30-07-2025
Island creature — with vibrant orange belly — is a new species in Madagascar
Under the cover of darkness, a group of researchers searched the northern forests of Madagascar for a small lizard.
Moving between burnt trees in a densely packed forest, they noticed the little animals 'sleeping … on twigs or small branches,' and stopped for a closer look.
The animals belong to a genus of geckos called Lygodactylus, or dwarf geckos, and were found to belong to species new to science, according to a study published July 23 in the peer-reviewed journal Zootaxa.
Researchers found one of these new species in Baie De Baly National Park, a peninsula on Madagascar's northwestern coast, according to the study.
The tail of the gecko is slightly longer than the rest of the body — 1.1 inches long compared to a body length of 1 inch – accounting for half of the animal's total size, researchers said.
The species, named Lygodactylus arnei, can be distinguished from other dwarf geckos by the vibrant orange color on the bottom of its tail, stretching to its belly and sometimes its chest, according to the study.
The rest of its underside is white, researchers said, while its back is slightly blue-gray in color with bands of white and brown coloring.
Overall, the gecko is a bit wider than other species and has 'relatively large' eyes for its head, according to the study.
'The species name is a patronym for the wildlife photographer and gecko specialist Arne Hartig, in recognition for his contributions to the exploration of Madagascar's gecko fauna and the important support he provided for this study by making photos and information from his previous Namoroka expeditions available,' researchers said.
The Arne Hartig dwarf gecko is arboreal, meaning it spends most of its life in trees, in a generally dry area, according to the study.
In Baie de Baly National Park, a large number of trees were partially burnt about a year before the new species was found, according to the study, but while the smaller trees were dead and the leaf litter was scorched, many of the larger trees appeared in good condition.
The new species was also found in two other regions of Madagascar, both within about 30 miles of the national park, researchers said.
'In the Tsiombikibo Forest, L. arnei has been found in a forested area where trees are relatively small and densely implanted, and where a relatively thin layer of leaf litter mostly rests on a bed of almost pure white sand,' researchers said. 'In Namoroka, this species has been more frequently found on tree trunks – or at their base, close to the leaf litter – growing in the border of the Tsingy karstic formation.'
The 'tsingys' refers to an area of northwestern Madagascar covered with towering rock formations that look like shards of stone placed vertically in the ground.
The name translates to 'where one cannot walk barefoot' in Malagasy, and the region provides a home to a high diversity of lizards, including other dwarf geckos. The Arne Hartig dwarf gecko was one of three new species found during the same 2023 expedition included in the study.
The research team included Miguel Vences, Cecilia Herrmann, Malte Multzsch, Sven Gippner, Delina Razafimanafo, Ny Ando Rahagalala, Sandratra Rakotomanga, Andolalao Rakotoarison, Frank Glaw and Aurélien Miralles.
