A larva ( / ˈ l ɑːr v ə / ; pl. : larvae / ˈ l ɑːr v iː / ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect development such as insects , some arachnids , amphibians , or cnidarians typically have a larval phase of their life cycle .
27-593: Epiophlebia is a genus of damsel-dragonfly native to the Indian subcontinent, East Asia, and Southeast Asia. It is the only living genus of Odonata to neither be a dragonfly nor a damselfly . It is the sole member of the family Epiophlebiidae , which is itself the sole living representative of the infraorder Epiophlebioptera . The bodies of Epiophlebia adults have a distinctive black and yellow striped colouration. Their bodies resemble those of dragonflies, while their wings more closely resemble those of damselflies, with
54-461: A body length of 117 mm (4.6 in) (some sources 125 mm (4.9 in)) and wing span of 160 mm (6.3 in). The longest extant odonate is the Neotropical helicopter damselfly Mecistogaster linearis (Zygoptera: Pseudostigmatidae) with a body length of 135 mm (5.3 in). The smallest living dragonfly is Nannophya pygmaea (Anisoptera: Libellulidae) from east Asia, with
81-633: A body length of 15 mm (0.59 in) and a wing span of 20 mm (0.79 in). The smallest damselflies (and also the smallest odonates) are species of the genus Agriocnemis (Zygoptera: Coenagrionidae) with a wing span of only 17–18 mm (0.67–0.71 in). These insects characteristically have large rounded heads covered mostly by well-developed, compound eyes , which provide good vision, legs that facilitate catching prey (other insects) in flight, two pairs of long, transparent wings that move independently, and elongated abdomens. They have three ocelli and short antennae . The mouthparts are on
108-583: A distinct environment, larvae may be given shelter from predators and reduce competition for resources with the adult population. Animals in the larval stage will consume food to fuel their transition into the adult form. In some organisms like polychaetes and barnacles , adults are immobile but their larvae are mobile, and use their mobile larval form to distribute themselves. These larvae used for dispersal are either planktotrophic (feeding) or lecithotrophic (non-feeding) . Some larvae are dependent on adults to feed them. In many eusocial Hymenoptera species,
135-845: A suborder along with Zygoptera and Anisozygoptera as well-understood and widely preferred terms. Cladogram of Epiprocta after Rehn et al. 2003 : Zygoptera (damselflies) Epiophlebioptera † Isophlebioptera † Heterophlebioptera † Stenophlebioptera † Aeschnidioptera Anisoptera (dragonflies) Cladogram of Odonatoptera including Odonata by Deregnaucourt et al. 2023. † Meganeuridae † Polytaxineuridae † Permaeschnidae † Callimokaltaniidae † Hemizygopteridae † Ditaxineuridae † Iverya † Pirouteliidae † Kargalotypidae † Zygophlebiidae † Moltenophlebiidae † Permophlebiidae † Xamenophlebiidae † Triassologus † Sinotriadophlebiidae † Mitophlebiidae † Paurophlebiidae † Triadophlebiidae † Permagrionidae Larva A larva's appearance
162-467: A wing motion intermediate between those of dragonflies and damselflies. Species of Epiophlebia have a disjunct distribution, occurring in a narrow habitat of cold mountain streams at an altitude of 1,300–3,000 metres (4,300–9,800 ft) with temperatures of around 4–5 °C (39–41 °F) in winter to 16–17 °C (61–63 °F) in summer. The first two species described are Epiophlebia superstes known from Japan and Epiophlebia laidlawi from
189-470: Is a structure on the leading edge near the tip of the wing called the pterostigma . This is a thickened, hemolymph –filled and often colorful area bounded by veins. The functions of the pterostigma are not fully known, but it most probably has an aerodynamic effect and may also have a visual function. More mass at the end of the wing may also reduce the energy needed to move the wings up and down. The right combination of wing stiffness and wing mass could reduce
216-725: Is an order of predatory flying insects that includes the dragonflies and damselflies (as well as the Epiophlebia damsel-dragonflies). The two major groups are distinguished with dragonflies (Anisoptera) usually being bulkier with large compound eyes together and wings spread up or out at rest, while damselflies (suborder Zygoptera ) are usually more slender with eyes placed apart and wings folded together along body at rest. Adult odonates can land and perch, but rarely walk. All odonates have aquatic larvae called naiads or nymphs , and all of them, larvae and adults, are carnivorous and are almost entirely insectivorous , although at
243-487: Is an infraorder) was proposed when it was thought that the "Anisozygoptera" was paraphyletic, composed of mostly extinct offshoots of dragonfly evolution. The four living species placed in that group are (in this treatment) in the infraorder Epiophlebioptera , whereas the fossil taxa that were formerly there are now dispersed about the Odonatoptera (or Odonata sensu lato ). World Odonata List considers Anisoptera as
270-473: Is closely related to mayflies and several extinct orders in a group called the Palaeoptera , but this grouping might be paraphyletic . What they do share with mayflies is the nature of how the wings are articulated and held in rest . Tarsophlebiidae is a prehistoric family of Odonatoptera that can be considered either a basal lineage of Odonata or their immediate sister taxon . The phylogenetic tree of
297-561: Is generally very different from the adult form ( e.g. caterpillars and butterflies ) including different unique structures and organs that do not occur in the adult form. Their diet may also be considerably different. In the case of smaller primitive arachnids, the larval stage differs by having three instead of four pairs of legs. Larvae are frequently adapted to different environments than adults. For example, some larvae such as tadpoles live almost exclusively in aquatic environments, but can live outside water as adult frogs . By living in
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#1732855005521324-505: Is suggested to have split from that of living dragonflies around the end of the Triassic , approximately 205 million years ago. Genetic evidence suggests that the lineage of Epiophlebia arose from the ancient reticulate hybridisation of a lineage related to dragonflies and lineage related to damselflies in propoportions of roughly 67% and 33%, respectively, which may explain why it combines features of both dragonflies and damselflies. The genus
351-471: The Permian of North America, reached wing spans of up to 71 cm (28 in) and a body length of 43 cm (17 in), making it the largest insect of all time. This insect belonged to the order Meganisoptera , the griffinflies, related to odonates but not part of the modern order Odonata in the restricted sense. They have one of the most complete fossil records going back 319 million years. The Odonata
378-503: The Anisoptera. An alternative term warriorfly has been proposed. The largest living odonate is the giant Central American helicopter damselfly Megaloprepus coerulatus (Zygoptera: Pseudostigmatidae) with a wing span of 191 mm (7.5 in). The heaviest living odonates are Tetracanthagyna plagiata (Anisoptera: Aeshnidae) with a wing span of 165 mm (6.5 in), and Petalura ingentissima (Anisoptera: Petaluridae) with
405-558: The abdomen, while dragonfly nymphs respire through an organ in their rectum . Members of the crown group Odonata first appeared during the Late Triassic , though members of their total group , Odonatoptera , first appeared in the Late Carboniferous , making them one of the earliest groups of winged insects. The fossils of odonates and their cousins, including Paleozoic "giant dragonflies" like Meganeuropsis permiana from
432-474: The energy consumption of flying. A pterostigma is also found among other insects, such as bees. The nymphs have stockier, shorter, bodies than the adults. In addition to lacking wings, their eyes are smaller, their antennae longer, and their heads are less mobile than in the adult. Their mouthparts are modified, with the labium being adapted into a unique prehensile organ called a labial mask for grasping prey. Damselfly nymphs breathe through external gills on
459-510: The genus may have been continuous during Pleistocene glacial periods such as the Last Glacial Period , which may explain the genetic similarity of sequenced Epiophlebia species to each other despite the broad geographical range of the genus. Genetic evidence suggests that Epiophlebia is overall more closely related to dragonflies than damselflies, being placed along with dragonflies in the clade Epiprocta . The lineage of Epiophlebia
486-407: The larvae are fed by female workers. In Ropalidia marginata (a paper wasp) the males are also capable of feeding larvae but they are much less efficient, spending more time and getting less food to the larvae. The larvae of some organisms (for example, some newts ) can become pubescent and do not develop further into the adult form. This is a type of neoteny . It is a misunderstanding that
513-520: The larval form always reflects the group's evolutionary history . This could be the case, but often the larval stage has evolved secondarily, as in insects. In these cases , the larval form may differ more than the adult form from the group's common origins. Within Insects , only Endopterygotes show complete metamorphosis, including a distinct larval stage. Several classifications have been suggested by many entomologists , and following classification
540-491: The larval stage they will eat anything that they can overpower, including small fish , tadpoles , and even adult newts . The adults are superb aerial hunters and their legs are specialised for catching prey in flight. Odonata in its narrow sense forms a subgroup of the broader Odonatoptera , which contains other dragonfly-like insects. The scientific study of the Odonata is called odonatology. Johan Christian Fabricius coined
567-437: The northern Indian subcontinent and northern Vietnam. In 2012, a third species, Epiophlebia sinensis , was described from Heilongjiang province in northeast China, bridging Epiophlebia distribution gap between Nepal and Japan. A fourth species, E. diana , has been claimed from larval material from South China, but this is not universally accepted, with some authors considering it a synonym of E. laidlawi. The distribution of
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#1732855005521594-440: The orders and suborders of odonates according to Bybee et al. 2021: Zygoptera (damselflies) [REDACTED] Anisozygoptera [REDACTED] Anisoptera (dragonflies) [REDACTED] In some treatments, the Odonata are understood in an expanded sense, essentially synonymous with the superorder Odonatoptera , but not including the prehistoric Protodonata . In this approach, instead of Odonatoptera,
621-469: The term Odonata in 1793 from the Ancient Greek ὀδών odṓn ( Ionic form of ὀδούς odoús ) "tooth". One hypothesis is that it was because their maxillae are notably toothed. The word dragonfly usually denotes only Anisoptera , but is sometimes used to mean all Odonata. Odonata enthusiasts avoid ambiguity by using the term true dragonfly , or simply anisopteran , when they mean just
648-495: The term Odonatoidea is used. The systematics of the "Palaeoptera" are by no means resolved; what can be said however is that regardless of whether they are called "Odonatoidea" or "Odonatoptera", the Odonata and their extinct relatives do form a clade . The Anisoptera was long treated as a suborder, with a third suborder, the Anisozygoptera (ancient dragonflies). However, the combined suborder Epiprocta (in which Anisoptera
675-484: The underside of the head and include simple chewing mandibles in the adult. Flight in the Odonata is direct , with flight muscles attaching directly to the wings; rather than indirect, with flight muscles attaching to the thorax, as is found in the Neoptera . This allows active control of the amplitude, frequency, angle of attack, camber and twist of each of the four wings entirely independently. In most families, there
702-404: The wings being held over the back when resting like damselflies. Like in true dragonflies (Anisoptera) the aquatic nymphs breathe through a rectal chamber, but jet propulsion (which is found in true dragonflies) has not been observed. Epiophelbia flies relatively clumsily and is less manoverable than dragonflies, preferring to rapidly fly in straight lines in the shade, using a fast wingbeat with
729-610: Was historically placed in the clade "Anisozygoptera" along with a variety of fossil odonatans, primarily from the Jurassic period, but this grouping was later shown to be non- monophyletic , representing a paraphyletic group, with many "anisozygopterans" more closely related to dragonflies than to Epiophlebia . The extinct family Burmaphlebiidae from the mid Cretaceous Burmese amber of Myanmar, dating to around 100 million years ago, may represent true close relatives of Epiophlebia . Odonata For extinct groups, see text Odonata
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