Hernán Ortega

National University of San Marcos | UNMSM

Our study focuses on the fish fauna in the lower Pisco River in Ica, central coast of Perú. We examined the specimens deposited in the MUSM Ichthyological Collection including field evaluations in the main channel of the Pisco River, the Pisco Playa Wetland, the Morón Lagoon, and the Poza Lagunillas, as well as records from the available literature...

El estudio muestra elevadas tasas de colonización por comunidades acuáticas en pozas mineras abandonadas. Peces, aves, plantas acuáticas, fitoplancton, anfibios, chinches, libélulas y escarabajos demostraron la capacidad de colonizar pozas mineras abandonadas. En algunos casos, la riqueza de especies alcanzó niveles comparables a lagunas naturales....

The Yarinacocha lake is an emblematic ecosystem of the Peruvian Amazon, representing the main point of fish landing and a tourist attraction in the city of Pucallpa. The wide fauna diversity in this area has made it the target of various studies, although for fish species most of them were focused on commercial species. In this work, we carried out...

To update the knowledge of the ichthyofauna of the Tumbes River basin, we provide a list of species. We report 47 species of fishes, grouped into 23 families and 11 orders. Characiformes was the most diverse order with 12 species (25.5% of the total richness), followed by Carangiformes with eight species (17%). In our study, two species are newly r...

DNA barcoding has been used successfully in fish species identification and cryptic diversity detection, expanding knowledge about Neotropical ichthyofauna. Yarinacocha is a oxbow lagoon, which seasonally forms part of the Ucayali River, a tributary of the Amazon River. It is an important area for tourism, commercial fishing, and the extraction of...

En este trabajo se presenta una lista actualizada de los registros de especies de peces de la cuenca del río Ucayali, Perú, provenientes de datos publicados y no publicados. Los resultados muestran que la cuenca del Ucayali presenta una ictiofauna rica y diversificada con el registro de 734 especies distribuidas en 15 órdenes, 49 familias y 292 gén...

Chira River is located on the north coast of Peru. The scant information of the ichthyofauna from coastal drainages from Peru is noteworthy. The aim of this study is to characterize the ichthyofauna along the Chira River basin in terms of diversity and altitudinal range distribution. The material examined belongs to the Ichthyological collection of...

The doncella Pseudoplatystoma punctifer is an economically and ecologically important catfish in the Amazon basin. However, little is known about its age, growth and population dynamics parameters. This study aims to validate the formation of growth marks in vertebrae of individuals collected from two rivers systems of the Peruvian Amazon (Amazon-M...

To date, more than 2400 valid fish species have been recorded in the Amazon basin. However, some regions remain poorly documented. This is the case in the Beni basin and in particular in one of its main sub-basins, the Tuichi, an Andean foothills rivers flowing through the Madidi National Park in the Bolivian Amazonia. The knowledge of its ichthyol...

This study presents an extensive review of published and unpublished occurrence records of fish species in the Loreto department. Located in the northeast of the country, Loreto is the most geographically extensive region in the Peruvian territory. Despite the increase in fish collections in Loreto in recent years, the ichthyofauna of this departme...

Aim Phylogenetic relatedness among species can provide useful information on the diversification history and past dispersal events that may have shaped contemporary assemblages. Here, using of the most comprehensive fish occurrence database currently available and a global molecular phylogeny of ray-finned fishes, we evaluate the respective roles o...

Aim: Community phylogenetics provides important information about the evolutionary and ecological factors help structure regional species assemblages. Here, we analyze phylogenetic diversity (phylodiversity) patterns among fish species in 97 sub-drainages of the Amazon basin, to evaluate the roles of historical and contemporary processes in generat...

• The Amazon basin has been subjected to extreme climatic events and according to climate change projections this hydrosystem could face changes in the natural dynamic of flood cycles that support the feeding and reproduction of many fish species, threatening aquatic biodiversity. • Protected areas (PAs) are the main tools used to safeguard the bio...

Upstream range shifts of freshwater fishes have been documented in recent years due to ongoing climate change. River fragmentation by dams, presenting physical barriers, can limit the climatically induced spatial redistribution of fishes. Andean freshwater ecosystems in the Neotropical region are expected to be highly affected by these future distu...

Mastiglanis is a genus of heptapterid catfish represented by two valid species. These freshwater species are widely distributed along the Amazon, Orinoco, and Maroni River basins. However, a taxonomic review of specimens collected in the Putumayo and Nanay rivers, Amazon River basin in Peru revealed a new species of Mastiglanis. A morphological ana...

Here we explore the use of community phylogenetics as a tool to document patterns of biodiversity in the Fitzcarrald region, a remote area in Southwestern Amazonia. For these analyses, we subdivide the region into basin-wide assemblages encompassing the headwaters of four Amazonian tributaries (Urubamba, Yuruá, Purús and Las Piedras basins), and ha...

The Amazon Basin is an unquestionable biodiversity hotspot, containing the highest freshwater biodiversity on earth and facing off a recent increase in anthropogenic threats. The current knowledge on the spatial distribution of the freshwater fish species is greatly deficient in this basin, preventing a comprehensive understanding of this hyper-div...

Conserving freshwater habitats and their biodiversity in the Amazon Basin is a growing challenge in the face of rapid anthropogenic changes. We used the most comprehensive fish‐occurrence database available (2355 valid species; 21,248 sampling points) and 3 ecological criteria (irreplaceability, representativeness, and vulnerability) to identify bi...

The Amazon Basin is an unquestionable biodiversity hotspot, containing the highest freshwater biodiversity on earth and facing off a recent increase in anthropogenic threats. The current knowledge on the spatial distribution of the freshwater fish species is greatly deficient in this basin, preventing a comprehensive understanding of this hyper-div...

Varicharax nigrolineatus, a new genus and species of stevardiine fish, is described from the Río Amazonas basin, Peru, based on a comprehensive phylogenetic comparison with other characids. Two data sets (A: combined morphological and molecular matrix, 474 species and 6,653 characters; B: morphological matrix, 216 species and 524 characters) were u...

Se revisa el estado taxonómico de Gastrotheca peruana usando métodos loge- né cos en base a secuencias de 16S rRNA. Los árboles de máxima verosimilitud y Bayesiano mostraron que las variantes génicas de G. peruana forman dos clados que no son hermanos. Uno de estos clados se distribuye en el norte de Perú, incluyendo un individuo procedente de la l...

The largest collection of freshwater fishes in Peru is located at Lima, in the Museo de Historia Natural of the San Marcos University (MUSM). It houses more than 60 thousand lots representing most of the diversity of fishes, with samples from main basins in the country. We invite you to learn more about this important scientific heritage.

Using the most comprehensive fish occurrence database, we evaluated the importance of ecological and historical drivers in diversity patterns of subdrainage basins across the Amazon system. Linear models reveal the influence of climatic conditions, habitat size and sub-basin isolation on species diversity. Unexpectedly, the species richness model a...

Using the most comprehensive fish occurrence database, we evaluated the importance of ecological and historical drivers in diversity patterns of subdrainage basins across the Amazon system. Linear models reveal the influence of climatic conditions, habitat size and sub-basin isolation on species diversity. Unexpectedly, the species richness model a...

The title "AMAZON FISH database" is a working title for the Amazonian Freshwater Fish Biodiversity database that was constructed in the framework of the AMAZON FISH (ERANetLAC/DCC-0210) project. In order to construct the AMAZON FISH database, which aims to become a high quality freshwater fish biodiversity database covering the entire Amazon draina...

• Assessing the effectiveness of protected areas for sustaining species and identifying priority sites for their conservation is vital for decision making, particularly for freshwater fishes in South America, the global centre of freshwater fish diversity. Several conservation planning studies have used threatened freshwater fishes or species that...

Banded Knifefishes (Gymnotus, Gymnotidae) comprise the most species-rich genus of Neotropical electric fishes, with 41 species currently described from throughout the humid Neotropics, from Mexico to Argentina. Despite substantial alpha -taxonomic work in recent years, the diversity of Gymnotus in some regions remains poorly understood. Here we des...

The Astyanax orthodus species-group includes nine species: Astyanax boliviensis sp. nov., A. bopiensis nom. nov., A. embera sp. nov., A. gandhiae sp. nov., A. moorii comb. nov., A. orthodus, A. superbus, A. villwocki and A. yariguies comb. nov. The group is diagnosed by the presence of a series of pinnate-shaped marks (chevrons) located along the l...

Andes-to-Amazon river connectivity controls numerous natural and human systems in the greater Amazon. However, it is being rapidly altered by a wave of new hydropower development, the impacts of which have been previously underestimated. We document 142 dams existing or under construction and 160 proposed dams for rivers draining the Andean headwat...

El estudio presenta una lista comentada de especies de peces registradas en la cuenca del río Aguaytía. Son consideradas las colectas de diferentes años y estaciones climáticas entre 1942 y 2009. Es el primer inventario de los peces para esta cuenca, la cual es importante para el Parque Nacional Cordillera Azul. La metodología empleada para la reco...

Molecular studies have improved our knowledge on the neotropical ichthyofauna. DNA barcoding has successfully been used in fish species identification and in detecting cryptic diversity. Megaleporinus (Anostomidae) is a recently described freshwater fish genus within which taxonomic uncertainties remain. Here we assessed all nominal species of this...

Initial Data Management Plan for the Amazonian Freshwater Fish Biodiversity database that will be constructed in the framework of the AMAZONFISH (ERANetLAC/DCC-0210) project.

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009;...

This plot is not part of the published stance but derives from it. The plot shows the number of authors by geographic region (courtesy of Dr. Diego Astua).

La familia Potamotrygonidae en Loreto (Perú), es objeto de una pesquería de importancia económica y ademáses poco conocida desde el punto de vista científico. Por lo anterior, se evaluó la riqueza, distribución, aspectos ecológicos, pesqueros y amenazas, en rios Nanay, Itaya y Amazonas (julio–octubre 2013). Los hábitats acuáticos se describieron li...

El agua es considerada como uno de los recursos naturales más esenciales para la vida. Esto se ve relejado en el hecho de que el agua es el elemento común a la mayoría de los Objetivos de Desarrollo Sostenible de las Naciones Unidas. Así, el agua conecta la salud pública, la seguridad alimentaria, la energía para todos, el bienestar del medio ambie...

This species is listed as Vulnerable because it has a very restricted distribution (known only from two locations) and there is the potential for mining activities and construction of dams that may drive it to CR or EX in the near future.

Although this species has a very restricted distribution, it occurs in a remote and well-preserved area and there are no known major threats affecting it. Therefore, it is listed as Least Concern.

This species is listed as Vulnerable because it has a very restricted distribution (known only from one location) and there is the potential for mining activities and construction of dams that may drive it to CR or EX in the near future.

This species is listed as Data Deficient because the locality where the species was originally collected is uncertain

Although this species has a very restricted distribution, its population is presumed to be stable and there are no known major threats affecting it.

This species has a very restricted distribution (area of occupancy (AOO) = 9 km²) and it occurs at only one location that is being affected by deforestation for livestock raising, which is causing a continuous decline in the quality of its habitat due to erosion and sedimentation. The species is also being collected for the ornamental trade, sugges...

This species is listed as Least Concern because its population is presumed to be stable and there are no known major threats affecting it.

This species is assessed as Least Concern because it has a wide distribution, is common, and there are no known major threats currently affecting it.

With around 15% of all described freshwater fish species in the world, the Amazon Basin is by far the most fish species-rich freshwater ecosystem on the planet. In this opinion paper, a rough evaluation is given on just how vulnerable Amazonian freshwater fishes are to ongoing climate change. And to argue that current anthropogenic threats through...

This species occurs in the Amazon basin in Peru (Ortega et al. 2012), in the upper Tulumayo River and the upper Paucartambo River, in the Junín and Pasco departments respectively; in the upper Ucayali River basin (Salcedo 2007). It occurs at elevations between 1,000 and 1,500 m (Salcedo 2007). Its type locality is the Tullumayo [Tulumayo] River in...

This species is known only from its type locality in the Huallaga River near Tingo María, Leoncio Prado province, Huánuco Department, Peru (Salcedo 2006). The EOO is 160 km² (calculated as the minimum convex polygon around the sub-catchment(s) where the species occurs) and it is inferred that the species occurs in no more than five locations, based...

This species occurs in the Upper Huallaga River in Tingo María (650 m asl), in Huánuco, Peru (Salcedo 2006). Its type locality is in the vicinity of Tingo María, backwater near Puerto Nuevo, flowing into the Tullamaya River, Huánuco Department, Peru (Salcedo 2006). The EOO is 160 km² (calculated as the minimum convex polygon around the sub-catchmen...

This species is endemic to Peru, where is known from three main areas: the Upper Chamaya River basin in the high part of the drainage of the Marañón River (Froese and Pauly 2013, Ortega et al. 2012), the Upper Cenepa and Huachi Rivers (ichthyological collection, MHN-UNMSM), and from its type locality in the Chota River [Chotano], Cajamarca, (1,465-...

This species is endemic to Peru, where it is known from the type locality only in the Huallaga River near Tingo María (Salcedo 2006) in the Peruvian Amazon (Ortega et al. 2012). The EOO has been estimated at 340 km² (calculated as the minimum convex polygon around the known sub-catchment(s) where the species occurs), and it is assumed to occur in f...

This species is so far known only from its type locality in the Jequetepeque River, just to the west of Chilete (Cajamarca and La Libertad) in the Peruvian Amazon (Silfvergrip 1996, Ortega et al. 2012, Bockmann 2003). Its area of occupancy (AOO) has been estimated to be 9 km² (using a 3 x 3 km grid cell). The species occurs in only one location, ba...

Raya Amazonica Potamotrygon tigrina has most recently been assessed for The IUCN Red List of Threatened Species in 2014. Potamotrygon tigrina is listed as Endangered under criteria B1ab(iii,v).

Una distintiva especie de Chaetostoma fue descubierta en los tributarios de montaña del río Marañón, Perú. La nueva especie se diferencia de todas las otras especies de Chaetostoma descritas por tener un mechón de odontodes, rodeado por piel desnuda, en el medio de cada placa dermal lateral del tronco, y más de 20 odontodes hipertrofiados evertible...

With around 15% of all described freshwater fish species in the world, the Amazon Basin is by far the most fish species-rich freshwater ecosystem on the planet. In this opinion paper, a rough evaluation is given on just how vulnerable Amazonian freshwater fishes are to ongoing climate change. And to argue that current anthropogenic threats through...

Chrysobrycon yoliae, new species, is described from a drainage flowing into the río Yucamia basin, río Ucayali basin, Peru. Chrysobrycon yoliae is readily distinguished from its congeners by the anterior tip of pelvic bone situated anterior to the fifth rib (vs. situated posterior to the fifth rib), the presence of 20-26 dentary teeth (vs. 11-19),...

Resumen Los ecosistemas acuáticos tropicales son poco conocidos en relación a otros medios templados o fríos. Asimismo, el efecto de los impactos humanos sobre estos ecosistemas y su biodiversidad han sido poco abordados en la literatura científica. En este trabajo se analizan las características limnológicas básicas de ocho cuerpos de agua (quebra...

Resumen Los ecosistemas acuáticos tropicales son poco conocidos en relación a otros medios templados o fríos. Asimismo, el efecto de los impactos humanos sobre estos ecosistemas y su biodiversidad han sido poco abordados en la literatura científica. En este trabajo se analizan las características limnológicas básicas de ocho cuerpos de agua (quebra...

Con el 15% de todos los peces de agua dulce descritos en el mundo, la cuenca amazónica es el sistema de agua dulce más biodiverso del planeta. Hoy en día, losfactores principalesde degradaciónde los ecosistemas deagua dulceen la regiónamazónica son la rápida expansión de las infraestructuras y actividades económicas. Estas perturbaciones provocan i...

Hyphessobrycon with 129 valid species, is a genus of fish that has a great diversity of species in the Neotropical ichthyofauna, reaches its greatest diversity in the Amazon basin with about 70% of these species, is highly desired by hobbyists because of their beauty and color, and are still meeting new species. We analyzed specimens from the Depar...