Rhyniognatha

Taxobox
name = "Rhyniognatha"
fossil_range = Fossil range|400Early Devonian


image_width = 250px
image_caption = "Rhyniognatha hirsti"
domain = Eukaryota
regnum = Animalia
phylum = Arthropoda
classis = Insecta
genus = "†Rhyniognatha"
genus_authority = Tillyard, 1928
species = "†R. hirsti"
binomial = "†Rhyniognatha hirsti"
binomial_authority = Tillyard, 1928
synonyms ="Rhyniella praecursor" ("partim")

"Rhyniognatha hirsti" is the world’s oldest known insect. It emerged very early during the Early Devonian Period, around 400 million years ago, when earth’s first terrestrial ecosystems were being formed. While "Rhyniognatha" remains an arthropod of uncertain affinities, several facts are apparent.

Evidence

The head part of a specimen, preserved in a fragment of Rhynie Chert, was collected in 1919 by the Reverend W. Cran, who provided it to S. Hirst, S. Maulik and D.J. Scourfield. Hirst and Maulik published a report in 1926; in it they described "Rhyniella praecursor", which is now known to be a springtail. Several other pieces, including the "Rhyniognatha" head, were also described as "R. praecursor", stating the specimen to be a “supposed larval insect”. The specimen was correctly identified as a different species and renamed "Rhyniognatha hirsti" in 1928 by entomologist Robin J. Tillyard. It was later donated by D.J. Scourfield to the Natural History Museum in London where it is currently displayed on a microscope slide. Scientists have not found much information, but due to the shape of the jaws they think it was probably winged.

Food

Like other insects of its time, "Rhyniognatha" presumably fed on plant sporophylls - which occur at the tips of branches and bear sporangia, the spore-producing organs. The insect’s anatomy might also give clues as to what it ate. The creature had large mandibles which may or may not have been used for hunting.

Wings

Engel & Grimaldi (2004) show that "R. hirsti" was relatively derived within early insects, sharing many characteristics with winged insects. This could mean that "R. hirsti" itself was already winged. [Engel & Grimaldi 2004: Abstract]

Footnotes

References

*cite web |publisher=Natural History Museum |url=http://www.nhm.ac.uk/nature-online/earth/fossils/article-oldest-insect-fossil/the-oldest-fossil-insect-in-the-world.html |title=The oldest fossil insect in the world |author=Andrew Ross
*cite journal |quotes=no |author=Michael S. Engel & David A. Grimaldi |year=2004 |title=New light shed on the oldest insect |journal=Nature |volume=6975 |pages=627–630 |doi=10.1038/nature02291

External links

*cite news |publisher=BBC News |url=http://news.bbc.co.uk/2/hi/science/nature/3478915.stm |title=Oldest insect delights experts |date=2004-02-11 |author=Paul Rincon