Life Through Geologic Time

I'm just a Paleobiology major trying to share the beauty of the past, praise silt, and all of its wonders yet to be uncovered.

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Catching Elephant is a theme by Andy Taylor

 

Living Fossils - Liphistiidae

Liphistiidae is a family of spiders that contains 5 genera and 85 species, now you might be thinking that that isn’t very meaningful taxonomically, but this family of spiders is extremely basal, which if you’ll remember, is the main factor which classifies an organism as a living fossil.

These spiders are non-venomous and live in tubes, and should not be confused with Trapdoor spiders, or other spider families that also live in burrows, tubes, or crevices. These spiders are characterized by their downward pointed chelicerae (mouth parts,) and segmented series of plates on their abdomens. They are nocturnal, and the males wander searching for females, who generally stay in their burrows, waiting for prey. They have low activity, which may be because they have book lungs. They may also be found in caves where they live in natural retreats, which are still sealed off with a rudimentary silken door. Pictured above is the well known Kimura-gumo (Heptathela kimurai,) of Japan, and I believe both are female.

In burrow:

By Akio Tanikawa (http://spider.fun.cx/okinawa/yanbarukimuragumo.htm) [CC-BY-SA-2.5 (www.creativecommons.org/licenses/by-sa/2.5)], via Wikimedia Commons

Spider:

By Akio Tanikawa (http://spider.fun.cx/okinawa/yanbarukimuragumo.htm) [CC-BY-SA-2.5 (www.creativecommons.org/licenses/by-sa/2.5)], via Wikimedia Commons

Scutosaurus (Shield Reptile), not to be confused with Sauropelta was a large, armoured, herbivorous pareiasaur, which is a synapsid that lived in the Permian with stocky bodies, short tails, and highly sculpted and adorned skulls. That’s right, synapsid, not dinosaur. Learn more about synapsids with my here. Scutosaurus is found in the Russian Permian beds, with some found standing, suggesting that they got stuck in mud or swamps while feeding. It was likely aquatic, but being that many fossils have been found mired in mud, it may be unlikely. Unlike most reptiles, Scutosaurus held its legs beneath it to support its great weight, rather than side sprawling, only endothermic vertebrates are known to do this today. It likely had well developed hearing due to a slender bone found in its ear.

Scutosaurus (Shield Reptile), not to be confused with Sauropelta was a large, armoured, herbivorous pareiasaur, which is a synapsid that lived in the Permian with stocky bodies, short tails, and highly sculpted and adorned skulls. That’s right, synapsid, not dinosaur. Learn more about synapsids with my here. Scutosaurus is found in the Russian Permian beds, with some found standing, suggesting that they got stuck in mud or swamps while feeding. It was likely aquatic, but being that many fossils have been found mired in mud, it may be unlikely. Unlike most reptiles, Scutosaurus held its legs beneath it to support its great weight, rather than side sprawling, only endothermic vertebrates are known to do this today. It likely had well developed hearing due to a slender bone found in its ear.