Diet, sexual dimorphism and reproduction of sympatric racers Philodryas aestiva and Philodryas patagoniensis from the coastal Brazilian Pampa

Abstract

How to cite: QUINTelA FM AND lOeBMANN D. 2019. Diet, sexual dimorphism and reproduction of sympatric racers Philodryas aestiva and Philodryas patagoniensis from the coastal Brazilian Pampa. An Acad Bras Cienc 91:Abstract: Herein we investigated diet, sexual dimorphism and reproductive biology of two sympatric congeneric species at the coastal Brazilian Pampa, Philodryas aestiva and P. patagoniensis. Analysis of the stomach content of the scansorial Philodryas aestiva revealed that it feeds mainly on Anura and small mammals, while it occasionally consumes Insecta, Squamata and Aves. The more terrestrial Philodryas patagoniensis presented a broader diet, composed mainly of Anura, Squamata and small mammals. Insecta and Actinopterygii were found in lower frequencies. In females of both species, snout-vent length was significantly larger than in males, while tail length/snout-vent length ratio was significantly higher in males. Males reach sexual maturity at smaller sizes than females in both species. Fecundity was higher in P. patagoniensis (3 to 24 eggs; 15 ± 8.15) than in P. aestiva (10 to 20 eggs; X = 14.50 ± 3.53). Females of P. aestiva showed secondary follicles in all seasons while eggs occurred from middle-winter to early-summer. Secondary follicles occurred throughout the year in P. patagoniensis, but concentrated in spring. eggs occurred in late-summer, middle-autumn and spring. Both species presented positive correlations between SVL and clutch size. Differences in analyzed traits seem to reflect divergences in species morphology and use of habitat/microhabitat.

Lista comentada de las serpientes de la Argentina, con referencias a su sistemática, distribución geográfica, dieta, reproducción, potencial peligrosidad y etimologías

“…Alimentación: Anfibios anuros, lagartijas, aves, roedores, murciélagos y otros ofidios (Leynaud & Bucher, 1999;Carreira et al, 2005;Quintela & Loebmann, 2019). Especialista en anuros según Bellini et al (2015).…”

“…Alimentación: Dieta sumamente variada, ya que se alimenta de saurios, pichones de aves, anfibios, roedores, marsupiales, insectos, y puede ser ofiófaga e incluso caníbal (Cei, 1993;Gonzaga et al, 1997;Di-Bernardo 1998;Cechin, 1999;Hartmann, 2001;Vidal, 2002;Hartmann & Marques 2005;Bellini et al, 2015;Quintela & Loebmann, 2019). Gallardo (1989) y posiblemente Serié (1919) indican que se alimenta de crías de liebre europea.…”

The Venom Composition of the Snake Tribe Philodryadini: ‘Omic’ Techniques Reveal Intergeneric Variability among South American Racers

“…Regarding their feeding ecology, several studies have indicated that most species of Philodryadini have generalist diets, feeding on invertebrates, small rodents, lizards, amphibians, birds [9][10][11][12][13][14][15][16][17][18][19][20], bats [21,22] and other snakes [19,23]. On the other hand, some species, such as P. agassizii, differ by having a very specialized diet.…”