| 词条 | Clonograptus |
| 释义 |
| image = DiplograptusCaneySprings.jpg | image_caption = Graptolites, like this Amplexograptus from the Ordovician near Caney Springs, Tennessee are good zone fossils. A zone fossil must have a short time span but a common animal of the time. Graptolites became extinct at the end of the Devonian. | regnum = Animalia | phylum = Hemichordata | classis = Graptolithina | ordo = | familia = | genus = Clonograptus | genus_authority = | subdivision_ranks = Species | subdivision = }}Clonograptus is a genus of graptolites. Groups of these animals were connected by stalklike structures to a central region. Species of Clonograptus are zone fossils, that help us estimate a precise age of Ordovician rocks.[1] References1. ^http://www.britannica.com/EBchecked/topic/122072/Clonograptus {{Hemichordate-stub}} 4 : Graptolite genera|Paleozoic life of New Brunswick|Paleozoic life of Newfoundland and Labrador|Paleozoic life of the Northwest Territories |
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