A diplectanid monogenean, Acleotrema lamothei n. sp., is described from the gills of the yellow sea chub Kyphosus incisor (Cuvier, 1831) in Brazilian waters off Rio de Janeiro State. This species is distinguished by the facts that the male copulatory organ is armed with spines throughout most of its length, the ventral hamuli have a very long, stout outer root, which is slightly notched proximally, an inner root less than half the length of the outer root and a fine blade and point. It also differs from most species of the genus by the greater size of the haptor and its hard parts. This is the first record of a species of Acleotrema Johnston and Tiegs, 1922 from South American waters.

Se describe Acleotrema lamothei n. sp. de las branquias del pez Kyphosus incisor (Cuvier, 1831) recolectado en las costas del estado de Río de Janeiro, Brasil. La nueva especie se distingue por la armadura del órgano copulador con espinas en casi toda su longitud, por la presencia de una raíz externa larga y robusta en el hámuli ventral, provista de una pequeña muesca proximal, por la raíz interna que mide menos de la mitad de la longitud de la externa y por tener la hoja y la punta finas. Asimismo, difiere de muchas de las especies del género por el gran tamaño del haptor y de sus partes esclerozadas. El presente constituye el primer registro de una especie de Acleotrema Johnston y Tiegs, 1922 en aguas sudamericanas.

Cestóides hiperparasitos são descritos de espécies de proteocefalídeos, que ocorrem em peixes pimelodídeos de diferentes regiões do Brasil. Referimos ainda, a ocorrência de nematóide hiperparasito em espécimes de Choanoscolex abscissus, do peixe pimelodídeo, Pseudoplatystoma carruscans. São citadas as referências anteriores de cestóides e nematóides hiperparasitos, e discutida a possível identificação dos mesmos.

Proteocephalid cestode hyperparasite are reported from numerous proteocephalids occurring in pimelodid fishes in different regions of Brazil. In addition, three specimens of a nematode hyperparasite are reported from the proteocephalid cestode Choanoscolex abscissus from the pimelodid fish Pseudoplatystoma corruscans in Brazil. Previous records of cestode and nematode hyperparasite of cestode are listed, and the possible identities of the Brazilian records are discussed.