Oxyascaris caudacutus Freitas, 1958

Aguiar, Aline, Morais, Drausio Honorio, Firmino Silva, Lidiane A., Anjos, Luciano Alves Dos, Foster, Ottilie Carolina & Silva, Reinaldo José Da, 2021, Biodiversity of anuran endoparasites from a transitional area between the Atlantic Forest and Cerrado biomes in Brazil: new records and remarks, Zootaxa 4948 (1), pp. 1-41 : 10-11

Oxyascaris caudacutus Freitas, 1958 ( Baker and Vaucher 1985)

Hosts (prevalence; range): L. chaquensis (3/143; 1–3), L. latrans (1/20; 3) and S. fuscovarius (2/51; 1–3). Site of infection: small intestine.

Stage: adult.

Type host and type locality: Scinax nasicus (Cope) (= Hyla nasica ), Ilha seca, S„o Paulo State, Brazil.

Comments: when Travassos (1920) described the genus Oxyascaris he placed it in the family Oxyascarididae and the superfamily Subuluroidea . Skrjabin et al. (1964) established the superfamily Oxyascaroidea for Oxyascarididae , and after Chabaud (1978) placed Oxyascaris in the family Kathlanidae within the superfamily Cosmocercoidea ( Baker & Vaucher, 1985) . Morphologic structures (in the cephalic region, oesophageal valves and isthmus) observed by Baker & Vaucher (1985) in Oxyascaris spp. resembled species of Cosmocercinae (i.e. Aplectana and Cosmocerca ) resulting in the location of this genus in this subfamily. There are four species of Oxyascaris : Oxyascaris oxyascaris Travassos (= Oxyascaris necopinus , Oxyascaris travassosi ), Oxyascaris similis (Travassos) (= Pteroxyascaris similis ), O. caudacutus (= Pteroxyascaris caudacutus ), and Oxyascaris mcdiasmidi Bursey & Goldberg ( Baker & Vaucher 1985; Bursey & Goldberg 2007). Oxyascaris caudacutus is mainly characterized by prominent lateral alae, wider oesophageal bulb, female tail with much more prominent distal spike, gubernaculum weakly sclerotized, and the following papillae distribution in male tail: four subventral pairs and two subdorsal pairs in postanal region; an unpaired anterior to cloaca lips and three subventral pairs; in preanal region are two rows with 3–4 papillae which are large and near the cloaca. We observed the most of these characters, except the number of papillae arrangement which varied in some specimens, maybe due to their position in the mounting. There are six anuran species reported as hosts of O. caudacutus (see Campi„o et al. 2014; Sena et al. 2018). This is the second report of S. fuscovarius as host for O. caudacutus .