Trilobites are an extinct example of, for 10 points, what exoskeleton-possessing animals, such as crustaceans and insects?
In a paper subtitled "The Endless Dispute," Jacob Rempel summarized the difficulty of determining the evolutionary origin of the head of animals in this phylum due to the nebulous nature of the pre-oral region and the labrum. Several thin R cells form a transparent structure called a rhabdom in members of this phylum. Rift Valley fever and West Nile are caused by arboviruses, meaning that they are transmitted by members of this phylum. Animals in this phylum absorb wastes from their hemolymph through a system of Malpighian tubules. Until recently, the start of the Cambrian Period was dated to the appearance of a three-lobed animal in this phylum. Trilobites are an extinct example of, for 10 points, what exoskeleton-possessing animals, such as crustaceans and insects?
In a paper subtitled "The Endless Dispute," Jacob Rempel summarized the difficulty of determining the evolutionary origin of the head of animals in this phylum due to the nebulous nature of the pre-oral region and the labrum.
Euarthropoda [or arthropods; accept insects until “this phylum” is read] &lt;Biology&gt;