Monogenea on exotic Indian freshwater fish. 8. Co-translocation of Cichlidogyrus tilapiae (Monogenea, Dactylogyridae) with pindani Chindongo socolofi (Cichliformes, Cichlidae), the first report of this parasite genus in India

Chindongo socolofi (Cichliformes, Cichlidae) is a popular freshwater ornamental fish from Lake Malawi in Africa. Although identifying parasites associated with the global ornamental trade is critical for developing biosecurity practices, little is known about the parasite fauna of C. socolofi. Therefore, this study sought to determine what monogenean parasites C. socolofi harbours in India. Adult specimens of this host species were collected from various aquarium shops across the country between 2020 and 2022, and their gills were subjected to parasitological examination. Monogeneans were detected in five host specimens (22.7%) with low mean intensities (6.2± 3.8). They were identified as Cichlidogyrus tilapiae (Monogenea: Dactylogyridae) based on the presence of the following morphometric characteristics: two pairs of anchors, two auricles on the dorsal bar, a V-shaped ventral bar, and an accessory piece with a folded rim and a bent bifurcated tip. The morphological identification was confirmed by the sequence analysis of the specimen’s 18S-ITS1 gene regions and 28S rRNA genes to C. tilapiae from Paratilapia polleni (Cichliformes, Cichlidae) in Madagascar (GenBank accession numbers MH767400 (18S–ITS1) and MH767412 (28S), respectively). This article is the first report on a species of Cichlidogyrus in India, contributing to the growing list of known freshwater monogeneans that are being distributed globally via the ornamental fish trade. Additionally, it adds a new host species (C. socolofi) and geographic location (India) to the existing knowledge of C. tilapiae, a widespread and often co-introduced tropical fish parasite.