Herpetology Notes, volume 12: 975-980 (2019) (published online on 10 October 2019) First record of Rhabdias cf. breviensis (Rhabditoidea: Rhabdiasidae) parasitizing Scinax acuminatus (Anura: Hylidae) in the Southern Pantanal wetland, Brazil Isabela Caroline Oliveira da Silva1,*, Priscilla Soares1,2, Maiara Cabrera Miguel1,2, Rodney Murillo Peixoto Couto2, Giovana Martins Miranda1, André Mota Alves3, and Fernando Paiva1 Parasitic nematodes of the genus Rhabdias Stiles There are also some taxa only at generic level, or needing et Hassall, 1905 are lungworms commonly found in more information to confirm the specific identification: amphibians and some reptiles (Kuzmin et al., 2016). Rhabdias sp., Rhabdias aff. sphaerocephala, Rhabdias These helminths have a complex life cycle that cf. breviensis, and Rhabdias [cf. elegans] (Kloss 1971; alternates from a free-living generation on the soil to Sueldo and Ramirez, 1976; Baker, 1987; Vicente et al., another that is a parasite in the lung of amphibians and 1991; González and Hamann, 2007; Santos et al., 2011; reptiles (Baker, 1979; Langford and Janovy, 2009). In Hamann et al., 2013; Nascimento et al., 2013; Draghi South America, 12 species of Rhabdias were reported et al., 2015; Kuzmin et al., 2016; Teles et al., 2018a; parasitizing amphibians: R. androgyna Kloss, 1971; Oliveira et al., 2019). Those taxa are distributed in R. breviensis Nascimento et al., 2013; R. elegans Argentina, Guyana, Paraguay, Peru, Uruguay, and Brazil Gutiérrez, 1945; R. fuelleborni Travassos, 1926; R. (González and Hamann, 2007; McAllister et al., 2010; galactonoti Kuzmin et al., 2016; R. hermafrodita Kloss, Toledo et al., 2017). In the latter country, those species 1971; R. mucronata Schuurmans-Stekhoven, 1952; R. were reported to occur in the states of Amazonas, Bahia, paraensis Santos et al., 2011; R. pseudosphaerocephala Ceará, Distrito Federal, Espírito Santo, Mato Grosso do Kuzmin et al., 2007; R. sphaerocephala Goodey, 1924; Sul, Minas Gerais, Pará, Paraná, Pernambuco, Piauí, R. stenocephala Kuzmin et al., 2016; and R. truncata Rio de Janeiro, Rio Grande do Sul, and São Paulo Schuurmans-Stekhoven, 1952. However, R. mucronata (Kloss, 1971; Vicente et al., 1991; Souza et al., 2016; and R. truncata are species inquirendae that are poorly Müller et al., 2018). described and difficult to recognize, especially since The Mato Grosso snouted treefrog, Scinax acuminatus only female and young individuals are known (Barrella (Cope, 1862) (Figure 1), is a medium-sized, arboreal et al., 2010). 1 Laboratório de Parasitologia Animal, Instituto de Biociências, Universidade Federal de Mato Grosso do Sul, Avenida Costa e Silva s/n, Campo Grande, Mato Grosso do Sul 79070-900, Brazil. 2 Laboratório de Pesquisa em Herpetologia, Instituto de Biociências, Universidade Federal de Mato Grosso do Sul, Avenida Costa e Silva s/n, Campo Grande, Mato Grosso do Sul 79070-900, Brazil. 3 Laboratório de Biologia Tropical, Instituto de Tecnologia e Pesquisa, Universidade Tiradentes, Avenida Murilo Dantas, 300, Farolândia, Aracaju, Sergipe 49032-490, Brazil. Figure 1. Specimen of Scinax acuminatus. Photo by Rodney * Corresponding author. E-mail: [email protected] Murillo Peixoto Couto. 976 Isabela Caroline Oliveira da Silva et al. and nocturnal hylid distributed in Argentina, Bolivia, surrounded by two lateral lips and four submedian lips. Paraguay and in Brazil on the West and Midwest Morphological dimensions are provided in Table 2. regions (Frost, 2019). It is found in open areas where Although these characteristics confirm the similarity males vocalize perched on shrubs and branches at the with R. breviensis, we decided to identify as Rhabdias edge of permanent and semi-permanent ponds (Prado et cf. breviensis, due to the genus Rhabdias present al., 2005; Prado and Haddad, 2005). Previous records of species with very similar morphological characteristics, parasites in this host show occurrences of acanthocephala mainly when it comes to female individuals as found Acanthocephalus caspanensis Fernandez and Ibarra, (Martínez-Salazar et al., 2009). Further research using 1989 and nematodes such as Aplectana sp. Railliet more specimens of this parasite are needed for specific and Henry, 1916; Cosmocerca parva Travassos, 1925; confirmation. Oxyascaris caudacutus (Freitas, 1958) Baker and Vaucher, 1984; Physaloptera Rudolphi, 1819; and Rhabdochonidae Skrjabin, 1946, in Argentina, Brazil and Paraguay (Vicente et al., 1991; Smales, 2007; González and Hamann, 2008, 2010). In this context the aim of this study was present the first record of Rhabdias cf. breviensis parasitizing S. acuminatus in southern Pantanal wetland, Mato Grosso do Sul State, Brazil. In December 2014, 15 specimens of S. acuminatus were collected in temporary and permanent ponds at the “Fazenda Nhumirim” (Nhecolândia sub-region), Municipality of Corumbá, Mato Grosso do Sul State, Brazil (-18.988054°, -56.619056°, datum: WGS84). Collected specimens were transported alive to the laboratory, and euthanasia was performed with the topical use of Xylocaine® ointment 5% (CONCEA, 2013). Subsequently, the body cavities and internal organs were examined for parasites. The parasite was found in the host lung, and after its removal prepared on a temporary slide with glycerine clarification for a morphological identification. Morphological and morphometric characters were taken under a light microscope LEICA model DM5500™, equipped with computerized system for capturing and processing images (LAS 3.9™ LEICA). The measures for morphological identification were performed in micrometres. The examined anuran specimen was fixed in formalin 10%, and preserved in alcohol 70o GL. Anuran and parasite specimen were housed at the Zoology Reference Collection of the Universidade Federal de Mato Grosso do Sul (Scinax acuminatus: ZUFMS-AMP12432, Rhabdias cf. breviensis: ZUFMS- NEM00074). The identified parasite is an adult hermaphrodite female that differs morphologically from other Rhabdias species due to reduced body size, along with the characteristics Figure 2. Rhabdias cf. breviensis recovered in an adult male of cuticular swelling covering the body extending, from Scinax acuminatus. (A). Light microscopy image, side view the buccal opening to the posterior end of the tail (Fig. of the body. (B). Schematic drawing; a = total body view; b = 2); two pairs of submedian cephalic papillae and the one extremity anterior of the body; c = extremity posterior of the pair of lateral cephalic papillae. It also has oral aperture body. Photo by Priscilla Soares. First record of Rhabdias cf. breviensis parasitizing Scinax acuminatus, Brazil 977 Table 1. Records of species of Rhabdias in South American anurans published between 2015 and 2019. Abbreviations for all countriesTable 1. citedRecords are of species in parentheses: of Rhabdias in ArgentinaSouth American (ARG); anurans published Brazil between(BRA); 2015 Peru and 2019.(PER). Abbreviations for all countries cited are in parentheses: Argentina (ARG); Brazil (BRA); Peru (PER). Host (family/species) Species of Rhabdias Locality (Country) Reference Bufonidae Rhinella diptycha (Cope, 1862) Rhabdias breviensis Municipality of Castilho, São Paulo State (BRA) Müller et al. (2018) Rhabdias pseudosphaerocephala Municipality of Castilho, São Paulo State (BRA) Müller et al. (2018) Municipality of Porto Rico, Paraná State (BRA) Müller et al. (2018) Rhabdias sp. Municipality of Botucatu, São Paulo State (BRA) Müller et al. (2018) Rhinella granulosa (Spix, 1824) Rhabdias androgyna Municipality of Aiuaba, Ceará State (BRA) Teles et al. (2018a) Rhabdias breviensis Municipality of Picus, Piauí State (BRA) Müller et al. (2018) Rhinella icterica (Spix, 1824) Rhabdias fuelleborni Municipality of Botucatu, São Paulo State (BRA) Moretti et al. (2017) Rhinella jimi (Stevaux, 2002) Rhabdias pseudosphaerocephala Municipalities of Santana do Cariri and Farias Müller et al. (2018) Brito, Ceará State (BRA) Municipality of Picus, Piauí State (BRA) Müller et al. (2018) Rhinella major (Müller and Hellmich, 1936) Rhabdias elegans Chaco Province (ARG) Hamann and González (2017) Rhabdias pseudosphaerocephala Chaco Province (ARG) Hamann and González (2017) Rhinella marina (Linnaeus, 1758) Municipality of Manaus, Amazonas State (BRA) Müller et al. (2018) Municipality of Tarapoto, San Martín Department Toledo et al. (2017) (PER) Dendrobatidae Adelphobates galactonotus (Steindachner, 1864) Rhabdias galactonoti Municipality of Melgaço, Pará State (BRA) Kuzmin et al. (2016) Hylidae Boana raniceps (Cope, 1862) Rhabdias pseudosphaerocephala Municipality of Porto Rico, Paraná State (BRA) Müller et al. (2018) Rhabdias sp. Municipality of Selvíria, Mato Grosso do Sul State Souza et al. (2016) (BRA) Scinax fuscovarius (Lutz, 1925) Rhabdias breviensis Municipality of Castilho, São Paulo State (BRA) Müller et al. (2018) Rhabdias sp. Municipality of Diamante do Norte, Paraná State da Graça et al. (2017) (BRA) Leptodactylidae Leptodactylus fuscus (Schneider, 1799) Rhabdias breviensis Municipality of Castilho,Barro, Ceará São StatePaulo (BRA) State (BRA) Müller et al. (2018) Leptodactylus macrosternum (Miranda-Ribeiro, Rhabdias cf. stenocephala Municipalities of Barro and Farias Brito, Ceará Müller et al. (2018) 1926) State (BRA) Rhabdias sp. Municipality of Aiuaba, Ceará State (BRA) Teles et al. (2018b) Leptodactylus pentadactylus (Laurenti, 1768) Rhabdias stenocephala Municipality of Melgaço, Pará State (BRA) Kuzmin et al. (2016) Rhabdias sp. Municipality of Corrientes, Corrientes Province