New Species of Cosmetocleithrum (Monopisthocotyla: Dactylogyridae) from Centromochlus Heckelii (Osteichthyes: Auchenipteridae) from the Itaya River, Peru.

INTRODUCTION

Studies concentrating on description, identification, and analysis of monogenoids are required to further our understanding of this group of parasites connected to Amazonian fish. Based on the above, the main objective of this research was to identify new species of monogenoids in the gills of Centromochlus heckelii (De Filippi, 1853) (Siluriformes: Auchenipteridae) collected in the Itaya river, Loreto-Peru.

MATERIALS AND

METHODS

Two hundred and forty specimens of C. heckelii were collected in the Itaya River (3°47'20.70"S 73°15'40.90"W), Loreto, Peru in March 2025. The collected fish were transported in boxes with ice to the laboratory for parasitological analyses.

RESULTS

Three species of monogeneans of the family Dactylogyridae were registered, two new species and one previously known: Demidospermus centromochlii Mendoza-Franco & Scholz, 2009 which is proposed to be reassigned into Cosmetocleithrum Kritsky, Thatcher & Boeger, 1986 due to morphological characteristics. The new species Cosmetocleithrum itayensis n. sp. and Cosmetocleithrum iiapensis n. sp. are similar by presenting the MCO as a sigmoid tube and a seed-shaped accessory piece, but they differ from each other in the shape of the MCO, accessory piece, vagina, and the size of the anchors and of the submedial projections in dorsal bar.

CONCLUSIONS

The results of the present investigation represent the second report of parasites in C. heckelii, with the discovery of two new dactylogyrid species. This increases the knowledge of the biodiversity of monogenoids reported for Peru and the Neotropical region.