Mining natural history collections: a new species of Neoechinorhynchus (Acanthocephala: Neoechinorhynchidae) parasitizing hogchokers (Achiridae) from the Amazon River in Peru

During a taxonomic study of the acanthocephalans deposited in the Helminthological Collection of the Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic, specimens of a new species of Neoechinorhynchus were found. These specimens, collected from Trinectes maculatus (Bloch & Schneider) (Achiridae) in the Peruvian Amazon, are morphologically and genetically characterized. Neoechinorhynchus pearljami sp. nov. is the first native species of Neoechinorhynchus from Peru. The new species is distinguished from its closest congeners from South America by a unique combination of morphological features, including its body size and shape, number of giant nuclei in the body wall, size of proboscis hooks, shape of the proboscis and lengths of the proboscis receptacle, lemnisci, testes, and cement gland. Molecular data based on newly generated sequences of nuclear ribosomal RNA (18S, 28S and ITS1–5.8S–ITS2) and mitochondrial (cox1 and 16S) genes support its distinctiveness within the genus. In addition, we provide new cox1 sequences for N. (N.) golvani Salgado-Maldonado, 1978, from Vieja fenestrata (Günther) (Cichlidae) in Mexico and 18S and 28S sequences for an unidentified Neoechinorhynchus species from Gobius niger L. (Gobiidae) in Finland. This study expands the known diversity and geographic range of Neoechinorhynchus in South America and provides valuable genetic data for future phylogenetic analyses of these acanthocephalans. It also supports the importance of depositing molecular vouchers (i.e., whole acanthocephalans or tissue samples preserved in 95–100% ethanol), into publicly accessible natural history collections. https://zoobank.org/urn:lsid:zoobank.org:pub:63B36985-4AAF-4FB7-A235-A60C785C9D2D