A New Species of Cosmocercoides (Ascaridida: Cosmocercidae) Parasitic in Tree Frogs from Southern Amazonia.

Cosmocercoides meridionalis n. sp. is described from the large and small intestines of 5 species of tree frogs belonging to the families Hylidae and Phyllomedusidae collected from 2 localities in Southern Amazonia. The new species is allocated to the genus Cosmocercoides Wilkie, 1930, due to the presence of papillae in rosettes, which are complex caudal papillae surrounded by punctuations. Cosmocercoides meridionalis n. sp. differs from its congeners by a combination of the following characters: the absence of the gubernaculum, the total length of the female (twice the size of the male), and the presence of 26 rosette papillae with a unique arrangement and distribution pattern: 11 pre-cloacal pairs, 1 ad-cloacal pair, and 1 post-cloacal pair. This is the first species of the genus described from the Amazonia region.

A new species of Metadelphis Travassos, 1944 (Digenea: Dicrocoeliidae) from the gall-bladder of Molossus molossus (Pallas) (Chiroptera: Molossidae) in the Brazilian eastern Amazon.

Metadelphis tkachi n. sp. is described based on material from the gall-bladder of Molossus molossus (Pallas) (Chiroptera: Molossidae) in the Brazilian eastern Amazon. The main differentiating characters of the new species include lobed, tandem testes and elongated clusters of vitelline follicles commencing at the level of the seminal receptacle. The new species can be distinguished from Metadelphis lenti (Santos & Gibson, 1998) and Metadelphis apharyngotrema (Marshall & Miller, 1979) by the shape and position of the testes; from Metadelphis evandroi Travassos, 1944 by having tandem, lobed testes and shorter clusters of vitelline follicles; from Metadelphis compactus Travassos, 1955 by having tandem testes and more elongated clusters of vitelline follicles, and from Metadelphis alverangai Travassos, 1955 by having smaller testes and body, and vitellarium with large follicles. New morphological data are reported for M. lenti based on light and scanning electron microscopy; intraspecific variation was observed.

Neocosmocercella fisherae n. sp. (Nematoda: Cosmocercidae), a parasite of the large intestine of Phyllomedusa bicolor (Boddaert) (Anura: Phyllomedusidae) from the Brazilian Amazon.

Neocosmocercella fisherae n. sp. is the first nematode species found parasitising Phyllomedusa bicolor from the Brazilian Amazon Region. The new species has a triangular oral opening, with bi-lobed lips, and is distinguished from N. bakeri (triangular oral opening with simple lips), and from N. paraguayensis (hexagonal oral opening with bi-lobed lips). Additionally, the new species has ciliated cephalic papillae, which are absent in the other species of the genus. The reduced uterine sac and the presence of a single egg in the uterus in females are the main morphological characters that differentiate the new species from its congeners N. bakeri (8-10 eggs) and N. paraguayensis (10 eggs, based on the allotype). Additionally, the new species differs from the other two species of the genus by morphometric characters such as the size of spicules and gubernaculum in males and the vagina in females. Until now, phyllomedusid anurans are the only known hosts for the nematodes of this genus. The present work describes the third species of the genus and the first species of nematode parasitising P. bicolor.

A new species of Neocosmocercella Baker & Vaucher, 1983 (Nematoda: Cosmocercidae), a parasite of Phyllomedusa vaillantii Boulenger (Anura: Phyllomedusidae) in the Caxiuanã National Forest, eastern Amazon, Brazil.

Neocosmocercella bakeri n. sp. is described from the large intestine of Phyllomedusa vaillantii Boulenger collected in the Caxiuanã National Forest in the Eastern Brazilian Amazon. The new species is easily distinguished from the type-species of the genus, Neocosmocercella paraguayensis Baker & Vaucher, 1983 in possessing a triangular mouth opening with three simple lips (vs three bi-lobed lips and hexagonal mouth opening) and somatic papillae, which are absent in N. paraguayensis. The males of the new species are distinguished by the distribution of the sessile cloacal papillae and the dimensions of the gubernaculum, whereas the females are distinguished by their smaller size and opisthodelphic uterus. This study expands the diagnostic characters of Neocosmocercella Baker & Vaucher, 1983, reports the first species parasitising anurans of the Brazilian Amazon, a new host record for the genus, and the description of the second species of the genus.