Sigmagraptidae | |
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Scientific classification | |
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Family: | Sigmagraptidae Cooper & Fortey, 1982 |
Sigmagraptidae is an extinct family of graptolites. [1]
List of genera from Maletz (2014): [2]
Graptolithina is a subclass of the class Pterobranchia, the members of which are known as graptolites. These organisms are colonial animals known chiefly as fossils from the Middle Cambrian through the Lower Carboniferous (Mississippian). A possible early graptolite, Chaunograptus, is known from the Middle Cambrian. One analysis suggests that the pterobranch Rhabdopleura represents extant graptolites. Studies on the tubarium of fossil and living graptolites showed similarities in the basic fusellar construction and it is considered that the group most probably evolved from a Rhabdopleura-like ancestor.
Monograptidae is an extinct family of graptolites of the Order Graptoloidea. Monograptids have only one row of thecae per stipe, unlike the biserial graptolites which have two opposing rows of thecae per stipe.
Anisograptidae is an extinct family of graptolites. As the first planktic graptolites, they play a crucial role for understanding the transition of graptolites from ocean floor suspension feeders to ocean surface plankton during the early Ordovician.
Dichograptidae is an extinct family of graptolites. Fossils are found mostly from the Late Ordovician to the Early Devonian.
Didymograptidae is an extinct family of graptolites.
Tetragraptidae is an extinct family of graptolites from the Floian to Darriwilian epochs of the Ordovician Period.
Glossograptidae is an extinct family of graptolites.
Diplograptidae is an extinct family of graptolites.
Lasiograptidae is an extinct family of graptolites.
Climacograptidae is an extinct family of graptolites.
Dicranograptidae is an extinct family of graptolites.
Normalograptidae is an extinct family of graptolites.
Neodiplograptidae is an extinct family of graptolites.
Retiolitidae is an extinct family of graptolites characterized by meshwork-like tubaria.
Dimorphograptidae is an extinct family of graptolites.
Dendrograptidae is an extinct family of graptolites.
Acanthograptidae is an extinct family of graptolites.
Cysticamaridae is an extinct family of graptolites.
Dithecodendridae is an extinct family of graptolites.
Cyclograptidae is an extinct family of graptolites.
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