A dragonfly is a flying insect belonging to the infraorder Anisoptera below the order Odonata. About 3,000 extant species of dragonflies are known. Most are tropical, with fewer species in temperate regions. Loss of wetland habitat threatens dragonfly populations around the world. Adult dragonflies are characterized by a pair of large, multifaceted, compound eyes, two pairs of strong, transparent wings, sometimes with coloured patches, and an elongated body. Many dragonflies have brilliant iridescent or metallic colours produced by structural coloration, making them conspicuous in flight. An adult dragonfly's compound eyes have nearly 24,000 ommatidia each.
Damselflies are flying insects of the suborder Zygoptera in the order Odonata. They are similar to dragonflies but are smaller and have slimmer bodies. Most species fold the wings along the body when at rest, unlike dragonflies which hold the wings flat and away from the body. Damselflies have existed since the Jurassic, and are found on every continent except Antarctica.
The insect family Coenagrionidae is placed in the order Odonata and the suborder Zygoptera. The Zygoptera are the damselflies, which although less known than the dragonflies, are no less common. More than 1,300 species are in this family, making it the largest damselfly family. The family Coenagrionidae has six subfamilies: Agriocnemidinae, Argiinae, Coenagrioninae, Ischnurinae, Leptobasinae, and Pseudagrioninae.
Epiophlebia laidlawi, the Himalayan relict dragonfly, is one of four species of Epiprocta in the family Epiophlebiidae. They have at one time been classified as a suborder Anisozygoptera, considered as intermediate between the dragonflies and the damselflies, partly because the hind wings and fore wings are very similar in size and shape, and partly because the insect at rest holds them back over the body as damselflies do. These attributes now are known to be misleading however; the genus Epiophlebia shares a more recent ancestor with dragonflies and became separated from other Anisoptera in and around the uplifting Himalayas.
Diphlebia is a genus of damselflies in the family Lestoideidae. They are commonly known as rockmasters. These damselflies are very large and thick. The species in this genus are found in Eastern Australia, except for one species that can be found in New Guinea. The males are vividly patterned. They are blue or bluish green and black in colour. Their blue colour also gives them the name azure damselflies. They rest with their wings spread out. Their wings are usually blackish brown or have white markings. These damselflies have several present antenodal crossveins. The two basal crossveins extend across costal and subcostal spaces. The larvae are wide and flat. They have long saccoid gills enabling them to breathe underwater. The inner tooth of their labial palps is elongated. The specific characters of the larvae are mid-ventral, distal width, basal width, and length of median lobe.
The genus Epiophlebia is the sole member of the family Epiophlebiidae, which is itself the sole living representative of the Epiproctan infraorder Epiophlebioptera, and it contains only three species. The first two species were historically placed in their own suborder Anisozygoptera, considered intermediate between dragonflies and damselflies, mainly because the hind wings are very similar in size and shape to the forewings and held back over the body at rest, as in damselflies. It has more recently been recognized that the genus Epiophlebia shares a more recent ancestor with dragonflies, and the group has accordingly been reclassified as an infraorder within the dragonflies. Very recently a third species, Epiophlebia sinensis, has been described from Heilongjiang province in northeast China, bridging Epiophlebia distribution gap between Nepal and Japan. A fourth species has been claimed from larval material from South China, but this is not universally accepted. Epiophlebia species are a freshwater indicator of a river ecosystem health. A study that has been conducted on the head anatomy of Epiophlebia has verified the presence of 41 muscles in the head of the larva. Like in true dragonflies (Anisoptera) the aquatic nymphs breathe through a rectal chamber, but jet propulsion has yet to be documented. Epiophlebia species are a representative of a dragonfly fauna which originated during the Jurassic period on the rising continent of Eurasia.
Austrolestes colensonis, commonly known as the blue damselfly, is a species of damselfly of the family Lestidae. It is endemic to New Zealand and can commonly be found throughout the country, and at any time of the year. It is New Zealand's largest damselfly, and only blue odonate.
Diphlebia coerulescens, known as the sapphire rockmaster, is an Australian species of broad winged damselfly. It is one of a group known as the azure damselflies. It is found in Queensland and north-eastern New South Wales in eastern Australia, where it is found in fast-flowing streams and rivers.
Indolestes tenuissimus is a species of damselfly in the family Lestidae, commonly known as the slender reedling. It is found in north-eastern Australia, New Guinea and on Aru.
Nososticta solitaria is an Australian species of damselfly in the family Platycnemididae, commonly known as the fivespot threadtail. It is found only in north-eastern Australia.
Nososticta coelestina is an Australian species of damselfly in the family Platycnemididae, commonly known as the green-blue threadtail.
Ischnura pruinescens is a damselfly in the family Coenagrionidae, commonly known as the colourful bluetail. The taxon has been assessed for the IUCN Red List as being of least concern and is listed in the Catalogue of Life.
Archibasis mimetes is a species of damselfly in the family Coenagrionidae, commonly known as a blue-banded longtail. It is a medium-sized damselfly; the male is bright blue and black. It has been recorded from New Guinea and northern Australia, where it inhabits streams.
Diphlebia hybridoides is a species of Australian damselfly in the family Lestoideidae, commonly known as a giant rockmaster. It is endemic to north-eastern Queensland, where it inhabits streams in forests.
Diphlebia nymphoides is a species of Australian damselfly in the family Lestoideidae, commonly known as an arrowhead rockmaster. It is endemic to eastern Australia, where it inhabits streams and rivers.
Griseargiolestes eboracus is a species of Australian damselfly in the family Megapodagrionidae, commonly known as a grey-chested flatwing. It is endemic to eastern Australia, where it inhabits bogs.
Griseargiolestes fontanus is a species of Australian damselfly in the family Megapodagrionidae, commonly known as a springs flatwing. It is endemic to south-eastern Queensland and north-eastern New South Wales, where it inhabits streams near their springs.
Episynlestes albicauda is a species of Australian damselfly in the family Synlestidae, commonly known as a southern whitetip. It is endemic to south-eastern Queensland and north-eastern New South Wales, where it inhabits streams and pools in rainforests.
Synlestes tropicus is a species of Australian damselfly in the family Synlestidae, commonly known as a tropical needle. It is endemic to north-eastern Queensland, where it inhabits streams in rainforests.
