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Adelphobates castaneoticus

The Brazil-nut poison frog (Adelphobates castaneoticus) is a small, vibrantly colored frog endemic to the state of Pará in Brazil. It is distinguished by its unique breeding behavior, where males transport tadpoles to water-filled Brazil nut husks, creating a complex micro-ecosystem for development. This species is diurnal and inhabits the rainforest floor.

Key Facts

  • Endemic to the state of Pará, Brazil.
  • Small size, with snout-to-vent length between 18-23 MM.
  • Dorsal surface is shiny black with white or yellow spots and markings.
  • Males transport tadpoles to water-filled Brazil nut husks for development.
  • Diurnal, feeding on ants, termites, and other small invertebrates.
  • IUCN conservation status is 'least concern'.
Adelphobates castaneoticus
Scientific Name
Adelphobates castaneoticus
Family
Dendrobatidae
Common Names

Brazil-Nut Poison Frog

Description
The Brazil-nut poison frog is a very small amphibian, typically measuring between 18 to 23 mm in snout-to-vent length, with females generally being larger than males. Its dorsal surface is a striking shiny black, adorned with spots and markings in white or various shades of yellow. A distinctive bright yellow or orange spot is present where the foreleg meets the body, with two similar spots near the knee joint on the hind legs that merge into one large spot when the frog is still. An additional spot on the underside of the calf is only visible when viewed from below.
Habitat Description
This species is found in the rainforest of central Brazil, specifically within the state of Pará. It inhabits the leaf litter on the forest floor and is also known to climb into low vegetation. A critical element of its habitat involves the presence of empty Brazil nut husks which can collect rainwater and serve as crucial breeding sites for its tadpoles.
Diet
The Brazil-nut poison frog is diurnal and feeds on ants, termites, and other small invertebrates. Its tadpoles, once deposited in water-filled husks, consume mosquito larvae, smaller tadpoles, and other small aquatic creatures, as well as suitable plant material.
Breeding Behavior
The male Brazil-nut poison frog guards the eggs laid on the ground. Upon hatching, he transports the tadpoles to temporary pools, notably to water-filled empty husks of Brazil nut fruits. These husks create a small but complex ecosystem where tadpoles of various species compete for survival.
Size Range Mm
18-23
Habitat Type

Rainforest, Forest Floor

Distribution States

Pará

Distinguishing Features
  • Shiny Black Dorsal Surface With White Or Yellow Markings.
  • Bright Yellow/Orange Spot At the Base of the Foreleg.
  • Yellow/Orange Spots On the Hind Legs Near the Knee.
  • Small Size.

About Adelphobates castaneoticus

Adelphobates castaneoticus: The Brazil-nut Poison Frog

The Brazil-nut poison frog, scientifically known as Adelphobates castaneoticus, is a diminutive amphibian native to the state of Pará in Brazil. Its common name is a direct reference to its remarkable breeding strategy, which often involves the use of empty Brazil nut husks as nurseries for its young.

Description and Habitat

This frog is characterized by its small stature, with adults typically measuring between 18 to 23 millimeters in snout-to-vent length. Females tend to be slightly larger than males. The dorsal surface is a glossy black, punctuated by distinctive spots and markings of white or various shades of yellow. Notable coloration includes a bright yellow or orange spot where the foreleg attaches to the body, and similar, often confluent, spots on the hind legs near the knee. A further spot is visible on the underside of the calf. The Brazil-nut poison frog resides in the rainforest environment of central Brazil, dwelling amongst the leaf litter on the forest floor and occasionally venturing into low-lying vegetation.

Biology and Reproduction

Adelphobates castaneoticus is a diurnal species, meaning it is active during the day. Its diet consists primarily of ants, termites, and other small invertebrates. The reproductive cycle is particularly fascinating. Eggs are laid on the ground and are guarded by the male. Once hatched, the male amphibian carries the tadpoles to temporary water pools. A preferred and distinctive site for this is the water that collects within the empty husks of Brazil nut fruits, which are abundant in its habitat. These husks form miniature, ephemeral aquatic ecosystems where the tadpoles develop, feeding on mosquito larvae and other small organisms.

Distribution and Conservation

The species is endemic to the state of Pará, Brazil, with known occurrences in areas such as Cachoeira Juruá, the Xingu River region, Taperinha, and Flona Tapajos. While its distribution might be more extensive than currently documented, it is considered common within its known range. The International Union for Conservation of Nature (IUCN) lists the Brazil-nut poison frog as 'least concern,' indicating that it is not currently facing immediate threats of extinction. However, potential threats include logging, habitat destruction due to agricultural expansion, and wildfires. Several conservation areas within its range help protect its habitat.

Source: Wikipedia ↗

Frequently Asked Questions

What is the common name for Adelphobates castaneoticus?

The common name for Adelphobates castaneoticus is the Brazil-nut poison frog. This name is derived from its unusual breeding habit of utilizing empty Brazil nut husks.

Where is the Brazil-nut poison frog found?

The Brazil-nut poison frog is endemic to the state of Pará in Brazil. It is found in the rainforest, specifically in areas like Cachoeira Juruá, Xingu River, Taperinha, and Flona Tapajos.

How does the Brazil-nut poison frog reproduce?

The male Brazil-nut poison frog lays eggs on the ground and guards them. After hatching, he carries the tadpoles to temporary water sources, most notably water-filled empty Brazil nut husks found on the forest floor, where they develop.

What does the Brazil-nut poison frog eat?

The Brazil-nut poison frog is diurnal and feeds on a diet of ants, termites, and other small invertebrates. Its tadpoles, developing in the Brazil nut husks, consume mosquito larvae and other small creatures.

What is the conservation status of the Brazil-nut poison frog?

The Brazil-nut poison frog is listed as 'least concern' by the IUCN. While common within its range, threats such as logging and habitat destruction exist.