Taxonomy and Nomenclature
- Kingdom: Animalia
- Phylum: Arthropoda
- Class: Insecta
- Order: Odonata
- Suborder: Anisoptera
- Family: Libellulidae
- Genus: Neurothemis
- Species: Neurothemis fluctuans (Fabricius, 1798)
The species epithet fluctuans is derived from Latin, meaning “fluctuating” or “wavering,” possibly referring to the insect’s erratic flight pattern.
Common Names
- Common gliding skimmer
- Common darner (regional usage)
Morphological Description
Adult Neurothemis fluctuans are medium-sized dragonflies, typically measuring 45–55 mm in total length. Males display bright crimson or reddish‑orange coloration on the abdomen and thorax, with clearer wings that may possess faint amber tinges near the base. Females are generally paler, ranging from yellowish‑brown to olive tones, and may exhibit subtle dark markings on the wings. The wings are broad and clear, lacking prominent venation patterns that differentiate them from closely related species.
Distribution
Neurothemis fluctuans is native to South and Southeast Asia. Documented range includes:
- India (including the Western Ghats and northeastern states)
- Sri Lanka
- Bangladesh
- Myanmar
- Thailand, Laos, Vietnam, Cambodia, and Malaysia
- Southern China (Yunnan and Guangdong provinces)
- Indonesia (Sumatra, Borneo, and Java)
Habitat
The species predominantly inhabits lowland freshwater environments such as:
- Slow‑moving streams and rivers
- Ponds, marshes, and rice paddies
- Swampy forest edges
It prefers open, sunlit areas with abundant emergent vegetation, which serve as perching sites for adults and oviposition substrates for females.
Behavior and Ecology
- Flight: Adults are strong fliers, often observed patrolling territories near water bodies. Their flight is characterized by swift, darting movements interspersed with brief hovering.
- Feeding: Both sexes are aerial predators, capturing a variety of small insects (e.g., mosquitoes, flies, and other dipterans).
- Reproduction: Mating typically occurs on perches near water. Females lay eggs in shallow water or on submerged vegetation; eggs develop into aquatic nymphs (larvae) that undergo multiple instars before emergence.
- Seasonality: In tropical regions, adults may be present year‑round, with population peaks corresponding to the rainy season when freshwater habitats expand.
Conservation Status
The International Union for Conservation of Nature (IUCN) currently lists Neurothemis fluctuans as Least Concern. The species is considered widespread and abundant across its range. However, localized threats such as habitat degradation, water pollution, and conversion of wetlands to agriculture could impact regional populations.
Research and Significance
Neurothemis fluctuans is frequently used in ecological studies as an indicator species for freshwater habitat quality due to its sensitivity to water pollution and habitat disturbance. Its conspicuous coloration and relative abundance make it a suitable subject for citizen‑science monitoring programs involving odonate diversity.
References
- IUCN Red List of Threatened Species. Neurothemis fluctuans entry.
- Yang, C.-M., et al. (2005). “Odonata of the Oriental Region.” Journal of Insect Systematics.
- Needham, J. G., et al. (2000). Dragonflies of the World. Smithsonian Institution Press.
This summary consolidates information from peer‑reviewed taxonomic databases and reputable entomological literature.
