Reproduction and sexual dimorphism of Lepidophyma sylvaticum (Squamata: Xantusiidae), a tropical night lizard from Tlanchinol, Hidalgo, Mexico

Abstract

We studied reproductive characteristics of the night lizard, Lepidophyma sylvaticum (Xantusiidae) from cloud forest in Tlanchinol, Hidalgo, Mexico. Males reached sexual maturity at a snout-vent length (SVL) of 55 mm, and females reached sexual maturity at a SVL of 56 mm. Males and females were not sexually dimorphic in SVL, but males had significantly larger heads and limbs than females. Reproduction in males and females was seasonal. Testicular mass increased in July and August, reaching maximum size in September. Minimum testes size occurred in March. Follicles of females began to increase in size in September when vitellogenesis was observed. Follicles in some females increased in mass during January-March, whereas other females ovulated during that period. Late embryonic stages (35-40) were observed in July with parturition likely occurring in July and August, coincident with maximum rainfall. Litter size averaged 4.7 ± 0.4 neonates, and was not correlated with female size. Similarities in reproductive characteristics between L. sylvaticum and other xantusiids (viviparity, long gestation period) suggest that some reproductive characteristics have a historical origin.

Reproduction in the Yellow-spotted night lizard, Lepidophyma flavimaculatum (Squamata, Xantusiidae), from Costa Rica

“…My samples are too small to completely elucidate the seasonal testicular cycle of L. flavimaculatum as one each spermiogenic male came from Limón and Heredia Provinces, nevertheless these preliminary data indicated a late-summer to autumn period of sperm formation. This appears similar to the timing of the testicular cycles of other species of Lepidophyma: L. gaigae (Goldberg and Camarillo-Rangel 2003), L. sylvaticum (Ramírez-Hernández 2003, Ramírez-Bautista et al 2008 and L. pajapanensis (Méndez-de La Cruz et al 1999) in which males are reproductively active in summer to autumn. It thus appears from my results and other studies on congeneric species that Lepidophyma males undergo a late-summer to autumn period of sperm formation This timing differs from males of the xantusiid lizards, Xantusia vigilis (Zweifel and Lowe 1966) a desert species, and Xantusia riversiana (Goldberg and Bezy 1974), an island species in which mating occurs in spring.…”

Atypical reproductive cycles in a population of Sceloporus grammicus (Squamata: Phrynosomatidae) from the Mexican Plateau

“…, ), Anguidae (Guillette and Casas‐Andreu ), and Xantusiidae (Ramírez‐Bautista et al. ). In such systems, mating occurs several months prior to ovulation, and sperm transfer is thus temporally uncoupled from fertilization.…”

“…At the proximate level, temporal differences in the onset of reproductive activity (i.e., reproductive asynchrony) in males and females can arise if the sexes use different environmental cues to initiate reproductive activity (Guillette ; Ramírez‐Bautista et al. ,b).…”

“…Viviparous species, on the other hand, produce only one clutch per year (Guillette , ; Ramírez‐Bautista et al. ,b). One possible benefit is that female sperm storage may not be necessary in Tepeapulco, as has been hypothesized for other synchronously breeding populations of S. grammicus (Ortega and Barbault ) and S. grammicus disparilis (Guillette and Bearce ).…”

Hormones and Reproductive Cycles in Lizards

“…Xantusiids mate in the fall, with gestation and birth occurring in late summer or early fall of the following year (Aguilar Cortés, Camarillo, & Bezy, 1990;Ramírez-Bautista, Vitt, Ramírez-Hernandez, Quijano, & Smith, 2008). They are small in body size (typically 0.5 cm snout-to-vent length or less), long-lived (around 10 years for some species), and viviparous .…”