Figures 31-36 from: de Freitas ÁJ.B, Bezerra CA.M, Meneses YC, Justo MCN, Viana DC, Cohen SC (2021) Three new species of Urocleidoides (Monogenoidea: Dactylogyridae) parasitizing characiforms (Actinopterygii: Characiformes) in Tocantins River, states of Tocantins and Maranhão, and new record for U. triangulus in Guandu River, state of Rio de Janeiro, Brazil. Zoologia 38: 1-11. https://doi.org/10.3897/zoologia.38.e65001

Figures 31-36 Light photomicrographs of Urocleidoides spp.: (31, 32) Urocleidoides boulengerellae: (31) copulatory complex; (32) vaginal sclerite; (33, 34) Urocleidoides paratriangulus: (33) copulatory complex; (34) haptor; (35, 36) Urocleidoides tocantinensis: (35) copulatory complex; (36) vagina. Scale bars: 31–33, 35–36 = 20 µm, 34 = 40 µm.