Abstract 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 the first ichthyofauna species inventory of the Yarinacocha lake, sampling throughout the entire lake during the rainy and dry seasons and considering also all previously recorded species deposited in the Ichthyological Collection of the MUSM with the same locality. A total of 164 fish species were recorded, representing 10 orders (plus Eupercaria), 34 families and 116 genera. Characiformes was the order with more species (68 spp., 41.5%) followed by Siluriformes (59 spp., 36%), Cichliformes (17 spp., 10.5%), and Gymnotiformes (8 spp., 4.9%). The most highly represented families, including almost 55.5% of the total diversity obtained, were Characidae (23 spp., 14%), followed by Cichlidae (17 spp., 10.4%), Loricariidae (14 spp., 8.5%), Pimelodidae (13 spp., 7.9%), Doradidae (13 spp., 7.4%) and Anostomidae (12 spp., 7.3%). From the total fish species recorded in this study, only 22 are considered protected species following the IUCN criteria and 109 species have commercial importance, including 90 ornamental species (54.8%). Our results contribute to the knowledge of the ichthyofauna of the Yarinacocha lake and can be used as a starting point for its conservation and sustainable management over time.

Resumo O lago Yarinacocha é um ecossistema emblemático da Amazônia peruana, representando o principal ponto de desembarque de peixes e também uma atração turística da cidade de Pucallpa. A grande diversidade faunística nesta área a tornou alvo de vários estudos, embora para as espécies de peixes a maioria deles tenha sido focada em espécies comerciais. Neste trabalho, realizamos o primeiro inventário da ictiofauna do lago Yarinacocha, amostrando todo o lago durante as estações chuvosa e seca, e também considerando todas as espécies depositadas na Coleção Ictiológica do MUSM dessa localidade. Um total de 164 espécies de peixes foram registradas, representando 10 ordens (mais Eupercaria), 34 famílias e 116 gêneros. Characiformes foi a ordem com mais espécies (68 espécies, 41,5%), seguida por Siluriformes (59 espécies, 36%), Cichliformes (17 espécies, 10,5%) e Gymnotiformes (8 espécies, 4,9%). As famílias mais representadas, incluindo quase 55,5% da diversidade total obtida, foram Characidae (23 spp., 14%), seguido por Cichlidae (17 spp., 10,4%), Loricariidae (14 spp., 8,5%), Pimelodidae (13 spp., 7,9%), Doradidae (13 spp., 7,4%) e Anostomidae (12 spp., 7,3%). Do total de espécies de peixes registradas neste estudo, apenas 22 são consideradas espécies protegidas seguindo os critérios da IUCN e 109 espécies têm importância comercial, incluindo 90 espécies ornamentais (54,8%). Nossos resultados contribuem para o conhecimento da ictiofauna do lago Yarinacocha e podem ser utilizados como ponto de partida para sua conservação e manejo sustentável ao longo do tempo.

Resumo Schizodon engloba aproximadamente 15 espécies de peixes neotropicais. A taxonomia integrativa, combinando análises moleculares e morfométricas com métodos taxonômicos tradicionais, foi utilizada para investigar Schizodon vittatus e sua potencial espécie irmã. As diferenças moleculares (DNA barcoding) entre as duas espécies são maiores do que a variação intraespecífica observada em espécies congêneres, e as duas espécies representam linhagens distintas por aproximadamente um milhão de anos. As duas espécies são morfologicamente muito similares e os dados merísticos mostram grande sobreposição. As análises morfométricas também mostraram sobreposição entre as duas espécies, mas indicaram diferenças na altura do pedúnculo caudal, no diâmetro interorbital, e no comprimento dos raios da nadadeira anal. O padrão de colorido parece fornecer uma característica diagnóstica clara para as duas espécies. Schizodon vittatus normalmente possui quatro faixas escuras transversais no corpo e sua espécie irmã tem três faixas, com a quarta, se presente, inconspícua e dorsal à linha lateral. Schizodon vittatus é redescrita com base no tipo e em espécimes coletados recentemente; sua localidade tipo é revisitada e a sua distribuição conhecida é restringida às drenagens do Araguaia e Tocantins. A nova espécie, irmã de S. vittatus e distribuída nas drenagens do Xingu e Tapajós, é descrita. Uma chave para a identificação das espécies do clado amazônico de Schizodon é apresentada.

Abstract Schizodon encompasses approximately 15 species of Neotropical headstanding fishes. Integrative taxonomy, combining molecular and morphometric analyses with traditional taxonomic methods, was used to investigate Schizodon vittatus and its potential new sister species. Molecular differences between the two species in the barcode are greater than intra-specific variation recovered in species of Schizodon, and the two species represent distinct lineages for approximately one million years. The two species are morphologically very similar, and the meristic data showed great overlap. Morphometric analyses also showed overlap among the putative species but indicated differences in caudal-peduncle depth, orbital diameter, and length of anal-fin rays. Color pattern seems to provide a clear diagnostic feature for the two species. Schizodon vittatus usually has four dark brown transversal bars on body, and its sister species has three conspicuous bars, with the fourth, if present, inconspicuous and dorsal to the lateral line. Schizodon vittatus is redescribed based on the type and recently collected specimens, its type locality is revisited, and its known distribution restricted to the Araguaia and Tocantins drainages. The new species, sister to S. vittatus, distributed in the Xingu and Tapajós drainages, is described. A key for the identification of the Amazon clade species of Schizodon is provided.

Abstract In the Peruvian Amazon, freshwater snails of the Ampullariidae family are known as churos, and around 20 species have originally been described for Peru. Although they are widely used for food, traditional medicine and the object of many studies for their cultivation and industrialization, only the species Pomacea maculata is mentioned in the literature. Molecular identification was carried out based on the mitochondrial marker COI of individuals of "churo negro" apple snails (Pomacea) commercialized in the markets of Iquitos, as well as those used in restaurant dishes in the city of Lima, and contrasted with specimens from their natural habitat. It was found that these specimens, correspond to the species Pomacea nobilis (Reeve, 1856). The molecular phylogenetic analysis showed P. nobilis as the sister species of P. guyanensis, in the P. glauca group, distantly related to P. maculata. The uncorrected distances found between them, for the mitochondrial marker COI, were from 11.33% to 13.17%, while with P. maculate were from 13.67% to 15.33%. These results demonstrated the effectiveness of the DNA barcode for the identification and authentication of the species, which gives it added value for its eventual export trade.

Resumen En la Amazonia Peruana los caracoles dulceacuícolas de la familia Ampullariidae son conocidos como churos y originalmente han sido descritas para Perú alrededor de 20 especies. Aunque son muy usadas para alimentación, medicina tradicional y objeto de muchos estudios para su cultivo e industrialización, solamente es mencionada en la literatura la especie Pomacea maculata. Se llevó a cabo la identificación molecular sobre la base del marcador mitocondrial COI, de individuos de churos negros (Pomacea) comercializados en los mercados de Iquitos, así como los usados en platos a la carta en la ciudad de Lima, contrastados con otros individuos de procedencia de su hábitat natural. Se encontró que estos especímenes expendidos corresponden a la especie Pomacea nobilis (Reeve, 1856). El análisis filogenético molecular mostró que P. nobilis es especie hermana de P. guyanensis, en el grupo de P. glauca, distantemente relacionada de P. maculata. Las distancias no corregidas encontradas entre ellas, para el marcador mitocondrial COI, fueron de 11.33% a 13.17%, mientras que con P. maculata fueron de 13.67% a 15.33%. Estos resultados demostraron la eficacia del código de barras de ADN para la identificación y autenticación de la especie, lo que le da un valor agregado para su eventual comercio de exportación.

Bostryx is largely distributed in Andean Valleys and Lomas formations along the coast of Peru and Chile. One species, Bostryx aguilari, is restricted to Lomas formations located in the Department of Lima (Peru). The use of genetic information has become essential in phylogenetic and population studies with conservation purposes. Considering the rapid degradation of desert ecosystems, which threatens the survival of vulnerable species, the aim of this study was, first, to resolve evolutionary relationships within Bostryx and to determine the position of Bostryx within the Bulimulidae, and second, to survey the genetic diversity of Bostryx aguilari, a species considered rare. Sequences of the mitochondrial 16S rRNA and nuclear rRNA regions were obtained for 12 and 11 species of Bulimulidae, respectively, including seven species of Bostryx. Sequences of the 16S rRNA gene were obtained for 14 individuals (from four different populations) of Bostryx aguilari. Phylogenetic reconstructions were carried out using Neighbor-Joining, Maximum Parsimony, Maximum Likelihood and Bayesian Inference methods. The monophyly of Bostryx was not supported. In our results, B. solutus (type species of Bostryx) grouped only with B. aguilari, B. conspersus, B. modestus, B. scalariformis and B. sordidus, forming a monophyletic group that is strongly supported in all analyses. In case the taxonomy of Bostryx is reviewed in the future, this group should keep the generic name. Bostryx aguilari was found to have both low genetic diversity and small population size. We recommend that conservation efforts should be increased in Lomas ecosystems to ensure the survival of B. aguilari, and a large number of other rare species restricted to Lomas.