Tetragraptidae is an extinct family of
graptolite
Graptolites are a group of colonial animals, members of the subclass Graptolithina within the class Pterobranchia. These filter-feeding organisms are known chiefly from fossils found from the Middle Cambrian ( Miaolingian, Wuliuan) through t ...
s from the
Floian
The Floian is the second stage of the Ordovician Period. It succeeds the Tremadocian with which it forms the Lower Ordovician series. It precedes the Dapingian Stage of the Middle Ordovician. The Floian extended from to million years ago. The ...
to
Darriwilian
The Darriwilian is the upper stage of the Middle Ordovician. It is preceded by the Dapingian and succeeded by the Upper Ordovician Sandbian Stage. The lower boundary of the Darriwilian is defined as the first appearance of the graptolite species ' ...
epochs of the
Ordovician Period
The Ordovician ( ) is a geologic period and system, the second of six periods of the Paleozoic Era, and the second of twelve periods of the Phanerozoic Eon. The Ordovician spans 41.6 million years from the end of the Cambrian Period Ma (mill ...
.
Genera
List of genera from Maletz (2014):
*†''
Corymbograptus''
Obut & Sobolevskaya, 1964
*†''
Paratetragraptus''
Obut, 1957
*†''
Pendeograptus''
Bouček & Přibyl, 1951
*†''
Phyllograptus''
Hall, 1858
*†''
Pseudophyllograptus''
Cooper & Fortey, 1982
*†''
Pseudotrigonograptus''
Mu & Lee, 1958
*†''
Tetragraptus''
Salter, 1863
*†''
Tristichograptus''
Jackson & Bulman, 1970
References
Graptolites
Prehistoric hemichordate families
{{Hemichordate-stub