V. sanguinea are obligatorily hematophagous, preying solely on the blood of their hosts. Attracted by the scent of urea, the parasites proceed to attack the dorsal or ventral arteries of the gills by wedging themselves under the gill flaps of hosts, erecting their dorsal and opercular spines to secure their position, accessing the blood supply via dagger-like teeth, and engorging themselves on the meal before disengaging their hosts (Baskin et al., 1980). They are capable of obtaining a full meal of blood anywhere from 30 to 145seconds (Zuanon and Sazima, 2005). Small scratches within the gill filaments of hosts indicate that V. cirrhosa bite the medial and proximal area of the gill filaments and simply allow the pressurized arterial blood to flow into their alimentary canals (Zuanon and Sazima, 2003). Incidents of a related species, V. cirrhosa, swimming up human urethras have been reported as these fish mistake the chemicals released in urine as natural waste products of prey items (Fernandez and Schaeffer, 2009).
Candiru Feeding on Goldfish: Feeding involves obtaining access to the branchial arteries of the host through the opercular openings
