Overview
The Chaco Side-necked Turtle (Acanthochelys pallidipectoris) is an endangered chelonian endemic strictly to the harsh, seasonally arid Gran Chaco plains of northern Argentina, Paraguay, and Bolivia. Belonging to the family Chelidae, this hardy aquatic reptile folds its long, spiny neck horizontally beneath the rim of its shell rather than withdrawing it straight back, surviving in ephemeral water holes that evaporate during blistering dry seasons.
Biology and Physical Characteristics
Acanthochelys pallidipectoris possesses a flattened, oval carapace varying from pale horn-tan to dark brown, complemented by an unpatterned yellowish plastron that gives the species its Latin name pallidipectoris (‘pale-breasted’). Prominent, conical thorn-like tubercles line the soft skin of its thighs and neck, providing mechanical protection. Its webbed feet are armed with sharp claws designed for burrowing into drying pond silt.
Behavior and Ecology
To endure the extreme climatic fluctuations of the Gran Chaco—where searing droughts follow monsoon inundations—this turtle exhibits remarkable physiological resilience. When ephemeral lagoons dry out completely, individuals burrow beneath thick cracked clay or under thorn scrub leaf litter, entering prolonged dormant aestivation for up to six months until returning rains rehydrate the landscape.
Conservation and Human Impact
Listed as Endangered by the IUCN, the Chaco side-necked turtle faces severe population fragmentation. Massive deforestation of the Gran Chaco for industrial cattle ranching and soybean monocultures has eliminated vital wetland basins. Additionally, canalization, agricultural pesticide runoff, and occasional collection for international pet markets continue to threaten remaining wild populations.
Interesting Factoid
When summer heat dries up its muddy home in the Chaco, this resilient turtle buries itself deep into baking dry mud and enters a deep summer sleep called aestivation, waiting patiently for months until thunderstorms return!
Last updated: October 2026