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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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Judicial vacancies: President keeps country guessing

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President

The NPP government has not taken a final decision regarding filling of the vacancies in the judiciary.

A group of Opposition MPs, led by SJB leader Sajith Premadasa, on 12 June, requested Speaker Dr. Jagath Wickremeratne to take up the issue of judicial vacancies with President Dissanayake. Opposition sources said that there were four vacancies, each in the Court of Appeal and the Supreme Court, and the inordinate delay had adversely affected the judiciary.

Government sources indicated that there was no change in the status quo as regards filling of vacancies. Referring to the government proposal to extend the retirement age of judges, authoritative sources said that no final decision had been taken yet.

SJB lawmaker Dayasiri Jayasekera told The Island that they would raise the issue in Parliament this week.

He said that the deliberate delay in making appointments to superior courts and the move to extend the retirement age couldn’t be taken separately.

The MP noted that the Bar Association of Sri Lanka, the Lawyers’ Collective, the Colombo High Court Lawyers’ Association, Colombo Magistrate’s Court Lawyers’ Association and the Bar Association of Badulla had opposed the government move.

There hadn’t been any public statements in support of the government move, MP Jayasekera said, urging the government to end uncertainty in the judiciary.

by Shamindra Ferdinando

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Sajith calls on Opposition parties to rally around SJB

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Sajith

SJB leader Sajith Premadasa has invited the UNP and other political parties to join his party. Premadasa, who is also the leader of the Opposition, has emphasised that the UNP and the SJB could reach a consensus on policies but his party wouldn’t, under any circumstances, accept whatever formula to share positions. Premadasa said so, speaking to the media over the weekend, after meeting the Mahanayaka Thera of the Malwatta Chapter of the Siyam Nikaya Most Venerable Thibbatuwawe Sri Siddhartha Sumangala Thera.

A statement issued by the Opposition Leader’s Office quoted MP Premadasa as having extended an invitation to all political parties to give up extremist policies and join the SJB.

The SJB leader alleged that the NPP government feared facing elections and that was the reason for the inordinate delay in holding Provincial Council polls. PC polls were last held in 2012, 2013 and 2014, on a staggered basis. Premadasa said that if PC polls were held his party would definitely win the majority of PCs.Premadasa also urged the government to reduce electricity tariffs and fuel prices.

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Ex-EC Chief slams govt. over PC polls delay

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Deshapriya

Former Chairman of the Election Commission, Mahinda Deshapriya, on Saturday, strongly criticised the continued postponement of local government elections, declaring that every day without elections constitutes a violation of both the Constitution and democratic principles.

Speaking during an interview with journalist Bhanuka Rajapaksa, on Hiru TV, on Saturday, Deshapriya described the current administration of local government institutions by unelected officials as fundamentally undemocratic and contrary to the spirit of representative governance.

Deshapriya said local authorities, across the country, are presently being managed by secretaries and bureaucrats rather than elected representatives, depriving citizens of their democratic right to be governed by individuals, chosen through the electoral process.

“If the Constitution recognises and provides for local government institutions, then it is the responsibility of the State to ensure that elections are held and that these bodies are administered by representatives, elected by the people,” he said.

Deshapriya rejected attempts to justify the prolonged delay, arguing that responsibility for the situation rests with the government.

He noted that while various political parties have publicly stated their readiness to face elections, the ruling administration possesses the authority to resolve any issues relating to the electoral system.

The former Election Commission chief pointed out that the government enjoyed a two-thirds majority in Parliament, enabling it to enact any legislative amendments required to facilitate the conduct of elections. Instead, he said, successive committees and review processes had been used to postpone a final decision.

He also referred to efforts by opposition legislators who have moved motions seeking to address concerns relating to the electoral framework and expedite the holding of local government polls.

Deshapriya warned that any attempt to appoint a fresh delimitation committee could further delay the electoral process, making it unlikely that local government elections would be held within the current year.

He also dismissed claims that financial constraints have prevented the conduct of elections. Expressing surprise at such assertions, he questioned how funding shortages could be cited as a reason for postponement while expenditure continues in other sectors.

According to Deshapriya, the existence of laws establishing local government institutions imposes an obligation on the State to ensure that those institutions are populated through democratic means.

“The legal framework exists. If elected representatives are not appointed through elections and institutions continue to function under unelected administrators, that is a failure of the State,” he said.

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