Ice Age Dragon Fly
Why in News?
Odonatologists have reconfirmed the presence of the elusive dragonfly species Crocothemis erythraea in the high-elevation regions of the southern Western Ghats. The species had previously been misidentified or overlooked in this region.
UPSC Relevance
Species and their peculiar behavior is often asked in UPSC Prelims.
PYQ
2022
Which of the following is not a bird?
(a) Golden Mahseer
(b) Indian Nightjar
(c) Spoonbill
(d) White Ibis
2024
Consider the following:
- Carabid beetles
- Centipedes
- Flies
- Termites
- Wasps
Parasitoid species are found in how many of the above kind of organisms?
(a) Only two
(b) Only three
(c) Only four
(d) All five
Key Findings on Crocothemis erythraea in the Western Ghats
- Rediscovery of an Elusive Species: Odonatologists have confirmed the presence of the dragonfly species Crocothemis erythraea in the high-elevation regions of the southern Western Ghats. This rediscovery is significant because the species was previously misidentified or overlooked.
An odonatologist is a person who studies or is an expert in the order of insects known as Odonata. This group includes dragonflies, damselflies, and other related insects. The scientific study itself is called odonatology.
- Confusion with a Similar Species: The species was often mistaken for Crocothemis servilia, a more common and widespread dragonfly found in lowland areas. Both species belong to the same genus, and their close resemblance led to the misidentification.
- Geographic Distribution: Before this study, C. erythraea was known to inhabit high-elevation regions in Europe and Asia, including the Himalayas. In contrast, C. servilia is common in India’s lowland habitats. The new findings confirm that both species coexist in the Western Ghats.
- Historical Context: Researchers suggest that C. erythraea likely colonized southern India during the Pleistocene Ice Age. The cooler climate during this period would have allowed the species, which prefers temperate conditions, to extend its range southward into the Western Ghats.
Features of Dragonfly
- Powerful Predators: Dragonflies are effective carnivores as both adults and in their aquatic larval stage, known as nymphs or naiads. As adults, they are skilled aerial hunters, catching and eating other flying insects like mosquitoes, flies, and gnats. They often achieve a remarkable success rate.
- Expert Fliers: They rank among the fastest and most agile insects in the world. They can fly forward, backward, sideways, and even hover in place. This ability comes from their independent movement of two pairs of wings.
- Exceptional Vision: Their most notable feature is their large, multifaceted compound eyes, which cover much of their head. These eyes provide nearly a 360-degree field of vision and are essential for hunting prey in mid-air.
- Aquatic Larval Stage: Most of a dragonfly’s life is spent as a nymph living underwater in ponds, streams, or rivers. This larval stage can last for months or even years. The nymph is also a fierce predator, equipped with a unique extendable jaw for capturing prey.
- Incomplete Metamorphosis: Dragonflies go through incomplete metamorphosis. Their life cycle has three stages: egg, larva (nymph), and adult, skipping the pupal stage that insects like butterflies undergo.
- Distinctive Appearance: Adult dragonflies are recognized by their long, slender bodies, two pairs of strong, transparent or brightly colored wings, and vibrant, often changing colors.
- Dragonfly rest with their wings held out horizontally, which sets them apart from their close relatives, the damselflies, that hold their wings folded back over their abdomens.