Helminth communities of Xiphophorus malinche (Pisces: Poeciliidae), endemic freshwater fish from the Pánuco river, Hidalgo, Mexico

Abstract

A total of 141 highland swordtails, Xiphophorus malinche, were collected from 2 localities in the Pánuco river drainage (Chicayotla and Malila) from Hidalgo, México. The parasite community structure of the 2 localities was examined and compared. Five taxa of helminths were recovered: 2 digeneans, adults of Paracreptotrema sp. and metacercariae of Uvulifer sp.; an adult monogenean, Urocleidoides vaginoclastrum; an adult cestode, Bothriocephalus acheilognathi, and an adult nematode, Rhabdochona xiphophori. Among them, Ur. vaginoclastrum was the most frequent and abundant species. The remaining species were rare and found at low mean abundance. Only 2 species of helminth were found at both localities. The observed species richness, individual abundance, and diversity were low at component community and infracommunity levels. Abundance of helminths and fish standard length were correlated. Uvulifer sp. was more abundant in small fish, but Ur. vaginoclastrum showed the opposite pattern, high abundance in larger fish. Differences observed in this study can be attributed to abiotic and biotic environmental factors resulting from the geographic separation of these localities during to the orogeny of the Sierra Madre Oriental that restricted fish to isolated headwaters.