CAUTION FOR ARACHNOPHOBES
Beware, there's a beastie in PrehiScotInktoberfest 11! Well, technically not a spider... Let me explain.
Back at the turn of the 20th Century, while mapping near the wee
village of Rhynie, incredibly rich and detailed fossil remains from the
Devonian period were uncovered: such finds are called Lagerstätte. This
Lagerstätte was called the Rhynie Chert for the village, and it's an extraordinary chunk of rock.
Normally, small animals are rarely fossilised on account of their size:
microscopic fossils even more so. Yet the Rhynie Chert ensconced a
plethora of absolutely tiny creatures, and for decades, was the only
such example of such a find in the world.
So what were these
Well, that wee "spider" resting on a stem is a trigonotarbid
called Palaeocharinus rhyniensis ("ancient Charinus Rhynie dweller"), a beastie unique to Scotland. It was
only 4mm long, but it is very special, for trigonotarbids are among the
earliest known land predators. I use "spider" in inverted commas,
because they are far more primitive arachnids from before the time of
spiders - though arachnophobes might find it a minor distinction!
Palaeocharinus is notable for its eyes: not only those two beady ones in
the middle, but two big lumps beside them with multiple lenses -
theorised to be a link between compound eyes, and the many eyes of later
As a landlubber, Palae-boy can only observe the
shapes beneath the water's surface: furthest left is another Scotland
original, Heterocrania rhyniensis is a euthycarcinoid, a weird arthropod
thingy that's believed to be the ancestor of mandibulates (the group
that includes myriapods like centipedes, crustaceans, and modern
insects); furthest right is Castracollis wilsonae, a particularly
advanced brachiopod, which are almost as common as trilobites in
Scotland; lurking ominously in the background is Lepidocaris rhyniensis,
the most common animal of the Rhynie Chert, which occupies its own
family among the crustaceans.
They may not be as spectacular as
the dinosaurs, but the Rhynie Chert fossils are amazing for the glimpse
they offer into a world 400 million years passed, and if Water Bears
have taught me anything, it's that the microscopic can be just as
remarkable as the macroscopic.
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