T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network


Bristletails (Order: Archaeognatha)

Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Hexapoda
Class: Insecta
Subclass: Monocondylia
Order: Archaeognatha
Families: Machilidae and Meinertellidae
Common name: Jumping bristletails

Archaeognaths is an order of wingless insects consisting of about 350 known species in two families Machilidae and Meinertellidae. Bristletails are among the most primitive of living insects and have been found in fossils in the mid-Devonian period, which was 419.2 to 358.9 million years ago.
They are small insects and are found throughout the world. They have elongated bodies and their backs that are arched, especially over the thorax. They have three long tail-like structures, of which the lateral two are cerci, while the middle medial filament, which is longest, is an epiproct (a plate above the anus). Their antennae are flexible. They have two large compound eyes which meet at the top of the head, and there are three ocelli (a simple eye). The mouthparts are partly retractable, with simple chewing mandibles and long maxillary palps.
Archaeognaths can spring up to 30 cm into the air, by thrusting their abdominal muscles rapidly and forcefully against the ground, providing them lift-off. Hence the common name ‘Jumping bristletails’.
Their exoskeleton is thin and offers little protection against dehydration so the animals accordingly must remain in moist air, such as in cool, damp situations under stones, in rock crevices, under litter or bark. They feed on algae, lichens, and decaying organic detritus.
Archaeognaths undergo simple metamorphosis progressing from egg to nymph to adult. When moulting they cement themselves to a substrate before moulting. The young take about two years to become sexually mature. 

The males of some species perform courtship rituals. During courtship, the males spin a thread from the abdomen, attach one end to the substrate, and attaches a string packages of sperm (spermatophores) along it. After a series of courtship dances, the female picks up the spermatophores and places them on her ovipositor. She then lays a batch of around 30 eggs in a suitable crevice. The young nymphs go through seven moults till becoming an adult. Unlike most insects, the adults continue to moult after reaching adulthood. Archaeognaths can live up to four years and grow up to about 15 mm. long.

The next two photos are of a jumping bristletail on found on Kapiti Island.
  



A lateral aspect photo of an Archaeognathid, showing arched profile and abdominal styli


The head of an Archaeognathid, showing the compound eyes, prominent maxillary palps, and detachable scales.


Thanks to Wikipedia for text and information: https://creativecommons.org/licenses/by-sa/3.0/