Acanthochelys macrocephala
Chelidae·Snails form a large part of this turtle's diet.·Near Threatened·hard-shelled
The big-headed pantanal swamp turtle (Acanthochelys macrocephala) is a species of turtle found in Brazil, Bolivia, Argentina, and Paraguay. Distinctive for its extremely broad head, it is the largest species within the Acanthochelys genus, reaching up to 23.5 cm in carapace length. This species inhabits marshes, swamps, and slow-flowing streams.
Key Facts
- ›It is the largest species of the Acanthochelys genus, with a carapace length up to 23.5 CM.
- ›The species is characterized by an extremely broad head, which is proportionally larger in older females.
- ›Its natural habitat includes marshes, swamps, and slow-flowing streams.
- ›The diet primarily consists of snails.
- ›Nesting occurs near the end of the wet season (April-May), with hatchlings emerging between December and March.
- ›The IUCN status is listed as near Threatened, though the Chaco population is considered Vulnerable.
- Largest of the South American Acanthochelys Species, Growing To 23.5 Cm In Carapace Length.
- Broad, Oval To Moderately Elongated, Deep Carapace With A Shallow Dorsal Groove.
- Extremely Broad Head, With Older Females Potentially Developing Massive Heads.
- Carapace Is Dark To Blackish Brown, Sometimes With Lighter Brown Radiations On Scutes In Juveniles.
- Plastron and Bridge Are Yellow With Fading Dark Pigment Along the Seams.
- Head Is Dark Grayish Brown Above, Yellow Or Cream Below.
- Two Chin Barbels Present.
- Neck Is Grayish Brown Dorsally, Yellow Ventrally, With Scattered Blunt, Conical Tubercles.
- Limbs Are Gray On the Outside, Yellow Beneath, and Covered With Large Scales.
- Large Conical Tubercles On the Inside of Each Thigh.
- Females Are Larger and More Domed; Males Have Slightly Concave Plastra and Longer, Thicker Tails.
- Females Are Larger and More Domed Than Males.
- Males Have Slightly Concave Plastra and Longer, Thicker Tails.
About Acanthochelys macrocephala
The big-headed pantanal swamp turtle, scientifically known as Acanthochelys macrocephala, is a species of turtle belonging to the family Chelidae. This species is primarily found in the river basins of Brazil, Bolivia, Argentina, and Paraguay, inhabiting environments such as marshes, swamps, and slow-flowing streams.
Physical Characteristics
Acanthochelys macrocephala is distinguished by its exceptionally broad head, which gives it its common name. It is the largest species within the Acanthochelys genus, with adults typically reaching a carapace length of up to 23.5 cm (9.3 inches). The carapace is broad, oval to moderately elongated, and deep, with a color ranging from dark to blackish brown. Juveniles may exhibit lighter brown radiations on their carapacial scutes. The plastron and bridge are yellow and often display fading dark pigment along the seams. The head is dark grayish brown on the dorsal side and yellow or cream ventrally, with two chin barbels. The neck is grayish brown dorsally and yellow ventrally, featuring scattered blunt, conical tubercles. Limbs are gray externally and yellow beneath, covered in large scales, with prominent conical tubercles on the inner thighs.
Sexual dimorphism is present, with females generally being larger and having more domed carapaces. Males, in contrast, possess slightly concave plastra and tend to have longer, thicker tails.
Diet and Reproduction
Snails constitute a significant portion of the Acanthochelys macrocephala's diet. Reproduction typically begins near the end of the wet season, with nesting occurring in April and May. Females lay clutches of 4 to 8 hard-shelled eggs, which are white and rounded. The incubation period exceeds six months, and hatchlings, which emerge between December and March, are characterized by orange-red spots on their carapace, plastron, and neck.
Distribution and Conservation
This species is found in the upper Rio Mamoré drainage of central Bolivia, the Pantanal region and swamplands of the upper Rio Paraguay drainage in southwestern Mato Grosso, Brazil, and extends into the Chaco region of Paraguay. The conservation status of Acanthochelys macrocephala is listed as Near Threatened by the IUCN. A distinct population in the Chaco, sometimes referred to as Acanthochelys chacoensis, is classified as Vulnerable, indicating a higher level of concern for its long-term survival.
Source: Wikipedia ↗
Frequently Asked Questions
What are the main countries where the big-headed pantanal swamp turtle is found?
The Acanthochelys macrocephala is found in Brazil, Bolivia, Argentina, and Paraguay. Its range may extend further in Bolivia, and it inhabits the Pantanal region and other swamplands.
What are the distinctive physical features of Acanthochelys macrocephala?
This turtle is recognized by its extremely broad head and is the largest of the Acanthochelys species, reaching up to 23.5 cm in carapace length. The carapace is broad, oval to moderately elongated, and dark to blackish brown, while the plastron is yellow with fading dark pigment.
What is the natural diet of the big-headed pantanal swamp turtle?
Snails form a significant portion of the Acanthochelys macrocephala's diet. This dietary preference is a key characteristic of the species' natural feeding habits.
When does Acanthochelys macrocephala reproduce and lay eggs?
Nesting for this species begins near the end of the wet season, typically in April or May. The eggs are hard-shelled, white, and rounded, with hatchlings expected to emerge between December and March.
What is the conservation status of the big-headed pantanal swamp turtle?
The Acanthochelys macrocephala is listed as Near Threatened by the IUCN. However, a specific population in the Chaco region, sometimes listed as Acanthochelys chacoensis, is designated as Vulnerable.