Reproductive biology of a viviparous lizard (Mabuya dorsivittata) from the subtropical Wet Chaco of Argentina: geographical variations in response to local environmental pressures

ORTIZ, MARTÍN; BORETTO, JORGELINA; IBARGÜENGOYTÍA, NORA R.

ANAIS DA ACADEMIA BRASILEIRA DE CIENCIAS.

ACAD BRASILEIRA DE CIENCIAS

Año: 2019

0001-3765

Herein we studied the reproductive biology of a viviparous lizard (Mabuya dorsivittata) from the Wet Chaco region (northeastern Argentina) and comparedthe results with other populations from the Espinal (central Argentina) and theAtlantic Forest (southeastern Brazil), and with other Neotropical species of Mabuya to better understand the possiblecauses of its reproductive phenotype variation. Males and females of M. dorsivittata from the Wet Chacoexhibited associated, seasonal, and annual reproductive cycles. Spermatogenicactivity related positively to a lengthening photoperiod reaching maximumactivity in late spring (December). Females displayed an extended gestationperiod of 11 months, from mid-summer (February) to late spring or early summer (December)when births occur. Embryonic development was associated with temperature andhistorical rainfall. Litter size ranged from 3 to 8 (mean = 5.3 ± 1.3 SD) andincreased with body size and body mass of females. Fat-body mass variedseasonally and was inversely correlated with spermatogenesis and to embryonicdevelopment. Females were larger in body size and interlimb length, and smaller in head length than males. We observed interpopulational differences inminimum body size, litter size, and timing of birth, probably as a result ofphenotypic plasticity, genetic divergence or both.