''Petalura hesperia'', more commonly known as the western petaltail or giant western dragonfly, is a species of

dragonfly A dragonfly is a flying insect belonging to the infraorder Anisoptera below the order Odonata. About 3,000 extant species of true dragonfly are known. Most are tropical, with fewer species in temperate regions. Loss of wetland habitat threate ...

in the family

Petaluridae The petaltails of the family Petaluridae are apparently the most ancient of the extant true dragonflies (infraorder Anisoptera), having fossil members from as early as the Jurassic (over 150 million years ago). Modern petalurids include only 11 ...

, originating from

Western Australia Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...

. It resides near the south-western coast of Australia, often observed near drainage basins. ''Petalura hesperia'' lives along streams and rivers where it lays its

larvae A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. The ...

Larvae

''Petalura hesperia'' lay their larvae along stream margins because '' Petalura'' larvae are semiaquatic, and the larvae create a burrow in the mud along the sides of rivers or streams to serve as protection. They can burrow deeper into mud during dry summers to keep their skin moist. Even as larvae this species is a

nocturnal Nocturnality is an animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnal meaning the opposite. Nocturnal creatures generally have highly developed sens ...

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

, feeding off of other species larvae and small insects such as cockroaches and spiders residing near their burrows along

lotic River ecosystems are flowing waters that drain the landscape, and include the Biotic component, biotic (living) interactions amongst plants, animals and micro-organisms, as well as abiotic (nonliving) physical and chemical interactions of its man ...

fresh water Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. Although the term specifically excludes seawater and brackish water, it does include ...

on lowland, or sometimes in rainforests located on upland.

Adults

Adult dragonflies from the genus ''Petalura'' are commonly known as 'petaltails' because of the male's anal appendages, which can vary in color. Adults of this species live near streams and rivers, and are semiaquatic, living quite like their larvae. They are also nocturnal predators, although they tend to feed off of larger larvae, ones with extended

phase Phase or phases may refer to: Science *State of matter, or phase, one of the distinct forms in which matter can exist *Phase (matter), a region of space throughout which all physical properties are essentially uniform * Phase space, a mathematic ...

s, and larger sized bugs than that of what their larvae eat. Adults mate on

vegetation Vegetation is an assemblage of plant species and the ground cover they provide. It is a general term, without specific reference to particular taxa, life forms, structure, spatial extent, or any other specific botanical or geographic character ...

, then the females lay their egg larvae in old plant matter. Adults live for 4–6 months. Species of the genus ''Petalura'' tend to be univoltine while many other species may take a few years to complete their life cycles.

Gallery

Petalura hesperia female wings (34921038441).jpg, Female wings Petalura hesperia male wings (34665002010).jpg, Male wings

References

{{Taxonbar, from=Q3062712 Petaluridae Odonata of Australia Insects of Australia Endemic fauna of Australia Taxa named by J.A.L. (Tony) Watson Insects described in 1958