Name:
Idmonarachne
(Idmon arachne).
Phonetic: Id-mon-ah-rak-nee.
Named By: R. J. Garwood, J. A. Dunlop,
P. A. Selden, A. R. T. Spencer, R. C. Atwood, N.
T. Vo & M. Drakopoulos - 2016.
Classification: Arthopoda, Chelicerata,
Arachnida, Tetrapulmonata.
Species: I. brasieri (type).
Diet: Insectivore.
Size: Total body length about 11 millimetres
long. Pedipalps 4 mm long. Shortest legs 6.5 mm, longest
leg 8.5 mm.
Known locations: France.
Time period: Stephanian (Gzhelian) of the
Carboniferous.
Fossil representation: Almost complete individual.
Idmonarachne
is one of the oldest ‘spiders’ that we know about, living on our
planet some three hundred million years ago. Idmonarachne
is not
technically a true spider, hence the genus is not currently included
with the Araneae order of arachnids. Idmonarachne
however comes very
close to being called a true spider.
The
holotype specimen of Idmonarachne is tiny, if it
sat on your finger
nail, the body would not extend past the tip of your finger. The
type specimen was found preserved in sedimentary rock, so
computerized tomography was used to reconstruct this ‘spider’,
allowing for perfect reconstruction without risking damaging it by
trying to dig it out of the stone.
The
name Idmonarachne come from the ancient Greek myth
of Arachne, a
woman who challenged the Goddess Minerva to a weaving contest. When
Minerva found that Arachne’s weaving, that of a mortal was as good as
her own, a goddess could do, she flew into a great rage and began
to beat Arachne. Later after Arachne’s death, the gods turned her
into a spider so that Arachne could keep on weaving. Arachne’s father
was called Idmon, and in reference to the genus name the idea is
Idmonarachne is father to the true spiders. This
is not to say the
genus is specifically ‘the’ ancestor, but it represents well the
group that may have spawned the true spiders of the Araneae order.
Further reading
- Almost a spider: a 305-million-year-old fossil arachnid and
spider origins. - Proceedings of the Royal Society B
283:2016125. - R. J. Garwood, J. A. Dunlop, P. A.
Selden, A. R. T. Spencer, R. C. Atwood, N. T. Vo
& M. Drakopoulos - 2016.
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