Cosmocerca sp. (Nematoda: Cosmocercidae) large intestine parasite of Pithecopus nordestinus (Anura: Phyllomedusidae) of an Ecotone from Caatinga

DE OLIVEIRA RODRIGUES, ALLAN RODRIGO; GONZÁLEZ, CYNTHYA E.; LOPES LEITE, BN; PENHA FURTADO, A; DOS SANTOS, ANA NUNES; DE VASCONCELOS MELO, FRANCISCO TIAGO; FREIRE, SM; NASCIMENTO DOS SANTOS, J

Rio de Janeiro

Congreso; XXV Congreso Brasilero de Parasitología; 2017

Sociedad Brasilera de Parasitología

Nematodes of Cosmocercidae family are commonly found parasitizing anurans, mainly because they have a direct life cycle and/or cutaneous infection. Cosmocerca Diesing, 1861,  is a nematode genus composed of species that are characterized mainly by males presenting papillae with plectanes and rosette in the ventral region of the tail and females presented uterus with few eggs. Pithecopus nordestinus (Caramaschi 2006), is distributed in northeastern region Brazil, in the caatinga and adjacent regions, in the states of Piauí, Ceará, Rio Grande do Norte, Paraíba, Pernambuco, Alagoas, Sergipe, Bahia and Minas Gerais, this can be distinguished from Similar species by a combination of color patterns and morphological characteristics. Although studies on amphibian parasite nematodes have grown in recent years, there is still a gap on the biodiversity of these parasites. So far, there are no records helminth parasites reported for P. nordestinus and the aim of this work is to describe nematodes of the genus Cosmocerca found parasitizing the large of intestine P. nordestinus from Caatinga Biome. During an expedition to collect helminths of amphibians and reptiles, fourteen individuals of P. nordestinus, collected in Barras, Piauí state, were anesthetized, necropsied and the nematodes found were rinsed in saline solution and fixed with heated 70% alcohol. For morphological characterization, the nematodes were clarified in Aman?s Lactophenol and analyzed in an Olympus BX53 microscope coupled with image capture system. The nematodes found have evident sexual dimorphism, somatic papillae present, anterior region with three lips, oxyuroid type esophagus. Nerve ring located in the median region of the esophagus, excretory pore near the bulb and the tail is short and sharp. The males have two spicules, gubernaculum is present, five pairs of papillae in rosettes with plectanas, pre-cloacal, situated in the ventral region of the tail uniformly spaced apart from each other. Females have few eggs and a vulva lying in the median region of the body. Among the species of Cosmocerca that occur in the Neotropical region, the species of the present study resembled by the number of pairs of papillae supported by plectanes to three species, also found parasitizing anurans: C. podicipinus and C. travassosi that have five pairs of plectanes each and C. parva that have five to seven pairs of plectanes. However, they differ in other morphological characteristics such as gubernaculum, spicule size and shape, tail characteristics and structure and distribution of plectanes. Thus, the nematodes of the present study may belong to a new species, and further morphological, morphometrical and molecular studies are required for the identification of the species.