Helminth parasites of fishes from the hydroelectric power station of Eletrosul (Brazil). 1 - Procamallanus petterae n. sp. and Spirocamallanus pintoi n. sp. (Nematoda, Camallanidae) from the reservoir of 'Salto Osorio'. Memorias do Instituto Oswaldo Cruz, 83(3) 1988: 293-298. 293 [Zoological Record Volume 125]