A fossil marine invertebrate animal of the Palaeozoic era, forming mainly planktonic colonies and believed to be related to the pterobranchs.
- Class Graptolithina, phylum Hemichordata
More example sentences
- The Ordovician is best known for the presence of its diverse marine invertebrates, including graptolites, trilobites, brachiopods, and the conodonts (early vertebrates).
- Other marine fossils commonly found throughout the Silurian record include trilobites, graptolites, conodonts, corals, stromatoporoids, and mollusks.
- To return to our example, the usual biostratigraphic markers in Middle Paleozoic stratigraphy are graptolites, conodont ‘jaw’ parts, and thelodont scales.
Definition of graptolite in:
- The US English dictionary