The newly-identified species belong to the gecko subgenus Domerguella in the genus Lygodactylus, and each of them is no longer than your pointer finger.
The reptiles of Madagascar, as the island’s entire fauna and flora, are characterized by high species diversity and a striking number of endemics.
Although distribution, ecology and reproduction of several reptile groups have been studied more intensively than those of other animal groups, the majority of species are still incompletely known.
This is also reflected by a lack of taxonomic information, indicated by numerous deep genetic lineages still not revised and scientifically named.
These candidate species are relatively evenly distributed across all main groups of Malagasy reptiles, and consequently, many recent studies revised and named single or a limited number of new species, for instance in geckos.
One group of Malagasy reptiles with a disproportionately high number of candidate species is the genus Lygodactylus.
These dwarf day geckos consist of over 70 currently described species across Africa, Madagascar, and parts of South America.
In Madagascar, over 20 species are currently known. Most of them belong to the subgenus Domerguella.
“Domerguella are tiny, at just 5 to 7 cm (2-2.8 inches) from the nose to the tip of the tail,” said Dr. Mark Scherz, curator of herpetology at the Natural History Museum of Denmark.
“We think that their small size may play a role in the way they speciate.”
“Because small animals are generally less able to move from one area to another, and are more likely to get isolated by barriers like rivers cropping up between populations.”
“This could explain why we have seen these kinds of patterns in the tiny frogs, chameleons, and now also geckos that we have been studying in Madagascar.”
The newly-identified species are Lygodactylus tantsaha, Lygodactylus salvi, Lygodactylus roellae, Lygodactylus hapei, Lygodactylus winki, Lygodactylus ulli, Lygodactylus fritzi, and Lygodactylus hodikazo.
“This was a remarkable discovery,” said Professor Miguel Vences, a researcher at the Technische Universität Braunschweig.
“On Montagne d’Ambre in the north of Madagascar we thought we were collecting just one species, but now we find there are four.”
“Four different, closely related species that are almost indistinguishable to us, occurring together in the same place, apparently without interbreeding — this is exceptional, even for Madagascar.”
“These results highlight how important it is that we continue to collect samples across Madagascar, even of species we think we understand. There is still very much more to discover,” added Dr. Frank Glaw, curator of herpetology at the Zoologische Staatssammlung München.
“The five species we knew before were mostly thought to be unthreatened, but the eight new species are all either probably endangered or critically endangered,” said Dr. Fanomezana Ratsoavina, a researcher at the University of Antananarivo.
“This shows how important it is to continue to work to discover, describe, and assess the conservation status of the wildlife of Madagascar.”
A paper describing the discovery was published in the journal Zootaxa.
Miguel Vences et al. Integrative revision of the Lygodactylus madagascariensis group reveals an unexpected diversity of little brown geckos in Madagascar’s rainforest. Zootaxa, published online September 1, 2022; doi: 10.11646/zootaxa.5179.1.1
Source link: https://www.sci.news/biology/eight-new-lygodactylus-species-11158.html