Rhyniella praecursor
Encyclopedia
Rhyniella praecursor is a fossil
springtail
from the Rhynie chert
formed during the Pragian stage of the Early Devonian; for some time it was believed to be the only hexapod
from the Early Devonian . It is a very primitive member of the Collembola, far too basal to be classified in any of the living order
s of springtails.
Its remains were discovered in 1919. Reconstructed from the scattered bits and pieces of its exoskeleton, R. praecursor was described in 1926, and at first believed to be a larva
l insect
.
Mouthparts
initially assigned to R. praecursor were redescribed as Rhyniognatha hirsti in 1928. In 2004, Rhyniognatha hirsti was found to be an insect, the oldest known to date. The debate and uncertainties that for long surrounded these primitive hexapods shows that by 400 million years ago, springtail and insect ancestors were still so much alike to be easily confused.
Rhyniella grew to a length of about 0.5 inches (1.3 cm) and would have been a scavenger, feeding on rotting matter.
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
springtail
Springtail
Springtails form the largest of the three lineages of modern hexapods that are no longer considered insects...
from the Rhynie chert
Rhynie chert
The Rhynie chert is an Early Devonian sedimentary deposit exhibiting extraordinary fossil detail or completeness . It is exposed near the village of Rhynie, Aberdeenshire, Scotland; a second unit, the Windyfield chert, is located some 700 m away...
formed during the Pragian stage of the Early Devonian; for some time it was believed to be the only hexapod
Hexapoda
The subphylum Hexapoda constitutes the largest grouping of arthropods and includes the insects as well as three much smaller groups of wingless arthropods: Collembola, Protura, and Diplura . The Collembola are very abundant in terrestrial environments...
from the Early Devonian . It is a very primitive member of the Collembola, far too basal to be classified in any of the living order
Order (biology)
In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...
s of springtails.
Its remains were discovered in 1919. Reconstructed from the scattered bits and pieces of its exoskeleton, R. praecursor was described in 1926, and at first believed to be a larva
Larva
A larva 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...
l insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
.
Mouthparts
Insect mouthparts
Insects exhibit a range of mouthparts, adapted to particular modes of feeding. The earliest insects had chewing mouthparts...
initially assigned to R. praecursor were redescribed as Rhyniognatha hirsti in 1928. In 2004, Rhyniognatha hirsti was found to be an insect, the oldest known to date. The debate and uncertainties that for long surrounded these primitive hexapods shows that by 400 million years ago, springtail and insect ancestors were still so much alike to be easily confused.
Rhyniella grew to a length of about 0.5 inches (1.3 cm) and would have been a scavenger, feeding on rotting matter.