Revista Mexicana de Biodiversidad www.ib.unam.mx/revista/ Revista Mexicana de Biodiversidad 87 (2016) 903-907 Taxonomy and systematics A new species of Characithecium (Monogenea: Dactylogyridae) from external surface and gills of two species of Astyanax (Ostariophysi: Characidae) in southern Brazil Especie nueva de Characithecium (Monogenea: Dactylogyridae) de superficie externa y branquias de dos especies de Astyanax (Ostariophysi: Characidae) en el sur de Brasil

Leopardus colocolo, Leopardus geoffroyi, Leopardus tigrinus and Puma yagouaroundi are wild feline species endangered mainly due to habitat destruction and vehicle run overs. Seventeen felines hit on the roads were collected in Southern Brazil and examined for parasites. Cestodes were identified as Mesocestoides sp. The parasites were found in the small intestine of the hosts with a prevalence of 66.7% (L. colocolo and L. tigrinus), 60% (P. yagouaroundi) and 50% (L. geoffroyi). Rodents and lizards were found in the stomach contents and they possibly were intermediate hosts of Mesocestoides sp. This is the first report of Mesocestoides sp. in wild felines in Brazil.

Toxocara cati (Schrank, 1788) (Nematoda, Ascarididae) em diferentes espécies de felinos silvestres no Brasil: novos registros de hospedeiros. Esta é a primeira descrição detalhada de Toxocara cati parasitando felinos na América do Sul. Dezessete felinos silvestres (Leopardus colocolo, Leopardus geoffroyi, Leopardus tigrinus e Puma yagouaroundi) atropelados foram coletados em diferentes municípios do Estado do Rio Grande do Sul, Brasil. A morfometria de machos e fêmeas permitiu a identificação de espécimes como T. cati. Os helmintos foram encontrados no estômago e intestino dos hospedeiros com prevalência de 66,6% em L. colocolo, L. geoffroyi e L. tigrinus; e 60% em P. yagouaroundi. Foram calculados os parâmetros ecológicos para cada hospedeiro e, L. colocolo teve a maior intensidade de infecção (22,5 helmintos/hospedeiro). Este é o primeiro registro de T. cati parasitando quatro espécies de felinos silvestres no Sul do Brasil e, dois novos registros de hospedeiros para esse parasito.

A new species of Cacatuocotyle is described from the external surface of Astyanax aff. fasciatus and Astyanax jacuhiensis from Lake Guaíba, State of Rio Grande do Sul, Brazil. It differs from the other three species of the genus, recorded from Mexico and the State of Paraná, Brazil, by possessing an accessory piece with a long proximal portion, a U-shaped bar with irregular posterior margin in its midportion, and a haptor containing two circular thickenings with muscular anterior margins. Only one monogenean species, Urocleidoides astyanacis (= Characithecium costaricensis) was recorded for the host Astyanax aff. fasciatus, whereas none were known for A. jacuhiensis. This paper records a new host (A. jacuhiensis) for monogeneans in southern Brazil and extends southward with the geographical distribution of the genus Cacatuocotyle to the State of Rio Grande do Sul, Brazil.

Diplotriaena delirae Pinto & Noronha, 1970 is known to parasitize Pitangus sulphuratus (Linnaeus, 1766) in Peru and in the Midwestern and Southeastern regions of Brazil. Here, specimens of P. sulphuratus were collected in the southern state of Rio Grande do Sul, Brazil, and necropsied. Nematodes (n = 6) found in these specimens were identified as D. delirae based on their morphological traits. This is the first report of D. delirae from southern Brazil, expanding the knowledge of the helminth fauna of P. sulphuratus in the Neotropical region.

Guerrerostrongylus zetta had been found in a number of different species of rodents from northern and southeastern Brazil as well as Argentina. Between 2008 and 2010, specimens of Oligoryzomys nigripes (n = 14) were collected and necropsied. The nematodes encountered were identified as G. zetta due their morphological traits. Prevalence was 78%, with a mean intensity of infection of 5.63 helminths/host. This report fills in a lacuna in the known distribution of G. zetta, and provides the first record of this parasite in the state of Rio Grande do Sul, Brazil.

In Argentina, Saccocoelioides bacilliformis Szidat, 1973 was described from specimens collected probably in Astyanax bimaculatus (Linnaeus, 1758), but latter it was synonymyzed with Saccocoelioides octavus Szidat, 1970. During the examination of digenetic trematodes collected in different species of Astyanax Baird & Girard, 1854 from southern Brazil, we found specimens identified as Saccocoelioides. A detailed comparison of the morphology of the two species revealed that they should be considered valid, thus this study proposes the revalidation of S. bacilliformis. The traits that allowed the revalidation were: body shape, position of the caecal bifurcation, and the extension of the uterus and vitellarium. Parameters of infections are provided for the first time in addition to records of new hosts and new locality.

Para a Região Neotropical, a única espécie de Cylicospirura registrada para felídeos silvestres foi Cylicospirura (Cylicospirura) subaequalis no Paraguai e Brasil. Durante 2007 e 2009, espécimes atropelados de Leopardus geoffroyi (n = 6) foram doados para necropsia. Nematoides encontrados no estômago foram identificados como Cylicospirura (Cylicospirura) felineus pela presença de seis dentes trífidos, vulva anterior à junção do esôfago com intestino e, tamanho dos espículos. A prevalência de C. (C.) felineus em L. geoffroyi foi 16,7%. Não foram observadas lesões causadas pelos nematoides no hospedeiro infectado, como registrado em outros estudos. Este é o primeiro registro de C. (C.) felineus para a Região Neotropical (Estado do Rio Grande do Sul, Brasil) e, L. geoffroyi como novo hospedeiro.