The number of fish species in Myanmar grew by 17 last year, of which eight were due to the detective skills of Natural History Museum ichthyologist (fish expert), Dr Ralf Britz.
Ralf described two snakeheads, three eel-loaches and two spiny eels, all of which are popular aquarium fish. He also resurrected a forgotten species of eel loach. So, seven species were described for the first time.
Some were gathered during Ralf's scientific expeditions to the Southeast Asian country last year, and others were identified from samples collected in previous expeditions or from other specimen collections.
Myanmar, previously called Burma, has many remote and unexplored regions. In some places, Ralf and his team were the first scientists to collect scientific specimens and one of the new species was found only in a particular stream that was less than five miles long.
2007 was indeed a bumper year for fish discoveries in Myanmar with 17 being the highest since 1990. There was only one discovery in 2006, 6 in 2005 and 11 in 2004.
Snakeheads are torpedo-shaped fish, usually about 12-120cm in size. They live in freshwater rivers, streams, and lakes and some species are oral brooders, meaning they raise their young in their mouths.
Head of new dwarf snakehead species Channa ornatipinnis.
The small size and pretty colours of some species make them popular among fish-keepers. The new species Ralf identified were unusually colourful dwarf snakeheads.
'There are only 30 species of snakeheads,' says Ralf, 'and when I saw the colour pattern of the one from Waloun Chaung in the net, I knew straight away that this was a new species.'
After collecting the fish samples, Ralf took them to the Museum for more detailed study and to compare them with specimens in the Museum's collection.
Ralf analysed the number of fin-rays and scales and the colour patterns of the fish. The fishes had not been described before so Ralf could confirm they were two new species. He named them Channa ornatipinnis (ornatipinnis means with ornate fins) and Channa pulchra (pulchra means beautiful).
If a scientist thinks they have identified a new species, they write up their detailed analysis, with suggested names for the new species, and then send this to a scientific journal.
Other experts in that scientific field review the manuscript and once they are in agreement, the description can be accepted and published and the newly-named species is 'created'.
Kuhli, or eel-loaches are small, eel-shaped fish that live in the sandy beds of slow-moving rivers and streams. They belong to the genus Pangio and there are only 25 species in this group. They are popular aquarium fish and are often found hidden under gravel or sand at the bottom of the tank.
New species of eel-loach, Pangio lumbriciformis.
Once the samples of eel-loaches were collected, they were brought back to the Museum. They don't show any colourful patterns, like snakeheads, that could be used to distinguish species, so Ralf took radiographs to analyse the loaches in more detail (radiographs are photos taken by exposing film to X-rays that penetrate the body of the fish and make the skeleton visible, see image at top of page).
The number of fins and vertebrae were counted and then compared with those of other specimens in the Museum's collection and with those borrowed from other museums.
Ralf and his colleague, James Maclaine, found out that there were four new species of eel-loaches. Ralf named them Pangio lumbriciformis (see image at top of page, lumbriciformis means like a worm), Pangio signicauda (signicauda means a mark on the tail), Pangio apoda (apoda means without legs) and Pangio elongata (elongata means elongate).
'We were quite surprised to find three new species of Pangio in Myanmar,' Ralf adds. 'This basically quadrupled their diversity there, as only one species was known before from that country.'
Spiny eels are medium to large eel-like fish that, unlike true eels, have a large series of isolated fin spines on their back. They are important food fishes in Asia, but the smaller species are also popular among aquarists.
Ralf studied larger samples of spiny eels from Myanmar that he and his colleagues had collected. He discovered two undescribed species among the material by using clear differences in the colour pattern and the number of vertebrae to distinguish the new species from already described ones.
Mastacembelus pantherinus (pantherinus is referring to the panther-like colouration) and Mastacembelus tinwini (tinwini is named after a Myanmar fish exporter who helped discover the new species) belong to the larger species that reach up to at least 40cm in length.
Ralf concludes, 'When it comes to freshwater fishes, Myanmar is still a poorly explored country and a total of 60 new species have been described from there since 1990. I have little doubt that I will return from my next collecting trip to Myanmar with a significant number of new species.'