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).
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.
is one of the oldest ‘spiders’ that we know about, living on our
planet some three hundred million years ago. Idmonarachne
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.
- 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.