RESUMO
Monogeneans are flatworm parasites that infest fish gills primarily but can also infect various other vertebrates, including amphibians, aquatic reptiles, mammals like hippos, and occasionally invertebrates like copepods, isopods, and cephalopods. Despite their remarkable diversity, our knowledge of monogenean parasites in Peru remains significantly limited, resulting in substantial gaps in our comprehension of their taxonomic identities, host associations, and geographic distribution. To address these knowledge deficits, we present an extensively curated checklist of monogeneans associated with aquatic vertebrates in Peru. This comprehensive compilation is derived from meticulous literature surveys, the examination of specimens deposited in both international and national collections, and the inclusion of additional freshly collected specimens. The checklist offers a thorough repository of data encompassing the diversity, host associations, and geographical distribution of these parasites. Taxonomic discrepancies are addressed through a critical review of the existing literature, supplemented by the direct examination of specimens, including type or voucher specimens, deposited within scientific collections. Additionally, we provide data on the DNA sequences of individual taxa. The compiled list comprises records of 358 monogenean species, including 270 valid species and 88 taxa identified at the family or generic level, all reported across 145 host species in Peru. Predominantly, these parasitic species exhibit associations within fish, with 335 infecting teleosts and 20 affecting chondrichthyans. Three monogenean species have been documented as infecting amphibians, namely Mesopolystoma samiriensis, Polistoma sp. and Wetapolystoma almae. Among the monogeneans reported, 141 were found in marine environments and 214 in freshwater environments. The most diverse families were Dactylogyridae and Diplectanidae, comprising 217 and 24 species, respectively. The hosts that harbored the highest number of monogeneans were Pygocentrus nattereri (with 23 species), followed by Stellifer minor (13 spp.) and Triportheus angulatus (11 spp.). We detected many species that do not have any material deposited in a scientific collection due to the loss or deactivation of the collection. These findings represent only a fraction of the potential diversity, considering the wide variety of aquatic vertebrate hosts inhabiting the tropical and subtropical regions of Peru.
RESUMO
Abstract In this study, a new species of Monogenoidea, Cosmetocleithrum amazonensis n. sp., parasitizing the gills of the silurid Auchenipterichthys coracoideus (Eigenmann & Allen, 1942), is documented. Cosmetocleithrum amazonensis n. sp. is distinguished from all other congeners by possessing an elongated, sclerotized, and sinuous male copulatory organ (MCO) with poorly defined spirals, a sclerotized border at the base, and the distal region supported by the accessory piece. The accessory piece is a single, robust, and non-articulated plate with the MCO. This study presents the third record of a Monogenoidea species in an Auchenipteridae (Siluriformes) host from Peru.
Resumen En este trabajo se registra una nueva especie de Monogenoidea, Cosmetocleithrum amazonensis n. sp., parasitando las branquias del silurido Auchenipterichthys coracoideus (Eigenmann & Allen, 1942). Cosmetocleithrum amazonensis n. sp. se distingue de todas las demás especies congéneres por poseer un órgano copulador masculino (OCM) tubo alargado, esclerotizado y sinuoso, con espirales poco definidos, base con borde esclerotizado y con la región distal apoyada sobre la pieza accesoria. La pieza accesoria es una placa única, robusta y no articulada con el OCM. En este estudio se presenta el tercer registro de una especie de Monogenoidea en un hospedero Auchenipteridae (Siluriformes) del Perú.