Graptolithina
Classification
Phylum: Hemichordata
Class: Graptolithina (Bronn, 1846)
Cincinnatian Orders: Graptoloidea, Mastigograptida
Geologic Range
Middle Cambrian – Carboniferous
Common Paleoecology
Graptolithina is an extinct class of passively mobile planktonic suspension feeders
Characteristics of the Class
- Chitinous exoskeleton with characteristic growth bands and growth lines in periderm
- Thecae arranged in single or double row along stipes
- Rhabdosomes originating in a conical sicula
- Sessile or epiplanktonic
- Attached by nema (or virgula) from apex of sicula
Published Descriptions
Treatise on Invertebrate Paleontology, Part V (1955):
- Colonial marine organisms that secrete a chitinous exoskeleton with characteristic growth bands and growth lines in periderm; thecae arranged in single or double row along stipes, or rarely in less regular aggregates, in some orders polymorphic and related to a chitinized stolon system; rhabdosomes originating in a conical sicula, sessile or epiplanktonic, attached by nema (or virgula) from apex of sicula; stipes free or rarely encrusting.
Graptoloidea
Mastigograptida
