New purple crab species found in Philippines

One of the four new species of freshwater crab is pictured
This handout photo released by Hendrik Freitag, of Germany's Senckenberg Museum of Zoology shows one of the four new species of freshwater crab found in remote areas of the Palawan island group. The tiny crustaceans were found in streams in remote areas of the Palawan island group, according to a team led by Freitag.

Four new species of freshwater crab, bright purple in colour, have been discovered in the biologically diverse but ecologically-threatened Philippines, the man who found them said Saturday.

The tiny crustaceans burrow under boulders and roots in streams, feeding on dead plants, fruits, carrion and in the water at night, said Hendrik Freitag of Germany's Senckenberg Museum of Zoology.

Found only in small, lowland-forest ecosystems in the Palawan island group, most have purple shells, with claws and legs tipped red.

"It is known that crabs can discriminate colours. Therefore, it seems likely that the colouration has a signal function for the , e.g. mating," Freitag told AFP by email on Saturday.

"This could explain why large males of various Insulamon species are more reddish compared to the generally violet females and immature males."

Scientists began extensive investigations of similar freshwater crabs in the area in the late 1980s, when one new species was found -- the Insulamon unicorn, Freitag said.

More field work led Freitag to conclude there were four other unique species.

"Based on available new material, a total of five species are recognised... four of which are new to science," Freitag wrote in the latest edition of the National University of Singapore's Raffles Bulletin of Zoology.

The carapace of the biggest, Insulamon magnum, is just 53 millimetres by 41.8 millimetres while the smallest, Insulamon porculum, measures 33.1 by 25.1 millimetres.

The two other new species were called Insulamon palawense and Insulamon johannchristiani.

The four slightly differ from the first find, and from each other, in the shapes of their body shells, legs, and sex organs.

US-based Conservation International lists the Philippines as one of 17 countries that harbours most of Earth's plant and animal life.

Reptiles, birds or mammals likely prey on the , and it is possible people in remote areas also collect them for food, Freitag said.

However, the main threats are the ongoing forest clearing for farming, mining or home building, since this risks drying up their small habitats and causes water pollution, he said.

"Even if the habitats are not entirely destroyed, the smaller the remaining habitats, the higher the risk of extinction for a ," he said.

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(c) 2012 AFP

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User comments

Apr 22, 2012
looking so fabulous, that creature is just waiting to get gay-bashed!

Apr 22, 2012
I must have one.

Apr 22, 2012
And not too far away from where it was found, they are dynamite fishing and destroying the reef...

Apr 22, 2012
Could allowing them to be traded as pets keep them alive as a species? Would that be more destructive or constructive?

Apr 22, 2012
thats pimp daddy in his new kandi color ride

Apr 23, 2012
The purple colour is probably a warning that it's poisonous and non-edible. But, I could be wrong.

Apr 24, 2012
Could allowing them to be traded as pets keep them alive as a species? Would that be more destructive or constructive?

Possibly, but species die all the time before we are able to discover them. The only real way to protect their habitat is with guns, and just shoot anybody who comes to poach them.

However, because they are small, they might make a good addition to many salt water tropical aquariums. They could eat all of the biomass which falls to the bottom of the tank, and then use it for whatever they want to use it for.

Apr 29, 2012
Personally, I would be cautious about trying to eat anything with bright colours, such as this crab. We all know that bright colours are often associated with a considerable degree of poison in nature. For all we know, this crab could be highly toxic. Just a suggestion, however. It could be wrong.

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