens, this paper aims to clarify the taxonomic status of the nominal species listed as junior synonyms of Peprilus paru in the Atlantic side of South America. Based on morphological data and DNA barcoding, Peprilus crenulatus Cuvier, 1829 and P. xanthurus (Quoy & Gaimard, 1825) are resurrected, while Rhombus argentipinnis Cuvier, 1833 and Rhombus orbicularis Guichenot, 1866, are considered to be junior synonyms of P. crenulatus.
Angel sharks are distributed worldwide in tropical to subtropical waters. Across the Eastern Pacific Ocean (EPO), two valid species are reported: The Pacific angelshark Squatina californica and the ...Chilean angelshark Squatina armata; however, there is still uncertainty about their geographic distribution, mainly along the northern Peru coast where the species have been reported to be sympatric. The aim of this study is to describe the genetic differences between the genus Squatina from the EPO, including samples from northern Peru, and using DNA barcoding and three species delimitation models: Poisson tree processes (PTP) model, Bayesian implementation of the PTP (bPTP) model and the general mixed Yule coalescent (GMYC) model. The three approaches summarized 19 nominal Squatina species in 23 consensus Molecular Taxonomic Units (MOTU). Only 16 of them were in accordance with taxonomic identifications. From the EPO, four Squatina MOTUs were identified, one from North America (S. californica USA/Mexico) and three sampled in northern Peru, S. californica Peru, S. armata and Squatina sp. (a potential new species). This study contributes to the management and conservation policies of angel sharks in Peru, suggesting the presence of an undescribed species inhabiting the northern Peruvian coast. The use of molecular approaches, such as DNA barcoding, has the potential to quickly flag undescribed species in poorly studied regions, including the Southeast Pacific, within groups of ecologically and economically important groups like angel sharks.
A combination of a RADseq method (ddRAD) with long read high throughput sequencing (Roche 454) was tuned up in order to identify and validate a set of SNPs useful for gene diversity analysis in two ...important South American commercial tuna (Thunnus albacares and Scomberomorus brasiliensis). A total of 11 and 21 individuals of T. albacares and S. brasiliensis, respectively, were used for SNP identification. DNA was individually digested with two restriction enzymes (SbfI and SphI) and fragments between 300 and 600bp selected. Combinatorial barcoding was used to identify individuals by including short sequences (5–7bp) in the adaptors of each restriction site (P1 and P2). After adaptor ligation, samples were pooled and size-selected, amplified by PCR, and sequenced on a 454 GS-Junior sequencer. A total of 180,779 reads were produced with an average length and coverage of 287bp and 26x, respectively. Sets of 60 and 79 SNPs were in silico selected for T. albacares and S. brasiliensis, respectively, and were tested and validated in 74 and 66 individuals, respectively, on a MassARRAY platform. A total of 36 and 47 SNPs were polymorphic and useful for population analysis. A preliminary study on two distant Brazilian populations of both species (∼3000km) with these SNPs suggested the absence of significant structure among local populations of both species. Our results demonstrate the possibility of combining ddRAD with long read high throughput sequencing for marker development in species with scarce genomic resources.
The largetooth sawfish (Pristis pristis) is listed as Critically Endangered on the IUCN Red List (Kyne et al. 2013). This species has been recorded in the Eastern Tropical Pacific, where its range ...has been described as extending from Mazatlan, Mexico, to northern Peru (Chirichigno Cornejo 2001). Recent research efforts suggest that largetooth sawfish are now extremely rare or locally extinct on Mexico's Pacific coast (Bonfil et al. 2018). There is no current information on the status of largetooth sawfish in Panama or Colombia; the most recent record of a largetooth sawfish captured on Colombia's Pacific coast occurred in 2007 (Chasqui et al. 2017). In Ecuador, the species had been considered extirpated. However, in 2014, a large largetooth sawfish was captured by local fisherman in southern Ecuador, taken to the fishing port of Salinas and then released by the environmental agency (Barriga 2012; Rosas-Luis 2014). In Peru, recent reports of largetooth sawfish have been rare, but two captures of largetooth sawfish by fishermen (2014 and 2015) in northern Peru were reported (Mendoza et al. 2017). This confirms that the species is still occasionally encountered in this region.
The Labridae is a species-rich family of colorful fishes distributed globally in different habitats. Polylepion cruentum was described based on type material collected from the Gulf of California, ...and Quepos, Pacific coast of Costa Rica. It has since been reported from several other localities, including Mexico to Nicaragua and the Cocos Island. Recent collecting efforts in Northern Peru yielded an unusual species of labrid with uncertain taxonomic identity. Measurements, counts, coloration (in life and preserved) and DNA barcoding of the specimen agrees well with Polylepion cruentum. This represents the first record of the species from Northern Peru (Acapulco, Tumbes Department) and South America. The expansion of the distribution range of this species is perhaps due to the input of warm waters to Northern Peru, increasing especially during El Niño events. This new record is important to include in future marine checklists and consequently evaluate the conservation status of this species in Peru.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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