Peruvian nudibranchs (Mollusca, Gastropoda, Heterobranchia): an updated literature review-based list of species.

Nudibranchs, as a group, have received limited attention in terms of scientific study along the coastline of Peru. Here, an updated and comprehensive list of nudibranch species found in the Peruvian sea is presented, compiled through an extensive review of relevant literature. This compilation encompasses a total of 31 species, classified into two suborders, 10 superfamilies, 20 families, and 28 genera. With respect to the biogeographic provinces along the Peruvian coast, 23 species inhabit the Warm Temperate Southeastern Pacific province, 18 species occur in the Tropical Eastern Pacific province, and 10 species are found in both provinces, crossing the transitional zone between them. In terms of distribution patterns, two species exhibit a cosmopolitan distribution (Glaucusatlanticus and Fionapinnata), while two species display a circumtropical distribution (Cephalopygetrematoides and Phylliroebucephala). One species exhibits a bipolar distribution in the Eastern Pacific and possesses an amphi-South American distribution (Rostangapulchra). Additionally, six species exhibit an amphi-South American distribution (Rostangapulchra, Diaululapunctuolata, Dotouva, Tyrinnaevelinae, Tyrinnadelicata, and Dorisfontainii), and two species are endemic to Peru (Corambemancorensis and Felimaresechurana). This study provides comprehensive information on biogeographical aspects, geographical distributions, and taxonomic updates within the nudibranch species documented in Peru. Furthermore, we discuss the status of species listed in previous literature that have not been confirmed by collections, referring to them as potentially occurring species.

Comparative Mitogenome Analysis of Two Native Apple Snail Species (Ampullariidae, Pomacea) from Peruvian Amazon.

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.

Description of two new species of apple snail (Ampullariidae: Pomacea) from Peruvian Amazonia.

Two new species of apple snails are described, Pomacea penai sp. nov. and Pomacea reevei sp. nov. that are used as food resources in Peruvian Amazonia. We used anatomical and conchological features to diagnose these two species. Pomacea penai sp. nov. is characterized by a highly variable shell morphology, spire that is prominent to immersed, apical penis sheath gland covering 1/3 penis sheath and elongated basal gland, prostate broad proximally, reduced stomach septum, green eggs, and commonly inhabits temporary flooded areas, creeks, and oxbow lakes. Pomacea reevei sp. nov. possesses a large shell, ranging from 81-137 mm, grey broad penis sheath, small apical penis sheath gland and the basal gland covering 1/3 penis sheath, tall stomach septum, white eggs, and found in deep lentic water bodies.

From the Andes to the desert: 16S rRNA metabarcoding characterization of aquatic bacterial communities in the Rimac river, the main source of water for Lima, Peru.

The Rimac river is the main source of water for Lima, Peru's capital megacity. The river is constantly affected by different types of contamination including mine tailings in the Andes and urban sewage in the metropolitan area. In this work, we aim to produce the first characterization of aquatic bacterial communities in the Rimac river using a 16S rRNA metabarcoding approach which would be useful to identify bacterial diversity and potential understudied pathogens. We report a lower diversity in bacterial communities from the Lower Rimac (Metropolitan zone) in comparison to other sub-basins. Samples were generally grouped according to their geographical location. Bacterial classes Alphaproteobacteria, Bacteroidia, Campylobacteria, Fusobacteriia, and Gammaproteobacteria were the most frequent along the river. Arcobacter cryaerophilus (Campylobacteria) was the most frequent species in the Lower Rimac while Flavobacterium succinicans (Bacteroidia) and Hypnocyclicus (Fusobacteriia) were the most predominant in the Upper Rimac. Predicted metabolic functions in the microbiota include bacterial motility and quorum sensing. Additional metabolomic analyses showed the presence of some insecticides and herbicides in the Parac-Upper Rimac and Santa Eulalia-Parac sub-basins. The dominance in the Metropolitan area of Arcobacter cryaerophilus, an emergent pathogen associated with fecal contamination and antibiotic multiresistance, that is not usually reported in traditional microbiological quality assessments, highlights the necessity to apply next-generation sequencing tools to improve pathogen surveillance. We believe that our study will encourage the integration of omics sciences in Peru and its application on current environmental and public health issues.

Identificación molecular y relaciones evolutivas de Pomacea nobilis, base para la autenticación específica del churo negro de la Amazonia peruana / Molecular identification and evolutionary relationships of Pomacea nobilis, basis for the specific authentication of the black apple snail from Peruvian Amazonia

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.

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.