Boraras naevus has been in the aquarium hobby for several years now. © Peter Macguire

Three very different freshwater fishes are among ten animal and plant species highlighted in a new WWF report entitled ‘Extra Terrestrial’.

Among the 126 species newly identified by scientists in the Greater Mekong region in 2011 new were a bat named after its devilish appearance, a subterranean blind fish, a ruby-eyed pit viper, and a frog that sings like a bird.

“While the 2011 discoveries affirms the Mekong as a region of astonishing biodiversity, many new species are already struggling to survive in shrinking habitats,” said Nick Cox, Manager of the WWF’s Greater Mekong Species Programme.

Clarias gracilentus. © Ng Heok Hee

A new ‘walking’ catfish species Clarias gracilentus Ng, Hong & Tu 2011, discovered in freshwater streams on the Vietnamese island of Phu Quoc, can move across land using its pectoral fins to stay upright while it moves forward via snake-like movements.

A beautiful miniature fish, Boraras naevus Conway & Kottelat 2011, just 2cm in length, was found in southern Thailand and named after the large dark blotch on its golden body, naevus meaning ‘blemish’ in Latin.

It’s already known to aquarium hobbyists and is sometimes referred to as B. sp. ‘strawberry’ or B. sp. ‘red micros’.

Bangana musaei is a cave-dwelling cyprinid which lacks functioning eyes. © Helmut Steiner

A pearly, rose-tinted cyprinid  fish was discovered in the Xe Bangfai catchment, a Mekong River tributary in Central Laos that runs 7 km underground through limestone karst. The hypogean Bangana musaei Kottelat & Steiner 2011 is totally blind and was immediately assessed as vulnerable due to its restricted range.

The Mekong River supports around 850 fish species and the world’s most intensive inland fishery. Laos’ determination to construct the Xayaburi dam on the mainstream of the Mekong River is a significant threat to the Mekong’s extraordinary biodiversity and the productivity of this lifeline through Southeast Asia that supports the livelihoods of over 60 million people.

“The Mekong River supports levels of aquatic biodiversity second only to the Amazon River,” added Cox. “The Xayaburi dam would prove an impassable barrier for many fish species, signalling the demise for wildlife already known and as yet undiscovered.”

Proposed construction site for the Xayaburi Dam on the Mekong River in Northern Laos which the Laotian government are pressing ahead with despite opposition from neighbouring countries. © International Rivers

Extra Terrestrial spotlights 10 species newly identified by science, among the 82 plants, 13 fish, 21 reptiles, 5 amphibians and 5 mammals all discovered in 2011 within the Greater Mekong region of Southeast Asia that spans Cambodia, Laos, Myanmar, Thailand, Vietnam and the south-western Chinese province of Yunnan.

Since 1997, an incredible 1,710 new species from the Greater Mekong region have been described to science.

Click here to download the full report.

May we also extend congratulations to friends of SF Peter Macguire for his superb photos of Boraras naevus which are featured in the report, and Dr. Ng Heok Hee who co-described Clarias gracilentus.

The Mekong River at Luang Prabang, Laos. © Geo Swan

Laos has approved the construction of an enormous dam on the lower Mekong river, despite opposition from neighbouring countries, environmentalists, and locals. Continue reading »

Members of the family  Phallostethidae are small freshwater fishes native to Southeast Asia and included in the order Atheriniformes so related to rainbowfishes and ricefishes, among others.

They’re not popular aquarium fishes, but have an interesting reproductive strategy whereby males are equipped with a unique apparatus known as the priapium which is located on the underside of the head and used for clasping a female while simultaneously entering the body cavity and fertilising eggs internally. The female subsequently lays fully-fertilised eggs rather than giving birth to live young.

Freshly collected male (above) and female specimens of P. cuulong. © L. X. Tran

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