Reproductive biology and sexual dimorphism of a high-altitude population of the viviparous lizard Phymaturus punae from the Andes in Argentina

Abstract

Phymaturus punae is a viviparous lizard endemic to the Provincial Reserve San Guillermo, San Juan (Argentina). We present the first life history data of P. punae, belonging to an interesting genus adapted to cold climates. Females reach sexual maturity at 80.6 mm, and males at 84.4 mm snout-vent length. There is sexual dimorphism represented by larger and more robust males, but females show a wider body and a proportionally greater interlimb length than males. In males, spermatozoa become abundant in both testes and epididymi in mid-summer. Vitellogenic and pregnant females occurred simultaneously in late spring and mid-summer indicating a biennial reproductive cycle.

Field thermal biology in Phymaturus lizards: Comparisons from the Andes to the Patagonian steppe in Argentina

“…In addition, animals living in more-variable environments may have sharply reduced reproductive fitness when habitat quality is low (Martín and Ló pez, 1998). Accordingly, lizards of the genus Phymaturus living in arid environments at high altitudes and latitudes, with snowy winters and warm and dry summers, have been shown to be biennial, conducting vitellogenesis for 10-12 months followed by 4-5 months of pregnancy during the next activity season (Boretto and Ibargü engoyía, 2006;Boretto et al, 2007;Ibargü engoytía, 2004). In contrast, P. zapalensis, despite having low body temperature, is the only congener that can complete the reproductive cycle in 1 year, although they often skip years, probably caused by limitations on the ability to store fat reserves (Boretto and N.R.…”

“…The presence of tail injuries (cut or regenerated) was recorded. Individuals were assigned as juvenile, adult male and female by the presence of gametogenic features following Boretto and Ibargü engoytía (unpublished data), Boretto et al (2007), andIbargü engoytía (2004). Lizards were killed for further research in reproductive biology (see Boretto et al, 2007;Ibargü engoytía, 2004;Boretto and Ibargü engoytía, unpublished data) by intraperitoneal administration of sodium thiopental, fixed in Bouin's solution for 24 h or in 10% formaldehyde, and preserved in 70% ethanol.…”

How do viviparous and oviparous lizards reproduce in Patagonia? A comparative study of three species of Liolaemus

“…Under harsh environmental conditions, pregnant females of several viviparous reptiles adjust their thermal behaviours to maintain higher and more stable body temperatures than their environments (Avery, 1982;Shine, 2006). Likewise, reptiles have shown plasticity in the length of the reproductive cycles (Wapstra et al, 1999), prolonged female cycles (Cree, 1994), sperm reservoirs (Boretto and Ibargüengoytía, 2006), and the presence of abundant energetic reserves in the form of intraabdominal vitello and fat bodies (Boretto et al, 2007).…”

Hormones and Reproductive Cycles in Lizards

“…Multiennial reproduction occurs in a variety of lizards, including the viviparous New Zealand gecko, Hoplodactylus maculatus (Cree & Guillette, 1995); the oviparous Argentinean gecko, Homonota darwini (Ibargüengoytía & Casalins, 2007); viviparous ground lizards, Phymaturus patagonicus (Ibargüengoytía, 2004), Phymaturus antofagastensis (Boretto & Ibargüengoytía, 2006), Phymaturus punae (Boretto et al, 2007), and Liolaemus pictus (Ibargüengoytía & Cussac, 1996); and the viviparous blue-tongued skink, Tiliqua nigrolutea (Edwards, Jones, & Wapstra, 2002). This pattern may result when individuals skip a breeding season, or because it takes longer than a year to complete egg production or gestation.…”