Socotra

A treasure in a treasure

a new skink from Socotra Archipelago

by Fabio Pupin

The Socotra Archipelago, in the north-west Indian Ocean, is considered to be one of the most biodiversity rich group of islands in the world, thanks to a very distinct fauna and flora with a high level of endemicity at both species and generic levels. For this reason, it has been designated as UNESCO World Heritage Natural site in 2008. Nevertheless, the natural history of most groups is still not clear, and their origin and evolution remain unknown. A team of researchers from the Department of Animal Biology (Università di Pavia, Italy), the Institute of Evolutionary Biology (CSIC-UPF, Barcelona, Spain), the Museo Civico di Storia Naturale di Carmagnola (Italy) and the Museum of Science of Trento (Italy), have been investigating the herpetofauna of the archipelago since 2007, in the framework of the ‘Socotra Conservation and Development Project’ funded by the Cooperazione Italiana and under the auspices of the United Nations Development Project (UNDP) to collect ecological data on the reptiles of the Socotra Archipelago in order to improve the sustainable development and conservation of the Socotra Archipelago’s biodiversity.
In a recent paper, the team presented some new highlights on the systematics, biogeography and evolution of Trachylepis socotrana, the only endemic reptile (a skink) supposed to live in all four islands (Socotra, Darsa, Samha and Abd Al Kuri). By comparing the skinks of the archipelago with representatives of the genus Trachylepis from Middle East, Africa and Madagascar plus some individuals from each of the other three genera of Mabuya skinks sensu lato (Chioninia, Eutropis and Mabuya), they have been able to trace back the history of the Socotran skinks. Interestingly, the results of the phylogenetic analyses indicate that members of the genus Trachylepis have landed in the archipelago in two independent events, firstly colonizing Socotra, Samha and Darsa about 10 million years ago, and then, 3 million years ago, colonizing Abd Al Kuri Island, when all the islands were already drifted away from the mainland. Furthermore, the Abd Al Kuri skink has proved to be a distinct new species, named by the authors Trachylepis cristinae, to credit the herpetologist who found the holotype while the team was surveying the island. This finding also means that reptiles of Abd Al Kuri, the westernmost island of the archipelago, are with no exceptions all exclusive of the island. Once again, the Socotra Archipelago proves to be one of the most unique places in the world to witness and investigate evolutionary processes, and indeed is worthy of its nickname of “Galapagos of the Indian Ocean”. And worthy of similar concern: as Kay Van Damme remarks in Nature – Middle East, Socotra has lost none of its unique terrestrial bird, reptile or mollusk species in the last century, contrary to what happened in many other islands in the world. Though, the archipelago is not invulnerable. Challenges include habitat fragmentation, over-exploitation and loss of traditional knowledge. Tourism, which exponentially increased in recent years, could also be a threat for the most protected –and thus visited- sanctuaries in the islands. But the main concern is nowadays represented by political instability that spreads across Middle East. As Van Damme underlines, political upheavals in Yemen will initiate changes in decision-making on long-term policies and conservation strategies that, in the end, will affect the Socotra Archipelago biodiversity for decades to come.

Field activity

Trachylepis cristinae

Trachylepis socotrana

Thanks to Roberto Sindaco, Cristina Grieco, Elisa Riservato, Salvador Carranza, Margarita Metallinou, Mauro Fasola, Francesca Pella

A new species of gecko from Socotra

by Fabio Pupin

With an astonishing number of endemisms, Socotra is one of the last biodiversity hot-spot of the planet, a tourist heaven for true nature-lovers and a unique meta for researchers. Since 1880 many zoologists have explored Socotra island, everytime coming back with new discoveries. Even today, the amazing biodiversity of the island doesn’t miss the chance to surprise. This year an Italian herpetological expedition described a new and still unnoticed species of gecko, called Hemidactylus inintellectus. Altough this little nocturnal gecko seems to be quite common on the island, herpetologist have always mistaken it with other similar species –that’s why the Italian team called him “misunderstood”-. This new discover rise up the number of reptile species of Socotra to 26, with 23 species endemic of the island. And this is not a mere matter of numbers: when a species has no name it doesn’t exist, and it can’t be protected. That’s why biodiversity assessments are such an essential tool for conservation policies.

Reference: Acta Herpetologica 4(1): 83-98, 2009

1 - Hemidactylus inintellectus

2 - Hemidactylus inintellectus

3 - Hemidactylus inintellectus

4 - Hemidactylus granti

5 - Hemidactylus granti

Thanks to Roberto Sindaco, Cristina Grieco, Elisa Riservato, Ugo Ziliani, Edoardo Razzetti, Mauro Fasola, Caterina Carugati, Francesca Pella, Eleonora Boncompagni, Marco Pavia, Irene Pellegrino, Daniele Pellitteri, Badr Awadh Al-Aseily, Ahmed Adeeb Abdullah, Michele Menegon.

Socotra: hic sunt dracones!

by Fabio Pupin

The island of Socotra, by far the largest of the homonymous archipelago off the Somali coast, is a resplendent jewel emerging in the Indian Ocean. Tourism has only recently landed on Socotra and altough the interest on this mysterious place is growing up, most of its secrets remains unveiled. Since centuries, travellers have described this island as a paradise on Earth, but today nothing more than few tales and pictures about the magnificent landscapes and bizarre plants have come back home. While bottle trees and other bizarre plants, such as the Dracaena cinnabari (the so-called “dragon blood tree”), are renowned anywhere in the world, other legitimate dragons go unnoticed: the Reptiles. Socotra is the home of some unique species, with 22 endemisms out of 25 species. Geckos are the most represented reptiles in the island: 6 species belong to the Semaphore geckos (genus Pristurus), 6 to the genus Hemidactylus and 2 to the endemic genus Haemodracon; but there are also other lizards, snakes and a chameleon. They are everywhere, from the high mountains of Haggeher to the desert lowland of the south coast, basking on tree branches as on nearly every rock around – and Socotra is a rocky place indeed! -. And even underground: there are, in fact, five worm-like reptiles, suited to a completely ctonian life. Although the herpetofauna of the island is considered to be relatively well known by scientists, new species have been described up to a few years ago and still most aspects of their life-history remain unknown. Thus, it’s not surprising that there are few images of these reptiles. Except maybe the Egyptian Vulture and some other birds, most of the animals of Socotra still wait to be celebrated. In 2007 and 2008 an Italian team of expert herpetologists started to collect ecological data on the reptile species (amphibians are completely absent from the Socotra archipelago), in the ongoing framework of the “Socotra Conservation and Development Project” (SCDP), with the aim of improving the sustainable development and conservation of the biodiversity of the island. I had the great opportunity to join the team and to dedicate my attention to the most ignored beauties of the island. The pictures you’ll see here are a brief selection of the many I collected during these field-trips (for an in-depth view of my pictures of Socotra click HERE).