Precyclopyge

Precyclopyge binodosa is a Llanvern species of trilobite from the Ordovician. This specimen has been fossilized amongst a fine sequence of thin sedimentary layers most likely deposited on the bottom of a sheltered shallow sea.

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Borthaspis

The Welsh hills are full of sedimental shales that contain Trilobites.  This example is from the Tremadoc near Tremadoc on the Llynn Peninsula.  It shows Borthaspis innotatus, originally an early Illenid trilobite, which was re-assigned to the Asaphida by Sepkoski in 2002.

Phillipsia

This tiny fossil pygidium is just 4mm across.  It is from a specimen of Phillipsia gemmolifera on a small matrix of carboniferous limestione from Derbyshire.  It is an unusual fossilization as many of the derbyshire fossils are pale and the same colour as the matrix.  This rock is full of fossil fragments and crystals.

Rhamphorhynchus

Some pterosaur bones are quite unusual.  This scapulo-coracoid is photographed from both sides.  The glenoid cavity of the shoulder joint can be seen, where the humerus articulates the wing to the body.  Much of the bone is used to anchor the flight muscles and tendons.  This is a resin reproduction 1:1 scale which I made to show the bone structure in full.  It was used to examine the joint articulation and range of movement.

Trinucleus

There are quite a few specimens of Trinucleus fimbriatus in my collections.  Most of them are fragmentary, but this on has preserved the whole carapace in one fossil.  The cephalon is displaced from the pleura, but this is an artifact due to the way the carapace was shed.

Asaphiscus

This small trilobite is a specimen of Asaphiscus wheeleri, from the wheeler shales in Utah, USA.  It is a Cambrian fossil from the St Davids stage.  The margin of the cephalon should be smooth and rounded, but the free cheeks have become partially detached during shedding of the carapace, giving a distorted impression of the cephalon.

Humerus, but unknown!

This small Humerus bone came from the Kem Kem Formation in Morocco.  The ends are missing and the hollow central cavity is suggestive of a bird.  The bone is a little too thick to be Pterosaur material.  With no specific reference material to compare this bone with, it may represent an unknown bird or a small theropod dinosaur.  There are many fossils like this one that end up being labelled “undetermined humerus”.

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