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Researchers discover new variant of Sri Lankan aquarium fish

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by Ifham Nizam

A new variant of a popular Sri Lankan aquarium fish has been discovered by local and foreign researchers.

The freshwater fish, genus Rasbora, (commonly called ‘dandiya’) is one of the most diverse groups of freshwater fishes in tropical Asia.

In Sri Lanka, previous studies have shown that there are five species (Rasbora dandia, R. microcephalus, R. wilpita, R. naggsi, and R. armitagei) of which the last three are endemic to the island. This diversity is remarkable when compared with peninsular India, which is about 25 times the size of Sri Lanka but contain only four species of Rasbora.

Biologists earlier believed there were only five varieties of the popular aquarium fish endemic to Sri Lanka. However, with the discovery of the sixth species, Rasbora has gained a new reputation among Sri Lankan freshwater fish breeders, hobbyists and harvesters.

The researchers carried out multiple analysis using “finer geographic sampling and greater sample sizes”, thereby corroborating the validity of six species of Rasbora (scientifically called as ‘Cyprinidae’) in Sri Lanka.

The team of researchers have combed a sampling of 90 sites across Sri Lanka to identify the new species. The team consisting of Hiranya Sudasinghe of Evolutionary Ecology and Systematics Lab, Department of Molecular Biology and Biotechnology, University of Peradeniya, Rohan Pethiyagoda of Ichthyology Section, Australian Museum, Sydney, NSW, Australia, Ranasinghe Hettiarachchige Tharindu Ranasinghe of Butterfly Conservation Society of Sri Lanka, Malwana, Rajeev Raghavan of Department of Fisheries Resource Management, Kerala University of Fisheries and Ocean Studies (KUFOS), Kochi, India, Neelesh Dahanukar of Indian Institute of Science Education and Research (IISER), Pune, India and Madhava Meegaskumbura of Guangxi Key Laboratory of Forest Ecology & Conservation, College of Forestry, Guangxi University, Nanning, China.

Sudasinghe told The Sunday Island that more extensive sampling of Rasbora in India, and analysis based on multiple markers may reveal “a more complex phylogenetic topology” (diversity).

“The Sri Lankan diversification derives from a common ancestor which arrived from India during a sea-level low-stand in the mid-Miocene (15.1 Ma [95% HPD: 11.5–19.8 Ma]), when the present-day island was sub aerially connected to the Indian subcontinent by a broad isthmus”, he added.

Rasbora is generally believed to have arrived in the island from the Indian sub-continent centuries ago when Sri Lanka stood geographically merged with India.  In the latest study, researchers confirm this belief.

“Our analysis suggest that Sri Lankan Rasbora derive from a Mid Miocene, India to Sri Lanka dispersal”, he noted, and added that Sri Lankan Rasbora diversity is higher than that of the Indian peninsula.

The Sri Lankan diversity of Rasbora provides an opportunity to understand the evolutionary and phylogenetic relationships of freshwater fishes in the island. Understanding the bio geography, phylogenetic and the evolutionary relationships of species are pivotal in formulating effective assessments of the conservation status of species as well as to draw up species conservation management plans.

However, such studies are still at very early stages when it comes to the freshwater fishes in Sri Lanka.

The first-ever molecular phylogeny of Sri Lankan Rasbora and reassess the taxonomic identities of the five species of Sri Lankan Rasbora based on an island-wide survey. In this study, based on molecular, morphological and statistical analyses using finer geographic sampling, validate the five putative species of Rasbora previously recognized in Sri Lanka.

In addition, a new species of Rasbora was discovered from eastern Sri Lanka. This new species was named Rasbora adisi. The species name “adisi” means mysterious or enigmatic in Sinhala: an allusion to the cryptic nature of this species.

The new species is found in eastern basins in Sri Lanka such as Gal Oya, Menik River and Kumbukkan River and show the closest resemblance to Rasbora naggsi. However, the new species is different from R. naggsi by a combination of morphological characters in addition to been genetically distinct.

 

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EC member Hoole moves SC against 20A

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Petitions challenging 20A before five-judge bench of SC today 

By Chitra Weerarathne

Petitions filed in the Supreme Court, challenging the constitutionality of the proposed 20th Amendment to the Constitution of Sri Lanka, will be called before a five-judge bench today.

These petitions have said that people’s approval at a referendum as well as a two-thirds majority in Parliament will be needed to enact the Bill.

All the petitions have basically said that the Bill has a section, which says a dual citizen can contest to enter the Parliament of Sri Lanka and run for President threatened national security.

The petitions challenge the powers vested in the President. The President could sack the Prime Minister and the Ministers. Once the Bill becomes law, fundamental rights petitions could not be filed to challenge an act of the President, the petitions have pointed out.

The investigating powers of the Auditor General have been curtailed. The powers vested in the Elections Commission when an election is on is also limited, the petitioners have argued.

The petitions have requested the Supreme Court to declare that a two-thirds majority in Parliament and people’s approval at a referendum will be needed to enact the proposed amendment.

Among the petitioners are Elections Commission member Ratnajeevan Hoole, the Samagi Jana Balavegaya, Attorney-at-Law Indika Gallage, Mayantha Dissanayake, S. J. B. Member of Parliament for the Kandy District and also the President of the Youth League of the Samagi Jana Balavegaya.

The Supreme Court bench will comprise the Chief Justice Jayantha Jayasuriya, Justice Buwaneka Aluwihare, Justice Sisira de Abrew, Justice S. Thurairajah and Justice Vijith K. Malalgoda.

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Senasinghe announces quitting politics

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By Akitha Perera

Former non-cabinet minister of the yahapalana government Sujeewa Senasinghe announced yesterday that he would quit politics. 

He had also stepped down as the SJB Deputy Secretary, Senasinghe said. 

Senasinghe said that he intended to focus on his business in the future and that he would commence work on his PhD from January 2021. 

He unsuccessfully contested the Aug 05 general election from the Colombo district on SJB ticket.

Senasinghe commenced his political career as a member of the Western Provincial Council of the UNP. He was elected to Parliament twice from the same party. 

He earned notoriety by publishing a book denying the bond scam ever took place.

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Pujith insists his hands were tied during crucial period 

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By Rathindra Kuruwita

He had been aware that the activities and preaching of Islamists would have an impact on reconciliation, but those in higher positions were convinced otherwise, former IGP Pujith Jayasundara, yesterday, told the Presidential Commission of Inquiry (PCoI) investigating the Easter Sunday attacks.

The ex-IGP said that although he too had received information about activities of Islamic extremists by late 2018, he had been barred from the National Security Council (NSC) by then.

“I couldn’t share the information I had and I didn’t know what was discussed there. I couldn’t even assign a senior officer to represent me there.”

Jayasundara added that after he had received, on April 09, a report from State Intelligence Service (SIS) Director Nilantha Jayawardena about a possible terrorist attack, he forwarded the report to SDIG of Western Province, Nandana Munasinghe, SDIG crimes and STF M.R. Latheef, DIG special protection range Priyalal Dasanayake and Director of the Terrorism Investigation Division, Waruna Jayasundara and spoke to them over the phone.

Jayasundara said that he had also phoned all SDIGs in charge of provinces. The witness added that he had wanted to ensure that there would not be a leak, causing unnecessary problems in society.

“For example, the letter I sent to the Special Protection Range (SPR) was leaked to the media after the attacks.”

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