Santa comes with gifts in the festive season – and this is for all of us: researchers have gifted three new species of fish to add to the already impressive list of freshwater fish in Sri Lanka, strengthening the country’s status as a global biodiversity hotspot. The new species emerge from Halmal Dandiya and Hora Dandiya and have been classified under genus Rasboroides (genus is a categorisation of species that have similar characteristics).
The discovery has come from the island-wide freshwater fish survey carried out by the Wildlife Conservation Society of Galle (WCSG) and Sri Lanka’s Biodiversity Secretariat (BDS). The aim of the survey was to study the prevalence of Sri Lanka’s endemic fish in their “type locations” – the place in which any species is first discovered and scientifically identified. The operation had two objectives: by studying the fish decades after their discovery in the same location allowed scientists to see if any changes had occurred in the intervening period and also to assess their conservation status.
As part of this survey, the endemic Halmal Dandiya or Sri Lanka Golden Rasbora (Rasboroides vaterifloris) discovered in 1930 in Ilukwatte, Gilimale was studied. Researchers also caught Halmal Dandiya from streams in other locations and carefully studied them. A specimen found in Kottawa, near Deniyaya showed characteristics distinct from the fish originally found from Gilimale.
“This has made us study the fish deeply and we found astonishing differences that encouraged us to carry out further research. This ended up in our separating two new species,” said WCSG President Madura de Silva.
The fish found in Kottawa Kobala forest reserve was named Rasboroides palida for its pallid colour. The other fish, discovered in Sooriyakanda, has been named as Rasboroides rohani to honour Rohan Petiyagoda who has carried out extensive research on Sri Lnka’s freshwater fish.
The research also established the existence of Sri Lanka Blackline Golden Rasbora or Kaluiri Halmaldandiya, scientifically known as Rasboroides nigromaginata. This fish was first identified in 1957 by a German, Meinken, based on specimens he found in his country. He pinpointed the source location of the fish as Sri Lanka, but this species has never before been reported alive in its natural environs.
Rasboroides vaterifloris still found in Gilimale
The discoveries have not ended there. The Horadandiya (Rasboroides atukorali) was declared a fish endemic to Sri Lanka in 1943 but an Indian researcher published a paper in the 1990s claiming that it came from India, so it was taken off Sri Lanka’s list of endemic fish. The research team thoroughly examined the features of both the Indian and Sri Lankan species and concluded that both countries have different species of Horadandiya, which reinstates the fish on Sri Lanka’s list.
The research findings were authored by Sudesh Batuwita, Madura de Silva and Udeni Edirisinghe in the latest edition of the international journal Ichthyological Exploration of Freshwaters.
Published on SundayTimes on 15.12.2013 http://www.sundaytimes.lk/131215/news/i-saw-three-fish-come-sailing...