Integrative taxonomy ofUrocleidoidesspp. (Monogenoidea: Dactylogyridae) parasites of characiform and gymnotiform fishes from the coastal drainages of the Eastern Amazon, Brazil

Abstract

AbstractEight species (four new) ofUrocleidoidesare reported from Characiformes and Gymnotiformes fishes of the coastal drainages of the Eastern Amazon.Urocleidoides vaninin. sp. is characterized by having a male copulatory organ (MCO) with three and a half counterclockwise rings, absence of vaginal sclerite, and a V-shaped ventral bar.Urocleidoides atilaiamarinoin. sp. has MCO with two and a half counterclockwise rings, dumbbell-shaped accessory piece, similar anchors, open V-shaped ventral bar, and open U-shaped dorsal bar.Urocleidoides macrosoman. sp. exhibits an elongate and robust body, MCO comprising one counterclockwise ring, similar anchors with wavy point, and dumbbell-shaped ventral and dorsal bars.Urocleidoides nataliapasternakaen. sp. has MCO comprising two and a half counterclockwise rings, vaginal canal convoluted, point of the dorsal anchor with ornamentation as sclerotized shredded filaments, elongate dumbbell-shaped ventral bar, and U-shaped dorsal bar.Urocleidoides narisandUrocleidoides brasiliensisfromH. malabaricus(Characiformes) and theincertae sedisspecies,Urocleidoides gymnotusandUrocleidoides carapus, fromSternopygus macrurus(Gymnotiformes) are reported, and their molecular sequences are presented in this study. Phylogenetic analyses based on molecular data (28S rDNA and COI mtDNA) reveal that species ofUrocleidoideslacking vaginal sclerite are closely related to species that possess vaginal sclerite, suggesting that the absence of vaginal sclerite inUrocleidoidesmay be the result of a secondary loss. The relationships between species ofUrocleidoidesand other Neotropical dactylogyrids are also addressed.