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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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MP’s wife, father-in-law among three detained

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Rishad held under PTA to be questioned

16-year-old girl’s death:

By Shamindra Ferdinando

Police investigating the death of 16-year-old Ishalini, the domestic servant at All Ceylon Makkal Congress (ACMC) leader Rishad Bathiudeen’s Baudhaloka Mawatha residence have arrested Ayesha Shiabdeen, 46, the wife of the former minister.

Police also took into custody Rishad’s father-in-law Mohammed Shiabdeen, 70, and Ponnaiah Pandaram alias Shankar, 64, a resident of Dayagama.

Police Spokesman Senior DIG Ajith Rohana said that Shankar had brought Ilashini from Dayagama to the Baudhaloka Mawatha residence of Samagi Jana Balavegaya (SJB) Vanni District lawmaker late last year.

Having studied the post postmortem report, they were taken into custody in terms of Section 360 C and Section 308 B of the Penal Code that dealt with human trafficking and cruelty to children, the top police officer said. According to him, so far 20 statements had been recorded.

Asked whether MP Bathiudeen, too, had been among the questioned, Senior DIG Rohana said the parliamentarian detained under the Prevention of Terrorism Act (PTA) over 2019 Easter Sunday carnage, too, would be interrogated in that regard.

The ACMC contested the last general election on the SJB ticket. It switched its allegiance to the SJB ahead of 2020 general election after having represented the cabinet in UNP led yahapalana administration. Rishad has also served President Mahinda Rajapaksa’s cabinet during his second term.

Having suffered serious burn injuries on July 3 at the MP’s residence and admitted to the National Hospital, Illashini succumbed to her injuries on July 15th. Medical examination revealed that she had been raped over a period of time.

The police spokesman said that they intended to secure court approval to detain the suspects for 72 hours. A Superintendent of Police could obtain such approval on the strength of a B report submitted to the court in respect of offenses on children.

Although, the police indicated earlier in the day they would be produced in Colombo Magistrate court they weren’t brought in.

Meanwhile, the SJB said that interested parties were making a despicable attempt to politicize the incident. The police should be allowed to conduct the investigation without interference, a spokesman for the main Opposition party said.

 

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Women’s organisations in North conduct protests demanding justice for Ilashini

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A section of those engaged in Jaffna protests

 

By Dinasena Ratugamage

Women’s organisations in the North yesterday held a number of demonstrations in Vavuniya, Mannar, Kilinochchi and Jaffna against the death of J. Ilashini, the 16 -year-old girl who died while working at SJB MP Rishad Bathiudeen’s residence.

The protesters urged authorities to ensure that investigations into the death are conducted in a transparent manner. The family of the victim should be compensated and those guilty punished, they said.

Representatives of the organisations said that if justice was not done, they would hold a massive demonstration in Tarapuram, Mannar, which Bathiudeen represents in Parliament.

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Dancer lodges complaint with police over FB post 

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Police headquarters yesterday (23) said that dancer Anusha Damayanthi had lodged a complaint with the Criminal Investigation Department (CID) over a Facebook post alleging that she was running a brothel.

Police headquarters said that Damayanthi, while denying the accusation, had also brought to the CID’s notice that a minister was being accused of lambasting the Walana anti-crime strike force for carrying out the raid. Police said that an investigation was underway.

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