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04/11/2025

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CA-04/11/2025

Two new species of marine amphipods, Grandidierella geetanjalae and Grandidierella khambhatensis, have been found by a team of researchers from Chilika and the Gulf of Khambhat, recently.

About Amphipods
Amphipods are an order of small crustaceans found in virtually all aquatic and some humid terrestrial environments worldwide. They are a diverse group, with over 10,700 recognized species, and are commonly known as scuds, sideswimmers, beach fleas, or sand hoppers. 

Key Characteristics

• Body Structure: Amphipods typically have a laterally compressed body, giving them a "C" shaped or humped-back appearance. They lack a carapace (the hard upper shell found on crabs and lobsters).
• Appendages: The name "Amphipoda" means "different feet," which refers to their specialized legs. They have several types of legs for different functions, including claw-like gnathopods for feeding and grasping, and pleopods and uropods for swimming, jumping, or burrowing.
• Eyes: Most species have sessile compound eyes that are flat on the head and lack eyestalks, although many subterranean and deep-sea species are eyeless.
• Size: Most amphipods are small, typically a few millimeters to a couple of centimeters long. However, deep-sea species can be much larger, with some specimens reaching up to 34 centimeters (13 inches) in length. 

Habitat and Diet
Amphipods are found from the deepest ocean trenches to high-altitude lakes and even damp leaf litter on land. 

• Habitat Diversity: While most species are marine, a significant number inhabit freshwater and brackish environments. Terrestrial species require humid environments because they lack the waxy exoskeleton layer that prevents desiccation.
• Diet: They exhibit diverse feeding strategies and are often detritivores or scavengers, consuming dead and decaying plant and animal matter. Some are herbivores that graze on algae, while others are omnivores or predators of smaller invertebrates. 

Ecological Importance
Amphipods play a vital role in ecosystems as a key link in the food web. 

• Nutrient Cycling: As detritivores, they are crucial to the decomposition of organic material, which helps recycle nutrients back into the environment.
• Food Source: They are a primary food source for many organisms, including fish, waterfowl, and marine mammals like gray whales.
• Bioindicators: Their sensitivity to water quality and pollution makes them useful as bioindicators for assessing ecosystem health in scientific research. 

Types of Amphipods
The order Amphipoda is currently divided into six suborders, including: 

• Senticaudata: The largest suborder, which includes most freshwater and terrestrial species (e.g., landhoppers).
• Hyperiidea: Exclusively marine and planktonic amphipods, many of which live in association with gelatinous animals like jellyfish and salps.
• Cyamidae: Highly specialized parasitic amphipods known as whale lice, which attach themselves to marine mammals.
• Caprellidae: Also known as "skeleton shrimp," these have elongated bodies and cling to algae and other structures. 

About Grandidierella Geetanjali and Grandidierella Khambhatensis
Grandidierella geetanjalae and Grandidierella khambhatensis are two newly discovered species of small, shrimp-like marine amphipods. Both are detritivorous crustaceans, meaning they feed primarily on organic matter and contribute to natural ecosystem cleaning processes. 

Grandidierella geetanjalae

• Discovery Location: This species was collected from the Chilika lagoon (a brackish water lake) near Rambha in the Ganjam district of Odisha, on the east coast of India.
• Naming: It was named in honor of Geetanjali Dash, the vice-chancellor of Berhampur University.
• Distinguishing Feature: It differs from close congeners by having a comparatively smaller spine on the posterior margin of the carpus of gnathopod 1 (a type of leg modified for feeding/grasping).
• Size: Measures between 5.5 and 6 mm in length. 

Grandidierella khambhatensis
Discovery Location: This species was collected from the Gulf of Khambhat in Gujarat, on the west coast of India.

• Naming: It was named after its type locality, the Gulf of Khambhat.
• Distinguishing Feature: It differs from its close congener G. perlata by having a hook-shaped uropod 3 ramus (part of the tail structure).
• Size: Measures between 5.5 and 6 mm in length. 

General Information

• Both species were identified and described by a joint team of researchers from Berhampur University (Odisha) and Hemchandracharya North Gujarat University (Gujarat).
• Their discovery was published in the journal Zootaxa.
• The species in the Grandidierella genus generally inhabit marine, estuarine, and coastal waters and are known for their sexually dimorphic gnathopods (males have much larger first gnathopods than females). 

A team of researchers exploring biodiversity in the Western Ghats recently discovered a new species of spider named Pilia malenadu.

About Pilia malenadu
Pilia malenadu refers to a recently discovered new species of jumping spider found in the Western Ghats of Karnataka, India. It was named "malenadu" to credit the Malenadu region where it was found. 

• The Spider Species: Pilia malenadu
• Discovery: The species was discovered by a team of researchers in the Madhugundi village in the Mudigere taluk of Chikkamagaluru district, at the foothills of the Western Ghats.
• Genus: It belongs to the Pilia genus of jumping spiders, a genus that had not had a new species recorded in approximately 123 years.
• Significance: This discovery is significant not only due to the long gap since the last finding in this genus, but also because researchers found and documented both male and female spiders of the species for the first time.
• Habitat: The spiders were found concealed between the leaves of specific plant species, Memecylon umbellatum and Memecylon malabaricum, indicating the rich and healthy ecosystem of the region. 

The Malenadu Region
"Malenadu" (or Malnad) is a geographical region in Karnataka, India, that spans the eastern and western slopes of the Western Ghats. The name comes from the Kannada words "male" (mountain/rain) and "nadu" (land), literally meaning the "land of rain" or "mountainous land". 

Key features of the region:

• Geography: Characterized by rugged terrain, rolling hills, dense rainforests, and numerous rivers and waterfalls.
• Climate: The region receives heavy annual rainfall and has a humid, moderate climate throughout the year, with places like Agumbe recording among the highest rainfall in India.
• Biodiversity: It is a biodiversity hotspot, home to many endemic species of flora and fauna, including medicinal plants, the Lion-tailed macaque, and the Malabar civet.
• Culture & Economy: The area has a rich heritage with ancient temples and is known for agriculture, particularly arecanut, coffee, pepper, and cardamom plantations. 

Heavy metals are polluting the Cauvery River and its fish, researchers from Tamil Nadu have reported.

About Heavy Metals

• Heavy metals are a group of metallic elements with relatively high densities, atomic weights, or atomic numbers, often defined as having a density greater than 5 g/cm³.
• These elements include both naturally occurring metals and certain metalloids and are characterized by their toxic or poisonous nature at low concentrations.
• Some examples of heavy metals are lead, mercury, cadmium, arsenic, chromium, and bismuth.

Definitions and Characteristics

• Heavy metals are not always consistently defined: most definitions rely on criteria such as density, atomic number, or specific chemical behavior.
• They tend to be much less reactive compared to lighter metals and have fewer soluble sulfides and hydroxides.
• Many are rare in the Earth's crust but are widely used in industrial, agricultural, and domestic applications.

Environmental and Health Impacts

• Heavy metals such as chromium, arsenic, cadmium, mercury, and lead are major environmental hazards due to their toxicity and widespread use.
• These metals can interfere with enzymatic processes and are known to cause systemic toxicity, damaging the central nervous system, causing degenerative diseases, and acting as carcinogens (cancer-causing agents).
• Sources of environmental contamination include mining, industrial activities, agricultural runoff, and domestic and pharmaceutical waste.

Uses and Prevalence
Historically, heavy metals like iron, copper, and tin were used for tools and ornaments, while precious metals such as gold and platinum remain important economically.
Today, heavy metals are utilized in everything from electronics and vehicles to plastics and solar panels. Despite their utility, their misuse and accumulation pose significant risks to human health and ecological systems.
Key Examples

• Essential nutrients: Iron, cobalt, copper, and zinc (can be toxic in large amounts).
• Highly toxic: Mercury, lead, arsenic, cadmium (can cause neurological and systemic damage).
• Environmental sources: Mining, industrial production, agricultural runoff, and weathering.

Conclusion
Heavy metals, while vital in many industrial and biological functions, must be carefully managed because of their potential toxicity and environmental persistence. Modern concerns focus on contamination, exposure risks, and remediation strategies. The Pampadum Shola National Park which was once dominated by invasive Australian wattles is undergoing a remarkable transformation and its grasslands are being restored, reviving streams and native species.

About Pampadum Shola National Park
Pampadum Shola National Park  is the smallest national park in Kerala, renowned for its unique high-altitude shola-grassland ecosystem and significant biodiversity. Located in the Idukki district of the southern Western Ghats, the park plays a critical role as a watershed and wildlife corridor. 

Key Features

• Shola-Grassland Ecosystem: The park is a prime example of the shola-grassland mosaic, a unique montane ecosystem found only in the high ranges of the Southern Western Ghats.
• Watershed: The grasslands act as natural aquifers, capturing and slowly releasing rainwater into the headstreams of the Pambar and Vaigai rivers, which are vital for the plains of Tamil Nadu.
• Biodiversity Hotspot: Despite its small size (approximately 1.32 sq km), the park is a rich habitat for numerous endemic, rare, and endangered species of flora and fauna.
• Restoration efforts: The park has become a model for ecological restoration in India by successfully removing invasive Australian wattle trees, which had previously suppressed native flora and depleted water tables. 

Flora and Fauna
The park's diverse habitats support a wide range of life, including:

• Fauna: It is home to several important mammals like the Indian elephant, gaur (Indian bison), leopard, wild boar, sambar deer, and the highly elusive, endemic Nilgiri marten (the only marten species found in South India). It also has a rich bird population (e.g., Kerala laughing thrush, black-and-orange flycatcher, Nilgiri wood-pigeon) and over 100 species of butterflies.
• Flora: The vegetation includes 22 species of trees, 74 species of herbs and shrubs, and various rare medicinal plants and orchids. The native shola forests feature a stunted canopy of trees, moss-draped branches, and carpets of ferns. 

Recently, an autopsy report from the Indian Veterinary Research Institute revealed that a lone African elephant at the National Zoological Park in Delhi died due to the rare rodent-borne virus — encephalomyocarditis virus (EMCV).

Encephalomyocarditis Virus (EMCV) key points:

• EMCV is a small, non-enveloped, positive-sense single-stranded RNA virus belonging to the Cardiovirus genus and Picornaviridae family.
• It causes encephalomyocarditis, a disease involving myocarditis (heart inflammation), encephalitis (brain inflammation), neurological diseases, reproductive disorders, and diabetes in many mammalian species.
• Pigs are highly susceptible to EMCV and often develop acute myocarditis leading to sudden death; mortality can be very high in young piglets.
• The virus is also known to infect other mammals, including zoo animals like African elephants, and humans, although human infections are rare and usually asymptomatic.
• EMCV is transmitted primarily via contamination from feces or urine of infected rodents, which are considered the natural reservoir.
• Infected pigs show symptoms like fever, respiratory distress, sudden death, and reproductive failures such as abortions.
• Diagnosis depends on virus isolation, PCR assays, and immunohistochemical testing; single serum antibody tests are less reliable due to subclinical infections.
• There is no specific treatment; supportive care is given to manage symptoms and complications.
• EMCV is used as a model virus in immunology research, particularly in studying immune responses like Toll-like receptor signaling.
• The virus’s ability to evade host immune responses contributes to its virulence.
• EMCV has zoonotic potential, with human infections occurring mainly via fecal-oral routes, but severe human disease is rare.
• Pathological findings in animals include myocarditis with necrotic lesions in the heart, meningeal inflammation in the brain, pulmonary edema, and fluid accumulation in body cavities.
• Outbreaks in captive and wild animals have been reported globally, raising concerns especially in veterinary and conservation contexts.

Recently, the Union Minister for Development of North Eastern Region laid the foundation stone for the Integrated Sohra Circuit Development under the Prime Minister’s Development Initiative for North Eastern Region (PM-DevINE) scheme.

About Integrated Sohra Tourism Circuit
The Integrated Sohra Tourism Circuit is a major new initiative by the Ministry of DoNER and the Government of Meghalaya to transform Sohra (Cherrapunjee) into a sustainable, world-class, multi-day experiential eco-tourism hub. The foundation stone for the project, which involves a total investment exceeding ?650 crore (with over ?221 crore specifically under the PM-DevINE scheme), was recently laid on November 1, 2025, by Union Minister Jyotiraditya M. Scindia and Chief Minister Conrad K. Sangma. 

Key Objectives

• Transform Sohra: Shift Sohra from a short excursion destination to a multi-day immersive experience of global standards.
• Boost Local Economy: Generate significant direct and indirect employment opportunities (expected to be over 4,600 jobs) and increase tourist spending sixfold.
• Promote Sustainable Tourism: Implement a community-driven, eco-friendly, and climate-resilient tourism model that preserves the region's natural and cultural heritage.
• Enhance Infrastructure: Develop key tourist attractions and improve connectivity to the region. 

Project Components and Attractions
The circuit includes the development and enhancement of several key sites: 

• Sohra Experience Centre at Kutmadan: Serving as the cultural nucleus, this ?115 crore centre will feature amphitheatres, rain experience parks, art galleries, and craft pavilions showcasing Meghalaya's tribal heritage.
• Nohkalikai Falls Precinct Development: Enhancing visitor facilities at one of India's highest waterfalls.
• Mawsmai Eco Park Development: Promoting sustainable tourism and environmental awareness.
• Other Attractions: Development of the Seven Sisters Falls Viewpoint, Shella Riverside, Wah Kaba Falls, and Wahkaliar Canyon, which will include adventure tourism features like hot-air balloon rides.
• Connectivity: Improved road connectivity, including the Pynursla-Latangriwan-Mawlynnong Road providing all-weather access to Mawlynnong (Asia's cleanest village), and the upcoming Shillong-Silchar Greenfield Expressway nearby. 

Implementation
The project is funded under the Prime Minister's Development Initiative for North Eastern Region (PM-DevINE) scheme and is implemented through the Ministry of Development of North Eastern Region (MDoNER). Skill development programs for local youth in hospitality and safety management are also part of the initiative to ensure the local community benefits directly from the increased tourism.  The forest department is preparing to launch the next round of tiger census in the Nagarjuna Sagar Tiger Reserve (NSTR).

About Nagarjunasagar-Srisailam Tiger Reserve

• The Nagarjunasagar-Srisailam Tiger Reserve (NSTR) is India's largest tiger reserve, located in the Nallamala hill ranges, an offshoot of the Eastern Ghats, mainly in Andhra Pradesh.
• It was officially designated a tiger reserve in 1983 and covers an extensive area of about 3,728 square kilometers, including core and buffer zones.
• The reserve spreads across districts including Prakasam, Nandyal, and Palnadu in Andhra Pradesh and also parts of Telangana.
• NSTR is formed by two wildlife sanctuaries: the Rajiv Gandhi Wildlife Sanctuary and the Gundla Brahmeswaram Wildlife Sanctuary.
• The reserve features diverse terrain such as plateaus, ridges, gorges, and deep valleys with tropical dry deciduous forests that support rich biodiversity.
• The Krishna River runs through the reserve for about 270 kilometers, creating a vital water source for its flora and fauna.
• This tiger reserve is home to a significant population of Bengal tigers, along with leopards, sloth bears, Indian pangolins, wolves, and prey species like chinkara, blackbuck, spotted deer, and wild boar.
• It also hosts over 150 bird species and various reptiles.
• The area holds cultural and historical significance, housing ancient temples such as the Mallikarjuna Swamy Temple at Srisailam and archaeological sites including Buddhist relics and rock shelters.
• Historical remnants like forts belonging to ancient dynasties such as the Kakatiyas also dot the landscape.
• The Nallamala Hills within the reserve are known for waterfalls like the Ethipothala Falls and Gundam, making NSTR both an ecological hotspot and a place of cultural heritage.
• The reserve plays a critical role in India's tiger conservation under Project Tiger and continues to contribute to wildlife protection and biodiversity preservation in southern India.

Recently, concerns have been raised by doctors about melatonin supplements being taken by a large number of people with no medical supervision.

About Melatonin
Melatonin is a natural hormone produced by the brain's pineal gland primarily to regulate the sleep-wake cycle (circadian rhythm). It is also widely available as an over-the-counter dietary supplement, mainly used for short-term sleep issues like insomnia and jet lag. 

Natural Function
Circadian Rhythm Regulation: The pineal gland increases melatonin production in darkness, signaling the body to get ready for sleep by causing drowsiness and lowering body temperature. Exposure to light, especially blue light, decreases production, which helps the body stay awake.

• Other Roles: Beyond sleep, melatonin has antioxidant and anti-inflammatory properties that help protect cells from damage. It is also involved in immune function, mood regulation, and - in some animals - seasonal reproduction cycles.
• Natural Decline: The body's natural melatonin production tends to be highest in children and teens before puberty, and steadily declines with age, which can contribute to fragmented sleep patterns in older adults. 

Melatonin Supplements
Melatonin supplements are synthetic versions of the hormone used to add to the body's natural supply. 
Common Uses: 

• Jet lag: Helps reduce symptoms like daytime tiredness and disturbed sleep, especially after eastward travel across multiple time zones.
• Delayed sleep-wake phase disorder: Helps individuals (especially young adults and children) who have trouble falling asleep at conventional bedtimes fall asleep sooner.
• Short-term insomnia: May help some people fall asleep slightly faster.
• Anxiety before surgery: Can help reduce pre-operative anxiety in adults and children. 

Important Considerations and Risks

• Regulation: In the United States, melatonin is regulated as a dietary supplement, not a drug, meaning the products are not as strictly regulated by the FDA. Studies have found the actual melatonin content in supplements can vary widely from the amount listed on the label.
• Side Effects: Common side effects are generally mild and may include headache, dizziness, nausea, and daytime drowsiness.
• Interactions: Melatonin can interact with other medications, including blood thinners (anticoagulants), blood pressure medications, diabetes medications, and immunosuppressants.
• Specific Populations: Pregnant or breastfeeding women, and individuals with depression, bleeding disorders, or seizure disorders should consult a healthcare provider before use. Long-term effects, especially in children and adolescents, are not fully understood, and some concern exists that it may affect hormonal development. 

Recently, the Chief Minister of Odisha performed the groundbreaking ceremony for  the country’s first end-to-end silicon carbide semiconductor production plant.

About Silicon Carbide
Silicon carbide (SiC) is a synthetic, crystalline compound made from silicon and carbon, renowned for its extreme hardness and excellent thermal conductivity. It is widely used in industries due to its durability, high temperature resistance, and semiconducting properties.

Key Properties

• Hardness: Among the hardest materials, SiC only trails diamond, cubic boron nitride, and boron carbide. This makes it suitable as an abrasive, in machining, grinding wheels, and sandpapers.
• Thermal Conductivity & Stability: SiC exhibits superior thermal conductivity and low thermal expansion, ensuring dimensional and performance stability at high temperatures.
• Wear and Oxidation Resistance: Its chemical inertness provides resistance to wear and oxidation, ideal for protective applications like bulletproof vests and automotive components.
• Wide Bandgap Semiconductor: Its wide bandgap (3.26 eV) enables devices to operate at high voltages and temperatures, outpacing traditional silicon in power electronics.
• Appearance: Typically seen as a black-grey to green powder or as lustrous crystals.

Structure and Chemistry

• Crystallography: SiC crystallizes in close-packed structures with strong covalent bonds, and occurs as various polytypes—stacking arrangements of tetrahedra.
• Natural Occurrence: Rarely found as moissanite in meteorites, nearly all commercially used SiC is synthetic.

Uses and Applications

• Abrasives: Due to its hardness, SiC is a popular abrasive in machining and lapidary work.
• Automotive: Used in brake and clutch components for endurance under high-stress conditions.
• Bulletproof Armor: Plates made of SiC ceramics provide protection because of their high strength.
• Electronics: SiC substrates enable high-powered semiconductors, LEDs, and devices that require fast switching at high voltages or temperatures.
• Industrial Furnaces: SiC serves in refractory linings and as heating elements owing to its thermal durability.

Recent Developments
Research Breakthroughs: Efforts such as at IIT Madras have focused on extracting SiC from simulated lunar soil, indicating potential for advanced space applications.

Physical and Chemical Data (Selected)

Property	Value
Chemical Formula	SiC
Density	3.21 g/cm³
Melting Point	2,730 °C
Solubility	Insoluble in water
Electrical Conductivity	Semiconductor

 
Silicon carbide’s unique features make it central in many emerging technologies and high-performance engineering fields. To highlight the plight of the Katkari Tribe, the Shramjeevi Organisation will hold a two-day protest featuring silent fasts and symbolic lamps, demanding land rights, unpaid wages, and dignity for the marginalised community.

About Katkari Tribe
The Katkari tribe is a Particularly Vulnerable Tribal Group (PVTG) primarily found in the state of Maharashtra and some parts of Gujarat, India. 

Key Information

• Alternate Names: They are also known as "Kathodis," a name derived from their historical occupation of making and bartering katha (catechu), a thickened sap extracted from the wood of the Khair (Acacia catechu) tree.
• Location and Population: The majority of the population (around 235,022 as per the 2011 census data) is concentrated in the Raigad and Thane districts of Maharashtra. A smaller population resides in parts of Gujarat.
• Lifestyle and Occupations: Historically, the Katkari were forest dwellers with a semi-nomadic lifestyle, relying on hunting, fishing, and gathering forest products like firewood and honey. Due to colonial forest laws and modern restrictions, their traditional way of life has been disrupted. Many now work as agricultural or bonded laborers in brick kilns and on plantations, often living in temporary huts made of bamboo and other found materials.
• Culture and Traditions: They have a patriarchal system but tend to live in nuclear rather than joint families. They speak the Katkari language, a dialect of Marathi-Konkani, among themselves, and Marathi with non-tribals. They are notable as one of the few tribal communities in India that traditionally consumed rodents, believing it contributed to their strength and long life.
• Vulnerability: The Katkari face significant challenges including poverty, debt, lack of access to basic facilities (water, housing, healthcare, education), and social exclusion. Their historical listing under the British Raj's Criminal Tribes Act of 1871 also contributed to an enduring stigma. 

Current Status
The Katkari community faces ongoing marginalization and economic insecurity. Government schemes and non-governmental organizations are working to advocate for their rights and improve their socio-economic status through initiatives like the Pradhan Mantri Van Dhan Yojana, which aims to improve tribal income through value addition of forest products. 
 

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