Biologia reprodutiva de Cercosaura schreibersii (Squamata, Gymnophthalmidae) e Cnemidophorus lacertoides (Squamata, Teiidae) no escudo Sul-Riograndense, Brasil

Abstract

Abstract:Gonads of 124 specimens of Cercosaura schreibersii (Wiegmann, 1834) and 192 specimens of Cnemidophorus lacertoides Duméril & Bibron, 1839 from the Sul-Riograndense Shield, Rio Grande do Sul, Brazil were analyzed. Both species presented seasonal reproduction, with vitellogenic females found at the end of winter and spring, gravid females in spring and summer and recruitment recorded during the months with the higher mean temperatures in the region. Variation of testis volume was not observed in males of C. schreibersii throughout the year, while adult males of C. lacertoides had variation, with larger testis found in spring. All clutches of C. schreibersii comprised two eggs and data suggest positive correlation between female SVL and egg size (R 2 = 0.55; p < 0.05). Clutch size of C. lacertoides varied from 2 to 6 eggs (3.75 ± 1.24, n = 15) and positive correlation between female SVL and clutch size was also observed (R 2 = 0.50; p < 0.001). Females of C. schreibersii had significantly larger SVL than mature males (t-test; p < 0.0001). Head length and width of mature females and males of C. schreibersii were not significantly different. Sexually mature females of C. lacertoides had significantly larger SVL than mature males (t test; p < 0.001), however, males had larger head than females, with significant differences in head length (Ancova; p < 0.001) and width (Ancova; p < 0.001). Juvenile females can attain the size of mature specimens after seven months for C. schreibersii and eight months for C. lacertoides. It was not possible to estimate the sexual maturation age of males, but it is possible to estimate that males are mature earlier and with smaller size than females in both species. Resumo: Foram analisadas as gônadas de 124 exemplares de Cercosaura schreibersii e 192 exemplares deCnemidophorus lacertoides do Escudo Sul-Riograndense, Rio Grande do Sul, Brasil. Ambas as espécies apresentaram reprodução tipicamente sazonal com fêmeas vitelogênicas no final do inverno e primavera, ovígeras na primavera e verão e o recrutamento ocorrendo nos meses com médias mais altas de temperatura na região. Não foi observada variação no volume médio ajustado dos testículos de machos de C. schreibersii ao longo do ano, contudo, o volume médio ajustado dos testículos de machos adultos de C. lacertoides alcançaram os maiores valores na primavera. Todas as desovas de C. schreibersii apresentaram número fixo de 2 ovos (n = 8) havendo correlação positiva entre o CRC das fêmeas e o tamanho dos ovos (R 2 = 0,55; p < 0,05). Em C. lacertoides o tamanho das desovas variou de 2 a 6 ovos ( x = 3,75 ± 1,24; n = 15) e foi observada correlação positiva entre o CRC das fêmeas e o tamanho das desovas (R 2 = 0,50; p < 0,001). Em ambas as espécies, fêmeas maduras apresentam CRC significativamente maiores que machos (Teste t; p < 0,001). Por outro lado, machos maduros apresentam o comprimento (Ancova; p < 0,001) e largura da cabeça (Ancova; p < 0,001) maiores que as das fêmeas. Fêmeas juvenis podem alcançar tamanho compatível ao d...

Natural history of Micrablepharus maximiliani (Squamata: Gymnophthalmidae) in a Cerrado region of northeastern Brazil

“…The presence of longer trunks in females may be associated with a fertility advantage conferred by a larger space in the peritoneal cavity for egg development (OLSSON et al 2002, COX et al 2003. A larger trunk length in females is recurrent in many species of Gymnophthalmidae (VITT 1982, VITT & ÁVILA-PIRES 1998, BALESTRIN et al 2010. On the other hand, males presented larger femoral and head lengths than females, a pattern that seems to be common in species of lizards in which the exploration or defense of territories by males, favors success in finding mates (PERRY et al 2004, PETERSON & HUSACK 2006, KALIONTZOPOULOU et al 2010.…”

“…Vanzosaura rubricauda (Boulenger, 1902) a related species, also shows multiple clutches of two eggs, with a continuous reproduction cycle in the Caatinga (VITT 1982), but a seasonal one in the Chaco (CRUZ 1994). A fixed clutch size of two eggs is a recurring pattern in many species of Gymnophthalmidae (FITCH 1970, TELFORD 1971, SHERBROOKE 1975, VITT 1982, ÁVILA-PIRES 1995, PIANKA & VITT 2003, BALESTRIN et al 2010.…”

Autoecology of Dryadosaura nordestina (Squamata: Gymnophthalmidae) from Atlantic forest fragments in Northeastern Brazil

“…ANDERSON & VITT (1990) suggested that head shape is directly related to facilitate mating because males can hold females tightly, besides providing advantages in male-male combat. Males with larger heads (than females) are also found in Cercosaura schreibersii Wiegmann, 1834(BALESTRIN et al 2010 and V. rubricauda (D.C.P.S. Aquino, unpubl.…”

<b>Biologia reprodutiva de <i>Enyalius perditus</i> (Jackson, 1978) e <i>Enyalius iheringii</i> (Boulenger, 1885) (Squamata: Leiosauridae)</b>

“…Despite the recent increase in the number of studies on the reproduction of Neotropical lizards (e.g., Balestrin et al, 2010;, the knowledge about the reproductive biology of several species is still scarce.…”