Demonic Poison Frog
(Minyobates steyermarki)

Part of a family including the world’s most poisonous frogs, this small red frog is a restricted to one montane tepui on southern Venezuela, where this species is threatened by habitat destruction and over-collection for the pet trade. The demonic poison frog feeds on small invertebrates and lives in bromeliads. Pools of water, known as phytotelmata, form in the tightly-packed base of the bromeliad leaves, and this tiny frog has adapted to live in these water pools. Open cast gold mining, and its associated pollution and fires, is a major threat to the habitat of the demonic poison frog.

Urgent Conservation Actions
Measures to stop the illegal trade of this species; research into the ecology and population trends of the species is required.
Southern Venezuela
Poison frogs are traditionally used by the Emberá Chocó Indians to prepare poison darts. The frogs are first impaled on a piece of wood and then held over a fire until they cry out in pain. Bubbles of poison form as the frog's skin begins to blister. The dart tips are prepared by touching them to the toxin, or the toxin can be caught in a container and allowed to ferment. Poison darts made from either fresh or fermented batrachotoxin are enough to kill large prey, such as monkeys, birds or forest deer. Nerve paralysis is almost instantaneous. Other accounts say that a stick siurukida ("bamboo tooth") is put through the mouth of the frog and passed out through one of its hind legs. This causes the back of the frog to perspire profusely, and it becomes covered with a white froth. The darts are dipped or rolled in the froth, and the darts remain lethal for up to a year.

The demonic poison frog mates via cephalic amplexus, where the male grips the head of the female during mating, which is one of the factors that distinguishes it from its closest relatives.
Evolutionary Distinctiveness
Order: Anura
Family: Dendrobatidae
The Dendrobatidae (commonly referred to as the “poison frogs”) are undoubtedly some of the most vividly coloured members of the frog and toads. The colours and striking makings of these species indicate to any potential predators that they are extremely poisonous. In one case, the batrachotoxin poison contained in the golden poison frog (Phyllobates terribilis) is said to be sufficient to kill 50 men. Batrachotoxin is a neurotoxin which lethally affects the nervous system, and is one of the most potent poisons on Earth. The poison frogs diverged from all other amphibians 55 million years ago, and are therefore as different in terms of evolutionary time from their closest relatives as koalas and kangaroos. This family ranges from Nicaragua to Amazonian Bolivia, the Guianas, and southeast Brazil.

The demonic poison frog is the only species in its genus (Minyobates). Previously a number of other species had been allocated to Minyobates, but it was later shown that only the demonic poison frog exhibited cephalic amplexus (a mating embrace where the males clasps the female around the head as opposed to the body) and this frog also differs genetically from the species it was previously grouped with. The demonic poison frog is toxic, but not as lethal as some of the other species in its family.
This small frog grows to approximately 16 mm, although the males are slightly smaller in size than the females. The smooth skin has a dark red to reddish brown ground colour, with dark and light spots which can form a marbled pattern. Young have a pair of pale red streaks from the nose to the base of the back, which are lost as they age.
The demonic poison frog feeds on small invertebrates and lives in terrestrial bromeliads (a family of plants which includes the pineapple). Pools of water, known as phytotelmata, form in the tightly-packed base of the bromeliad leaves, and this tiny frog has adapted to live in these water pools.

Amplexus is cephalic, where the male holds the head of the female, which is one of the features which distinguishes this species from others in the same family. It is the male of the species which cares for the eggs, clutches of which vary in size from three to nine eggs, keeping the eggs moist. The eggs hatch at 10 to 14 days, when the larvae have reached approximately eight to ten millimetres in length. Tadpoles are black when the first hatch, but lighten as they grow until they are translucent red. On hatching, the male transfers the tadpoles one by one to the phytotelmata (water pools) where it takes up to seven weeks for them to mature into frogs.
The species is found in terrestrial bromeliads in montane tepui forest habitat, where the trees grow to approximately ten metres. Tepuis are isolated mountains, which generally have steep cliff sides and flat tops. These formations are distinct from the surrounding forest habitat, and are generally found in isolation, rather than in mountain-like ranges. Consequently, tepui often have a high number of endemic species.
The demonic poison frog is found only on the Cerro Yapacana tepui, not far from the Orinoco River in the state of Amazonas, Venezuela, at elevations of between 600 and 1,300 metres. This species has a total range area of less than 25 km sq.
Population Estimate
No numerical population estimate is known, however it has been reported that this frog is relatively common and easily found on the summit of the tepui.
Population Trend
This species is thought to be in decline by the IUCN Red List of Threatened Species.
The demonic poison frog is listed as Critically Endangered in the IUCN Red List of Threatened Species because its area of occupancy is probably less than 10 km sq., all individuals are in a single subpopulation, and the extent of its forest habitat on the Cerro Yapacana is declining.
Open cast gold mining, and its associated pollution and fires, is a major threat to the habitat of the demonic poison frog. The population has also suffered from collection of a number of specimens, some illegal including approximately 150 specimens which were sent to Germany, and some legally for scientific purposes. The effects of these threats are even more severe given the highly restricted range of this species.
Conservation Underway
The demonic poison frog is listed on Appendix II of CITES, meaning that trade in the species is regulated. Furthermore, Cerro Yapacana is a Venezuelan Natural Monument, which may offer some protection to the species.
Conservation Proposed
Further research into this relatively unknown species is required, including aspects of the biology and ecology of the species. In addition the population trend of the demonic poison frog should be monitored, and measures to prevent illegal trade need to be put into place.

In addition to conserving native habitat for this species, the IUCN Technical Guidelines for the Management of Ex situ Populations, part of the IUCN Red List of Threatened Species, recommend that all Critically Endangered species should have an ex situ population managed to guard against the extinction of the species. An ex situ population is ideally a breeding colony of a species maintained outside of its natural habitat, giving rise to individuals from that species that are sheltered from problems associated with their situation in the wild. This can be located within the species’ range or in a foreign country that has the facilities to support a captive breeding programme for that species. Since the demonic poison frog is categorised as Critically Endangered, the possibility of a captive breeding programme for this species should be investigated.
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