Purple River Crabs Discovered on Philippine Island of Palawan

Posted on April 23, 2012

Scientists at the Senckenberg Research Institute in Dresden and De La Salle University in Manila have discovered four new species of colorful Insulamon freshwater crabs on the Philippine island of Palawan. The creatures include Insulamon palawanense, the purple crab pictured above.

Dr Hendrik Freitag from the Senckenberg Natural History Collections in Dresden, says, "We have proved that the only previously known type of Insulamon is restricted to the Calamian group of islands to the north of Palawan. The four newly discovered species live exclusively on the actual island of Palawan and make it a unique habitat."

The reddish violet species of the Insulamon crab genus are the only varieties that are endemic to only one or a few islands. Having been completely separated from their relatives, they have developed into their own separate species over tens of thousands of years. Sadly, the newly discovered crabs are already threatened by mining projects in the area.

Freitag says, "The smaller the remaining natural habitat the greater is the risk to endemic fauna and flora. Even minor environmental changes can lead to extinctions. It is all the more important to do research in this region and show that the biodiversity of these islands is unique and worth protecting, that's why our next step is to investigate Palawan's species-rich freshwater prawns."

The research paper, published in The Raffles Bulletin of Zoology, can be found here (PDF)

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