Hemichordate: Difference between revisions
Content deleted Content added
mNo edit summary |
No caps on chordates; surving -> surviving |
||
Line 1: | Line 1: | ||
[[de:Kiemenlochtiere]] |
[[de:Kiemenlochtiere]] |
||
'''Hemichordata''' is a [[Phylum (biology)|phylum]] of [[deuterostome]] [[animal]]s, generally considered the sister group of our own, the [[ |
'''Hemichordata''' is a [[Phylum (biology)|phylum]] of [[deuterostome]] [[animal]]s, generally considered the sister group of our own, the [[chordate]]s. They date back to the Lower or Middle [[Cambrian]] and include an important class of [[Fossil|fossils]] called [[graptolite]]s, most of which became extinct in the [[Carboniferous]]. One surviving species is known, ''[[Cephalodiscus graptolitoides]]''. |
||
All other modern forms are marine worms, commonly called [[acorn worm]]s. |
All other modern forms are marine worms, commonly called [[acorn worm]]s. |
||
They are divided into two classes: the [[Enteropneusta]] and the [[Pterobranchia]]. |
They are divided into two classes: the [[Enteropneusta]] and the [[Pterobranchia]]. |
Revision as of 16:47, 12 April 2004
Hemichordata is a phylum of deuterostome animals, generally considered the sister group of our own, the chordates. They date back to the Lower or Middle Cambrian and include an important class of fossils called graptolites, most of which became extinct in the Carboniferous. One surviving species is known, Cephalodiscus graptolitoides.
All other modern forms are marine worms, commonly called acorn worms. They are divided into two classes: the Enteropneusta and the Pterobranchia.