Trilobite Anatomy

In trilobites the pygidium can range from extremely small much smaller than the head or cephalon to larger than the cephalon. The trilobite in the same picture is calymene blumenbachii.

What Were Trilobites Oxford University Museum Of Natural

Cyclopyge early to late ordovician.

Trilobite anatomy. Both lived in silurian great britain. Trilobites occupied different levels of the food web including predator scavenger and prey. Similarly our knowledge of the internal anatomy of trilobites is very poorly understood.

In insects head is a preferred term. Selenopeltis early to late ordovician. Sometimes the gut or its contents are also preserved as an axial structure.

Trilobites evolved profound adaptations that place them among the most successful of all early animals. Trilobite means three lobes this refers to their body plan. This category contains anatomical features of trilobites.

Only about twenty different species of trilobites have been found with preservation of antennae and limbs. They can be smooth as in order asaphida or spiny as in order lichida. Once soft part anatomy had been recovered the trilobites were originally allied to the crustacea.

X ray images of some trilobite specimens indicate a long central axial structure typically considered an alimentary canal intestines or gut. A relationship with the chelicerata in a clade termed arachnomorpha arachnata was in vogue for some time58 but a more recent analysis of panarthropoda suggests the trilobites are one of two major branches of artiopoda30. They patrolled hunted and scoured the oceans for over 270 million years.

Both lived in silurian great britain. Some of the genera of trilobites appearing in the ordovician include. Such characteristics as occipital lobes anterior margins and facial sutures which allowed early trilobites to shed their molting shell were shared by the majority of trilobite species as were such exotic sounding features as axial rings articulating facets and pleural spines.

To the right is an example of the olenid trilobite triarthrus eatoni showing preserved antennae legs and gill filaments. Taken together a listing of such morphological features provides nothing less than a plethora of tongue twisting trilo terms.

Trilobite Anatomy Study By Rustedbones On Deviantart