Kerala forests home to new spider species

Aathira Perinchery, Kochi
The Hindu, Arpil 6 2019

A group of jumping spiders that mostly occur in Eurasia and Africa, has been spotted for the first time in Ernakulam’s Illithodu forests by arachnologists from Kochi’s Sacred Heart College, Thevara. The team also found that the spider belonging to the genus (a taxonomic classification above species) Habrocestum is a species new to science.
The team came across the different-looking spiders — six of them, predominantly brownish-black in colour with white and creamy-yellow patches — while conducting a routine survey (funded by the Department of Science and Technology-Science and Engineering Research Board) for ground-dwelling spiders in the Illithodu reserve forests of the Malayatoor forest division, barely 60 km from here. Back in their laboratory, they examined the physical features of males and females. They also compared these to similar-looking spider specimens collected earlier from the Thattekkad Bird Sanctuary.
A detailed examination of the spiders’ physical features revealed that they belong to the genus Habrocestum that has been recorded mostly in Eurasia and Africa and never in India, till now. Comparisons with studies of European Habrocestum spiders revealed that the spiders from Illithode are a new species altogether, for they had distinctly different reproductive organs.
The spider also has a single long spine on the underside of both its first legs, and this gave it its scientific name Habrocestum longispinum (after Latin ‘longe’ meaning long and ‘spinae’ for spine). “It measures just around 2 mm and seems to prefer dry habitats, dwelling in forest litter,” said Mathew M. Joseph, assistant professor at Sacred Heart College and a co-author of the study published in the Journal of Natural History last month.
While more detailed ecological studies are required, threats could include unregulated tourism activities and even climate change (which could affect the small insects by altering the specific micro-climates that they prefer), he said.
The study extends the range of these spiders to India. The discovery also lends support to the continental drift theory that suggests that the world’s continents were one large, contiguous landmass where these creatures thrived many millions of years ago, added Dr. Joseph.

Read more »

Kerala is home to two new plant species

Aathira Perinchery, Kochi
The Hindu, April 3, 2019

A small ironwood tree that bears clumps of white flowers on its stalks, and a new species of wild fern are the latest additions to Kerala’s flora.
Researchers at the University of Calicut’s Department of Botany discovered the new species of ironwood, Memecylon idukkianum, from the borders of a shola forest (a high-altitude evergreen forest) in Idukki’s Mathikettan Shola National Park during a three-year plant survey there.
The discovery, published in the international peer-reviewed journal Kew Bulletin (the official journal of the United Kingdom's Royal Botanic Gardens) last month, details the features of the plant and where it grows.
The plant, that grows to the size of a small tree, can be identified apart from other Memecylon species by its pure white stalk-less flowers borne on its stalks during February and March, said research scholar S. Syam Radh, who discovered the plant along with Santhosh Nampy (Head, Department of Botany, University of Calicut).
Currently, the plant is known only from within the Mathikettan Shola National Park and its immediate environs.

Eight locations

The researchers found the plant growing in only eight locations here, some of which are vulnerable to anthropogenic activities.
Due to these potential threats as well as its rarity, the team suggests that the species be categorised as ‘Near Threatened’ based on criteria listed in the International Union for the Conservation of Nature and Natural Resources.
However, the other plant discovered recently, the wild fern Pteris subiriana, is found not just in Kerala but also Tamil Nadu and Maharashtra.
A team including researchers from Kolkata’s Botanical Survey of India first collected the fern from Mahabaleshwar in Maharashtra and then compared those plants with existing herbarium specimens of similar ferns species in several plant collections.
Using a scanning electron microscope, they studied the arrangement of the ferns' spores (small globules located under fern leaves through which ferns reproduce).
This showed that these ferns — which grow near waterfalls — are a new species, according to their study published in the international journal Phytotaxa.

Mushroom species

Another team from the University of Calicut has also described a new species of mushroom from Kerala, based on detailed studies of its physical features and by using genetic methods as well.
The new species Laccaria violaceotincta is currently known only from the single area it has been collected from by the team: the threatened myristica swamps of Kulathupuzha in Kollam district.

Read more »

Post-floods, Vazhachal’s winged species hit a low

Aathira Perinchery, Kochi
The Hindu, February 22, 2019

The results of a two-day survey in Vazhachal’s riverine stretches, including areas affected by last year’s floods, seem disquieting. It records a ‘low’ abundance of some insect taxa – butterflies and odonates (damsel and dragonflies) – as well as birds, especially along the Chalakudy river.
But with no similar surveys for comparison, do these results portray the actual impacts of the flood?
On February 9 and 10, volunteers – both amateurs and experts in species identification – from across the State recorded bird, butterfly and odonate species diversity and counted their numbers in 20 locations along the Chalakudy river and its streams. This revealed 196 bird species (including the great hornbill), 131 butterfly and 51 odonate species.
Though this shows “high” species diversity, the counts of all these taxa were lesser in flood-affected areas such as the Chalakudy river and higher in smaller streams not affected by the flood, claimed K.H. Amitha Bachan, an assistant professor, who supervised the survey, which was supported by the Kerala State Biodiversity Board and conducted by the Vazhachal Forest Department, the Western Ghats Hornbill Foundation and the Botany Research Department of MES Asmabi College, Kodungalloor.
“The flood damaged about 70% of the riverbank,” he said. “Areas immediately downstream of dams were most affected.”

Tell-tale changes

However, volunteers noted only tell-tale changes such as fallen trees and sand deposits which may not sufficiently capture the changes in the habitat. There is also no similar survey of the area, as well as its birds and odonates – especially abundances – before the flood to make comparisons.
But comparisons can be made, insisted Mr. Bachan, adding that small islands in the river disappeared due to the flood, as did existing mudbanks and sandbars. While new sandbanks appeared in some areas, the depths of pools in others decreased due to the silt deposition. Such alteration and loss of habitat could have caused the lower numbers of odonates, which are very dependent on specific aquatic microhabitats for survival, he said.
The flood would indeed have affected the habitat and its denizens, but without previous data for comparison it would not be useful, commented a scientist independent of the survey.
Rejuvenating ancient riparian forests would not be easy, but a project to initiate a tree nursery and plant riparian saplings in appropriate areas during the monsoon has been mooted, said Divisional Forest Officer of Vazhachal, S.V. Vinod.

Read more »

Blink and miss: Kerala’s mystery frog

Aathira Perinchery, Kochi
The Hindu, February 14, 2019

Forget dense forests. Even roadsides could be harbouring new species that are hard to find. Scientists from the University of Delhi have discovered a new amphibian — a mysterious narrow-mouthed frog, that makes only a four-day appearance in seasonal roadside puddles every year in Kerala’s Wayanad district — according to their study published on Wednesday in Scientific Reports.
The frog Mysticellus franki (named after evolutionary biologist Franky Bossuyt from Brussel’s Vrije Universiteit) is not just a new species but also belongs to a completely new genus, Mysticellus (after Latin mysticus, meaning mysterious; and ellus, meaning diminutive, for the frog is just around 3 cm long).
Sonali Garg, a doctoral researcher at the University of Delhi, first found tadpoles of the species — whose physical features and DNA did not match any known species — during routine field surveys in Wayanad district in 2013. After a long search, the team finally found large groups of around 200 adult frogs in 2015 in a single locality in Wayanad, just metres away from vehicular movement, plantation activities and human settlements.
After breeding for four days, the frogs mysteriously disappeared from the spot; a habit that earned the tiny amphibians their name. Back in the laboratory, Ms. Garg and her supervisor S.D. Biju studied multiple aspects of the species — including physical characteristics of adults and larvae, DNA and calls of adult males that they recorded on field — in detail.
Physical features (such as its marble-patterned underside) and DNA studies revealed the frogs to be a completely new species. Adults have two black spots that look like eyes on their backs, a defensive feature.
‘Genetic studies further revealed that the frog is around 40 million years old and its nearest relatives live more than 2,000 km away, in southeast Asia (including Indo-Burma, Malaysia and Vietnam). This southeast Asian connection adds strength to the theories that India and southeast Asia were connected in the past by land bridges, suggest the authors.

Read more »

Presence of invasive mussel confirmed in Kochi backwaters

Aathira Perinchery, Kochi
The Hindu, January 03, 2019  

From clambering lantana plants to karimeen-like red-bellied paku, invasive species come in all sizes. The latest addition to Kerala’s invasives list is only around a centimetre or two long: scientists have confirmed the presence of the invasive black-striped mussel Mytilopsis sallei in Kochi’s backwaters.

'Alien' mussel

In a study published on December 25 in the scientific journal Current Science, researchers at the Cochin University of Science and Technology (Cusat) used basic genetic methods to confirm the identity of mussels they collected from Cochin harbour and Ezhupunna in Alappuzha. They extracted DNA from these mussels. While running this through an international online database, they matched it to the DNA of mussels observed from the Lam Tsuen River in Hong Kong (China), confirming that it is the same species that is now found in Kochi’s backwaters.
The black-striped mussell, native to the South and Central Americas, is an invasive species in most parts of the world and has been recorded from countries including Hong Kong, Australia and Japan. In India, it has been recorded from the ports of Mumbai (Maharashtra) and Vishakapatnam (Andhra Pradesh). It spreads primarily through the discharge of ballast waters of ships (seawater carried in the ballast tanks of ships to improve its stability and balance). The fast-growing species – which dwells in shallow water – can tolerate a wide variety of environmental conditions (salinity, water temperatures and oxygen levels; tests in the laboratory confirmed this again), which helps them thrive in the new areas they colonise.
The researchers estimate that one square metre near Fort Kochi (from where they collected some of the mussel samples) contains as many as 748 individuals. This is extremely high, said Dr. Bijoy Nandan, professor at Cusat’s Department of Marine Biology and one of the scientists who conducted the study.

Several costs

Though tiny, these invasive mussels are ‘biofoulers’, he added: organisms that accumulate on wet surfaces, causing huge ecological and economic losses. They can cause the deterioration of coastal infrastructure; the Australian government, for instance, spent approximately US$ 2.2 million to eradicate Mytilopsis mussels from Darwin Harbour. The mussels can also displace native species of clams (which local fishermen depend on for their livelihood) from their coastal habitats and cause a reduction in native biodiversity. Now the mussels can be spotted along most of Kerala’s coastline, added Dr. Nandan.
“We do not know what other problems could occur if these black-striped mussels proliferate,” said Dr. Nandan. “Or if changing climates could be enhancing their survival in any way. Our molluscan resources are extremely under-studied and we need more research to address these gaps.”
If their numbers grow, harvesting the mussels for use as poultry feed or manure could be a possible management tool, he said.

 

Read more »

Exotic trees eating up Western Ghat’s grasslands

Aathira Perinchery, Kochi
The Hindu, January 3, 2019

The new year heralds bad news for the high-altitude grasslands of the Western Ghats. Over four decades, the country lost almost one-fourth of these grasslands and exotic invasive trees are primarily to blame, find scientists. Though grassland afforestation using pine, acacia and eucalyptus ceased in 1996, the exotics still invade these ecosystems, confirms a study published on January 2 in the international journal Biological Conservation.
When satellite images revealed to a team including scientists from the Indian Institute of Science Education and Research (IISER, Tirupati) grassland loss in Tamil Nadu’s Palani hills in early 2018, they decided to study how shola-grasslands (characterised by patches of stunted evergreen shola trees in the valleys and grasslands on hill slopes) across the Ghats – from the Baba Budan Hills in Karnataka to Tamil Nadu's Ashambu Hills – changed in extent between 1972 and 2017. The satellite images they accessed reveal that 60% of the shola-grassland landscape has changed; almost 40% (516 km2) of native high-elevation grasslands have disappeared.
Most of this loss occurred on the mountain tops of the Nilgiri, Palani and Anamalai hill ranges, which comprise more than half of the Ghat’s shola-grassland ecosystems, primarily due to the expansion of exotic trees (pine, acacia and eucalyptus). Even though no plantations were established between 2003 and 2017, invasion by existing trees increased areas under exotic plantations by 27% in the Palanis and 17% in the Nilgiris. Broadly, shola-grassland ecosystems in Tamil Nadu showed the highest rates of invasion. The researchers also visited 840 locations across the Ghats to confirm these changes. Despite this, there’s some good news: shola forests have remained “relatively unchanged” over these years. The Anamalai-Munnar areas have also remained stable during this time.

‘Little research focus’

However, all possible efforts must be made to conserve the remaining grassland tracts, said scientist Dr. Robin V. Vijayan (IISER Tirupati), one of the authors who led the study. “There is very little research focus on grasslands and mechanisms to restore them are also few, unlike forests,” he added.
“The immediate reaction would be to remove all exotics including mature plantations from grasslands but that should not be done,” said Godwin Vasanth Bosco, who has restored some grassland patches in Udhagamandalam.

Read more »