Morphological and molecular characterization of Cosmocercoides amapari n. sp. (Nematoda: Cosmocercidae), parasitic in hylid frogs from the Brazilian Amazon.

Cosmocercoides Wilkie, 1930 are gastrointestinal parasites commonly found in amphibians and reptiles, with 4 species reported from the Neotropical region. In the present study, a new species of Cosmocercoides, namely Cosmocercoides amapari n. sp. is described using integrated approaches such as light and scanning microscopy, and DNA sequencing of the mitochondrial cytochrome c oxidase subunit 1 gene. The specimens were collected from the large intestine of 3 species of hylid frogs in Amapá, Brazil. The new species can be distinguished from its congeners by morphological traits, including the pattern of caudal papillae, absence of the gubernaculum, 2 poorly sclerotized spicules, presence of lateral alae and somatic papillae along the body. In addition, our molecular analyses and phylogenetic reconstructions strongly support the status of the new taxon, which clustered poorly with a large clade of Cosmocerca spp. Cosmocercoides amapari n. sp. is the 29th species of the genus, the 5th from the Neotropical region, the third reported in Brazil, the second described from the Amazon region and the first belonging to the Neotropical region with molecular data.

Ophiotaenia karipuna n. sp. (Eucestoda: Proteocephalidae), a parasite of Erythrolamprus miliaris (Linnaeus, 1758), with redescription of Ophiotaenia arandasi (Santos and Rolas, 1973) from the Brazilian Amazon.

Ophiotaenia is the most diverse genus among proteocephalids, composed of species commonly found parasitizing snakes worldwide. However, the diversity of Ophiotaenia in the Neotropical region is still underestimated. This study describes Ophiotaenia karipuna n. sp. found parasitizing Erythrolamprus miliaris in the State of Amapá, Brazil. Additionally, we redescribe Ophiotaenia arandasi based on a re-examination of type series and newly collected material from Erythrolamprus taeniogaster in the State of Pará, Brazil. The new species differs from its congeners in the following characteristics: scolex width, number of testes, relative length of the cirrus-sac, absence of a vaginal sphincter, presence of a vestigial apical organ resembling a sucker, and relative size of the ovary in relation to the surface of the proglottid. Furthermore, we provide taxonomic information for Ophiotaenia arandasi not reported in the original description, including morphology of embryophore, uterine development, and the absence of the vaginal sphincter in the species. Ophiotaenia karipuna n. sp. represents the 21st- species described in snakes -from the Neotropical region and the first formally described in the Brazilian Amazon. Additionally, we provide the first ultrastructural analysis, a new host, and locality records for O. arandasi.

The tadpole of Amazophrynella teko (Anura: Bufonidae) from the eastern Amazon, Brazil.

The genus Amazophrynella Fouquet, Recoder, Teixeira, Cassimiro, Amaro, Camacho, Damasceno, Carnaval, Moritz, and Rodrigues, is represented by 12 nominal species and distributed in the Amazon region of Brazil, Bolivia, Colombia, Ecuador, Guyana, French Guiana, Peru, and Venezuela (Frost 2020). In the last eight years, ten species from this genus have been described. However, despite the wide distribution and diversity of these species, only the tadpole of Amazophrynella manaos Rojas, Carvalho, Ávila, Farias, and Hrbek from the Brazilian Amazon (Menin et al. 2014) and A. siona Rojas, Fouquet, Ron, Hernández-Ruz, Melo-Sampaio, Chaparro, Vogt, Carvalho, Pinheiro, Ávila, Farias, Gordo, and Hrbek from Ecuador have been formally described (Duellman Lynch 1969; Rojas et al. 2018). Literature about tadpole morphology, reproduction, and bioacoustics of Amazophrynella is scarce and necessary to a comprehensive taxonomic classification (Kaefer et al. 2019). Herein, we describe the tadpole of the recently described species Amazophrynella teko Rojas, Fouquet, Ron, Hernández-Ruz, Melo-Sampaio, Chaparro, Vogt, Carvalho, Pinheiro, Ávila, Farias, Gordo, and Hrbek, found in the northeastern Amazon, in the State of Amapá, Brazil, and in French Guiana.

The tadpole of Elachistocleis helianneae Caramaschi, 2010 (Anura: Microhylidae).

The neotropical genus Elachistocleis Parker comprises 18 described species [including Elachistocleis ovalis (Schneider) which is considered a nomen dubium by Caramaschi (2010), with pending revision]. This genus is distributed in Central America and most of South America, from Panama and Trinidad to southern Paraguay, including central Argentina, Uruguay, Venezuela, Colombia, Bolivia, Guyana, Surinam, French Guiana, and Brazil (Marinho et al. 2018; Frost 2019). Currently, the tadpoles of ten species have been described and/or figured: Elachistocleis bicolor (Guérin-Méneville), E. cesarii (Miranda-Ribeiro), E. erythrogaster Kwet and Di-Bernardo, E. haroi Pereyra, Akmentins, Laufer and Vaira, E. muiraquitan Nunes-de-Almeida and Toledo, E. ovalis, E. panamensis (Dunn, Trapido and Evans), E. pearsei (Ruthven), E. surinamensis (Daudin), and Elachistocleis sp. (Kenny 1969; Williams & Gudynas 1987; Kwet & Di-Bernardo 1998; Duellman 2005; Lynch 2006; Rossa-Feres & Nomura 2006; Vera Candioti 2006; Magalhães et al. 2012; Pereyra et al. 2013).