''Allobates chalcopis'', also known as the Martinique volcano frog or ravine rocket frog, is a species of

frog A frog is any member of a diverse and largely carnivorous group of short-bodied, tailless amphibians composing the order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-frog" ''Triadobatrachus'' is ...

in the family

Aromobatidae The Aromobatidae are a family of frogs native to Central and South America. They are sometimes referred to as cryptic forest frogs or cryptic poison frogs. They are the sister taxon of the Dendrobatidae, the poison dart frogs, but are not as to ...

. It is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

Martinique Martinique ( , ; gcf, label=Martinican Creole, Matinik or ; Kalinago: or ) is an island and an overseas department/region and single territorial collectivity of France. An integral part of the French Republic, Martinique is located in ...

, where it is found at high-altitude areas including

Mount Pelée Mount Pelée or Mont Pelée ( ; french: Montagne Pelée, ; gcf, label=Antillean Creole, Montann Pèlé, meaning "bald mountain" or "peeled mountain") is an active volcano at the northern end of Martinique, an island and French overseas departmen ...

and potentially most of the

Carbet Mountains The Carbet Mountains (, or ''Carbet Nails'') are a massif of volcanic origin on the Caribbean island of Martinique. The mountain range is a popular tourist, hiking, and rock climbing destination. Geography The scenic Carbet Pitons range occupy ...

. It is threatened by

climate change In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to ...

, which has led to it being extirpated from the lower-lying reaches of its already-small range, and may lead to a continued population decline and range contraction. ''Allobates chalcopis'' is the only aromobatid species

to an oceanic island. This has led to a suggestion that it is not native but an introduced species, synonymous with some mainland species. However, examination of new specimens with

molecular phylogenetics Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...

methods suggests it is truly distinct from the mainland ''Allobates'', and highly diverged from its closest relatives. This conclusion is also supported by morphological and ecological evidence, thereby strengthening the position that it is a true endemic.

Description

''Allobates chalcopis'' is a small frog with males measuring about in snout–vent length and females about . Its dorsum is light brown with darker markings. Males have a distinctive, black throat, tapering off to a dark gray, whereas females have uniformly pale orange throat and venter. The

tadpole A tadpole is the larval stage in the biological life cycle of an amphibian. Most tadpoles are fully aquatic, though some species of amphibians have tadpoles that are terrestrial. Tadpoles have some fish-like features that may not be found ...

s are terrestrial, free-living, and endotrophic—they do not feed but rely on stored yolk. They grow to a length of at least . The body is ventrally flattened.

Habitat

''Allobates chalcopis'' was originally described from forested ravines of

at an elevation of about asl. Extensive search in 2011 failed to spot the species in this habitat, but it was discovered higher up on the mountain, at about asl, that is, to the summit of the mountain. The current range starts from the transition zone between forest and savanna, the latter being the vegetation type found higher up on the mountain. A 2012 survey also found it on Piton Boucher, a member of the

to the southeast of Pelée, at 1,000 m asl. Although not yet surveyed, it may be present on other peaks of the Carbet Mountains

massif In geology, a massif ( or ) is a section of a planet's crust that is demarcated by faults or flexures. In the movement of the crust, a massif tends to retain its internal structure while being displaced as a whole. The term also refers to a ...

Conservation

The

International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of nat ...

assessed ''Allobates chalcopis'' in 2010 as Vulnerable. However, in light of its disappearance from the lower altitudes due to climate change and the very small remaining range (and the evidence of endemicity), it was reclassified as Critically Endangered in 2021.

References

{{Taxonbar, from=Q1343441 chalcopis Amphibians of the Caribbean Endemic fauna of Martinique Amphibians described in 1994 Taxonomy articles created by Polbot Critically endangered biota of North America