Oxyrhopus guibei Hoge & Romano, 1977

De Alencar, Arília Aiarsa Laura R. V. & Martins, Marcio, 2013, Natural History Of Pseudoboine Snakes, Papéis Avulsos de Zoologia 53 (19), pp. 261-283 : 267-268

Oxyrhopus guibei Hoge & Romano, 1977

Distribution: Oxyrhopus guibei is widely distributed in central, eastern, and southern Brazil, northeastern Argentina, eastern Bolivia, and southern Paraguay ( Sazima & Abe, 1991; Sazima & Haddad, 1992; Yanosky et al., 1996; Zaher, 1996; Xavier-Freire, 1999; Giraudo & Scrocchi, 2002; Argôlo, 2004; Tozetti et al., 2004; Santana et al., 2008).

Habitat and time of activity: Oxyrhopus guibei is a moderate-sized pseudoboine (Maximum SVL = 1080 mm, female; Pizzatto & Marques, 2002). The extensive amount of habitat use data indicates that this species inhabits both forested and open areas, and is frequently found in disturbed areas ( Sazima & Haddad, 1992; Xavier-Freire, 1999; Argôlo, 2004; Sawaya et al., 2008; Araújo et al., 2010). Data on microhabitat use indicates that O. guibei is a terrestrial species (N = 11; Sazima & Abe, 1991; Sazima & Haddad, 1992; Santana et al., 2008; F.E. Barbo, unpublished data; C. Strüssmann, unpublished data), although Sawaya et al. (2008) have found one individual moving 30 cm above the ground. It is active both during the day (N = 31; Sazima & Haddad, 1992; Pereira-Filho, 2007; Sawaya et al., 2008; F.E. Barbo, unpublished data) and night (N = 30; Sazima & Abe, 1991; Sawaya et al., 2008; Araújo et al., 2010; Barbo et al., 2011; F.E. Barbo, unpublished data).

Feeding: Andrade & Silvano (1996) suggested that O. guibei presents an ontogenetic shift in diet, and our results show that it feeds heavily on mammals (N = 66; two Bolomys lasiurus , one Calomys laucha , one Mus musculus , one Rattus sp. , rodents), but also eat lizards (N = 18, three Ophioides sp. , six Hemydactylus mabouia ), and occasionally birds (N = 1; Leptotila sp. ) ( Andrade & Silvano, 1996; Sazima & Abe, 1991; Dalmolin, 2000; Barbo et al., 2011).

Reproduction: Clutch size varies from three to 20 eggs (N = 105, mean = 12.3 eggs; Pizzatto & Marques, 2002; Sawaya et al., 2008; Barbo et al., 2011; Braz & Manço, 2011; F.E. Barbo, unpublished data) and this species presents a continuous reproductive cycle ( Pizzatto & Marques, 2002). The smallest mature female was 612 mm SVL (F.E. Barbo, unpublished data) and the smallest mature male was 388 mm SVL (F.E. Barbo, unpublished data). Pizzatto & Marques (2002) found a significant sexual size dimorphism, females being larger than males.

Defense: When handled O. guibei can struggle and discharge cloacal secretions ( Pereira-Filho, 2007; Sawaya et al., 2008).