NEW BAT SPECIES DISCOVERED IN SL

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They most often go unnoticed because they are nocturnal and blend with the darkness. To some they are of no interest but to others they are of prime importance as they are a vital part of the environment. Not many of us pay attention to bats. But to scientists and researchers’ bats are of prime concern as they are important pollinators. 

It is not very often that we come across bats. But a local and foreign research team led by a young biologist Tharaka Kusuminda, engaged in bat studies in Sri Lanka, has managed to discover a new bat species living in Sri Lanka and India. This bat is scientifically known as Miniopterus phillipsi, and Phillip’s long-fingered bat in English.

This is the first time that a new species of Miniopterus bat has been discovered in the country and India after eight decades. It is also the first time that a new bat species of this genus has been discovered in Asia after six decades. Animal specimens related to this new species of bat have been found from Sri Lanka and India before, but they have been identified as a different species of bat.

Faculty of Agriculture, University of Ruhuna, and Corresponding author Kusuminda, Faculty of Agriculture, University of Ruhuna, Amani Mannakkara, Faculty of Applied Sciences, Rajarata University, Kanishka D. B. Ukuwela, Zoological Museum of M.V. Lomonosov Moscow State University, Russia, Sergei V. Kruskop, Deraniyagala, Chamara J. Amarasinghe, Zoological Survey of India, North Eastern Regional Centre, India, Uttam Saikia, Bat Conservation Trust, UK, Parvathy Venugopal, Sandaraja Wana Arana, Mathisha Karunarathna, Tea Research Institute, Rajika Gamage, Department of Vertebrates, Natural History Museum of Geneva, Switzerland and Department of Genetics and Evolution, University of Geneva, Switzerland Manuel Ruedi, Department of Zoology, Hungarian Natural History Museum, Hungary Gábor Csorba, Faculty of Science, University of Colombo, Wipula B. Yapa, and Negaunee Integrative Research Center, Field Museum of Natural History, USA Prof Bruce D. Patterson have contributed to this study.

Mistakenly identified

The morphological and genetic data of this species of bat has been used for this research, which was conducted under the initiative of Kusuminda. There they have discovered that previously these bats were mistakenly identified as the species Miniopterus fuliginosus. But the researchers point out that the species is spread only in the temperate climates of South Asia and the countries of the Southeast Asian region.

This is the second time that genetic technology has been used to confirm the taxonomic status of a bat species in Sri Lanka. But it is very sad that the use of this technology scarcely has been the main reason why the real species diversity of bats living in our country has not been properly revealed for decades, according to the researchers.

“This species of bat is named in honour of an English Scientist, W.W.A. Phillips. Animal specimens collected from several places in Sri Lanka and a large number of animal specimens deposited in various museums of the world have been used for this research. Specimens of this new species have been found near the Bio Tea Garden Tea Estate located in Idalgashinna area and additional specimens have been found in Aranayak Sandaraja Forest, Thalawakele, Wellawaya Vaul Galge cave and the Wavulpane limestone Cave,” the Researchers said.

This species of bat shows a general distribution in the wet and intermediate environmental zones in our country they say and has been reported in several places in the dry zone. “But this species of bats choose only rock caves and much similar places as their day roosts, which is a matter of more concern in their conservation activities. The destruction of ecosystems in the guise of informal development projects in our country is a major threat to them and the destruction of large rocks that provide them with habitats for the need of granite stones will directly affect the future survival of this bat species,” the Researchers said.

Last bat species in 1932

They added that the last new species of bat introduced to the world from our country was in 1932 by W.W.A. Phillips. “After that three bat species were reported from Sri Lanka. But in those three cases, it has only been confirmed as the range extension of these three species into our country. Therefore, this new discovery can be considered as the first time a new species of bat is described from Sri Lanka to the world after 90 years. This research findings have recently been published in the latest issue of Acta Chiropterologica, a world-renowned scientific journal,” the Researchers explained.

The Old World bat genus Miniopterus Bona – parte, 1837, the sole representative of the family Miniopteridae, is characterised by remarkably conservative morphology and is considered as a monophyletic assemblage containing many cryptic species. As recently as 2005, the genus was thought to contain 19 species distributed over much of the Eastern Hemisphere. However, recent descriptions has more than doubled that number, and additional putative species await confirmation.

“Besides the genus Murina (which increased from 17 to 40 species since 2005), no other species bat genus has seen such a proportionate increase in numbers of species over this period, underscoring the cryptic nature of speciation in the genus Miniopterus. Genetic surveys have greatly aided the discovery of cryptic species in Miniopterus, especially among Afrotropical and Malagasy forms,” the Researchers said.

New species in eight decades

They say the genus Miniopterus is a monophyletic assemblage of many species characterized by remarkably conservative morphology. “The number of recognised species has more than doubled over the last two decades, mainly with newly recognised Afrotropical and Malagasy species. The newly described species is easily distinguished by its external and cranial dimensions from its smaller (M. pusillus) and larger
(M. magnater) congeners in India and Sri Lanka. This is the first description of a new Miniopterus species from Asia in six decades and from India and Sri Lanka in eight decades,” the Researchers said.

Their study highlights the importance of using both genetic and morphometric analyses in taxonomic studies on South Asian bats. “However, less attention has been paid to Asian forms, and for a long time, many larger Miniopterus from this continent were recognised as various subspecies of M. schreibersii. This essentially Mediterranean species is now considered to be endemic to the Western Palaearctic and does not range east beyond the Caucasus. In India and Sri Lanka, three distinctively sized species of Miniopterus are currently recognised: the small M. pusillus Dobson, 1876; medium-sized M. fuliginosus and large M. magnater Sanborn, 1931,” the Researchers explained.

The research paper states that the Asian bent-winged bat, M. fuliginosus was described from central Nepal by B. H. Hodgson in 1835 and was long considered a subspecies of M. schreibersii. “However, molecular phylogenetic studies established M. fuliginosus as a distinct species, confirming an earlier comprehensive morphological review. Miniopterus fuliginosus is thought to range from northeastern Afghanistan and northern Pakistan, through India, Nepal, Sri Lanka, northern Myanmar, northern Vietnam, southern and eastern China, to Taiwan, Korean Peninsula, easternmost Russia, and Japan,” the research paper states.

Surveys conducted in tea plantations

“However, variation of M. fuliginosus across its range remains poorly studied, especially in South Asian countries. Populations in central and southern India and Sri Lanka appear geographically isolated from the rest of the species range. We sought to critically compare Miniopterus populations from southern India and Sri Lanka with typical M. fuliginosus in both molecular and morphological terms,” the Researchers said.

Mitochondrial DNA sequences were used by the researchers to assess the phylogenetic relationships of Indian and Sri Lankan Miniopterus species. “Our findings show that Miniopterus populations in Peninsular India and Sri Lanka do not represent M. fuliginosus but differ from that species both genetically and morphologically. We describe it here as a species new to science. The Sri Lankan specimens newly reported in this study were collected during systematic surveys conducted from 2016 to 2020 in tea plantations and adjacent habitats of the wet zone of Sri Lanka,” the Researchers explained.

They surveyed 18 sites over an elevational range of 36–1673 m a.s.l. in Sri Lanka. Bats were captured in and around tea plantations and inside bat roosting sites using mist nets, harp trap, and hand nets. The triple-high mist net system was opened from sunset to midnight and monitored continuously.  Echolocation calls were recorded from three bats captured at the type locality and subsequently released. Recordings were taken from individuals flying in a closed room,” the Researchers said.

By Risidra Mendis