![##common.pageHeaderLogo.altText##](https://revistas.up.ac.pa/public/journals/3/pageHeaderLogoImage_es_ES.png)
Between 1994 and 2006 samplings were made in different rivers of the Provinces of Veraguas, Chiriqui, Herrera and Cocle with the objective to raise information of the continental fish of the region, as well as to determine the species of crustaceans and mollusks in some of the localities. The samplings were made in Veraguas: Eastern zone of the peninsula of Sona, western zone of the peninsula of Azuero, Cobre river, Santa Maria river, Calovebora river and some creeks of Santiago. In Chiriqui in the river basins of the rivers: Chiriquí Viejo, Chico, Chiriquí, Fonseca, San Felix and Tabasara; and in Herrera: the Parita and La Villa rivers. 93 species of fish were identified, 10 species of crustaceans and six families of moluscos. The index of similarity calculated indicates that the ictiofauna of Darien presents greater similarity with the one of Santa Maria in comparison with the ictiofauna of the rivers that borders the Golfo de Montijo and Chiriquí. In our rivers and creeks inquires into the presence of two introduced species: Poecilia reticulata (Poeciliidae) and Cichlasoma dovii (Cichlidae).