Tuesday, 14 November 2017
PrehiScotInktoberfest Day 14: Silvanerpeton miripedes & Pulmonoscorpius kirktonensis
PrehiScotInktoberfest 14 returns to the undergrowth, but this time back to the primeval Devonian, and the beasties are quite a bit nastier than the furry critters of the Jurassic!
So, it's established that if you're going to talk about ancient tetrapods, Scotland is where you go. Today's tetrapod, seen scurrying in the foreground of what is now East Kirkton Quarry, is Silvanerpeton miripedes ("Woodland crawler with wonderful feet"), only about 30cm long - the length of a ruler. Silva is particularly important in the fossil record, as it lived right in a period known as Romer's Gap - a period of some 25 million years where fossil tetrapods are poorly known. Since tetrapods were the ancestors of reptiles, birds, and mammals, it's a pretty crucial period to be lost to science. We know plenty about the four-legged beasties before 360 MYA & after 345 MYA, but Romer's Gap eluded scientists for years.
You may have noticed Silvanerpeton isn't alone in this image. Crashing through the ferns is the monstrous Pulmonoscorpius kirktonensis ("Lung scorpion of Kirkton"), who might be one of the reasons tetrapods are so rare in Romer's Gap! Pulmo here is one of the largest land-dwelling scorpions yet discovered, a colossal 70cm/28 inches, with claws like kitchen scissors and a stinger the size of a hen's egg. You know the rule of thumb with scorpions, where thin tails & big claws = less venomous, & thick tails & thin claws = more venomous? Pulmo had a very thick tail - which sounds like bad news for tetrapods like Silva.
"'Mon wee Silva! Gies a hug!"
"Wi thay claws? Nae chance!"
"Ach go oan!"
"HALP! HALP! TETRAPOD OPPRESSION!"