Reproductive biology of Echinanthera cyanopleura (Serpentes: Dipsadidae) in southern Brazil

Abstract

ABSTRACT. The reproductive cycles of snakes can be influenced by many factors, both biotic and abiotic, and information about these factors can contribute significantly to knowledge of the biology of many species. Here, we present data on the reproductive biology (body size, sexual dimorphism and female reproductive cycle) of the forest-dwelling colubrid Echinanthera cyanopleura (Cope, 1885), based on analyses of 128 specimens preserved in collections and originating from the states of Paraná, Santa Catarina, and Rio Grande do Sul in southern Brazil. The snout-vent length of females was significantly greater than in males. The tail length of mature females was greater than in males, although this difference was not significant. Vitellogenesis occurs from August to December and eggs were found in greater frequency from October through December. Juveniles were found in larger numbers beginning in February, indicating that recruitment occurs from January to April. The reproductive cycle of this species is seasonal, which is usual for oviparous colubrids of temperate areas of Brazil.

Reproductive biology of the Green Ground Snake Erythrolamprus poecilogyrus sublineatus (Serpentes: Dipsadidae) in Subtropical Brazil

“…This aspect may be related to the lower temperatures of subtropical domains, which may restrict the development of larger clutches even in larger females. The fact that females reach sexual maturity at later stages and larger sizes than males, which was also observed in other dipsadids (Aguiar and Di-Bernardo 2005, Zanella and Cechin 2010, Mesquita et al 2013, Panzera and Maneyro 2013, is related to the high energetic demand for female reproduction and the necessity to reach a sufficient body size to develop a numerically viable clutch (Rivas and Burghardt 2001). The tail in males accommodates the hemipenis and retractor muscles (King 1989) and its higher proportion in this sex seems to be a frequent condition in terrestrial dipsadids (Pizzatto et al 2008b).…”

“…The greater size of females was also observed in other subpecies of E. poecilogyrus (Dixon and Markezich 1992, Giraudo 2001, Pinto and Fernandes 2004 and seems to be a common pattern among oviparous dipsadids (Balestrin and Di-Bernardo 2005, López and Giraudo 2008, Pizzatto et al 2008b, Orofino et al 2010, Zanella and Cechin 2010, Mesquita et al 2013, Panzera and Maneyro 2013. The size of the female body is associated to fecundity in such a way that larger females are able to produce larger clutches (Shine 1994, Panzera and Maneyro 2013).…”

“…Although anuran activity in the area decreases during cold months, most terrestrial and aquatic species can be found throughout the year (Ximenez and Tozetti 2015), which suggests that seasonal variation of food resources may not represent the conditioning factor for the temporal discontinuity in the advanced vitellogenesis of the E. p. sublineatus populations analyzed. The pattern of non-continuous or seasonal female reproduction was found in a variety of guilds and reproductive modes of populations or species from the subtropical Neotropics (Hartmann et al 2004, Aguiar and Di-Bernardo 2005, Balestrin and DiBernardo 2005, Pizzato and Marques 2006, López and Giraudo 2008, Leite et al 2009, Zanella and Cechin 2010, Mesquita et al 2013, Rebelato et al 2016, where temperature seems to represent a strong limiting factor. An examination of the male reproductive cycle based solely on macroscopical analyses is limited to provide an accurate view of the occurring patterns (Rojas et al 2013 (Vieira 1984) and this condition may represent a limiting factor for gametogenesis, in view of its thermal requirements (Girons 1982).…”

Geographical variation in the reproduction and sexual dimorphism of the Boddaert's tropical racer, Mastigodryas boddaerti (Serpentes: Colubridae)

“…The pattern of sexual dimorphism observed in M. boddaerti, in which females are generally larger than males, is typical for many snakes (OROFINO et al 2010, PIZZATTO & MARQUES 2002, PIZZATTO et al 2008, SCARTOZZONI et al 2009, ZANELLA & CECHIN 2010. Sexual dimorphism in which males are larger than females is normally restricted to species in which males compete directly for access to breeding females (SHINE 1993), as within Chironius Fitzinger, 1826, in which the males of most species attain larger sizes than females and are likely to display male-male combat (ALMEIDA- SANTOS & MARQUES 2002, MARQUES et al 2009.…”

“…A larger tail provides the male with additional internal space for the storage of the hemipenis and retractor muscles (KING 1989). An absence of sexual dimorphism in tail size may be related to ecological factors, such as foraging strategies and defense mechanisms (ZANELLA & CECHIN 2010). The fact that 23% of the specimens (of both sexes) from both the Amazon (N = 51) and the Cerrado (N = 23) had broken tails suggests that M. boddaerti may use its tail for defense.…”