|Portal of graptolites and pterobranchs sponsored by Artistic Embroidery M.M. plus M.
Diagnosis by O.M.B. Bulman (1938):
GRAPTOLOIDEA Lapworth, 1875 emend. auctt.
(inl. Retioloidea and Corynoidea; Rhabdophora
Probably planktonic or pseudoplanktonic, sicula
pendent from nema (or virgula); stipes pendent to
scandent in relation to this, uniserial, biserial or
rarely quadriserial; rhabdosome generally of few
stipes, which are almost invariably composed of
Tremadocian to Upper Silurian (? Devonian).
- - -
Diagnosis by O.M.B. Bulman (1955):
GRAPTOLOIDEA Lapworth, 1875
Planktonic or epiplanktonic Graptolithina, sicula
pendent to scandent in relation to this, uniserial or
biserial); rhabdosome generally of few stipes,
comprising only one type of theca (autotheca). L.
Ord. - U. Sil.
- - -
Diagnosis by O.M.B. Bulman (1970):
GRAPTOLOIDEA Lapworth, 1875 [nom. transl.
Ruedemann, 1904, p. 573 (ex section Graptoloidea
Lapworth, in Hopkinson & Lapworth, 1875, p.633)]
[=suborder Rhabdophora Allman 1872, p.380].
L. Ord. - U. Sil.
|Reconstruction of Loganograptus kjerulfi Herrmann
from the Lower Ordovician.
From Obut (1964)
The Graptoloidea are planktonic or epiplanktonic
graptolites. They have been reported from the
Lower Ordovician to the Middle Devonian. Before
becoming extinct, they exhibit three evolutionary
The Graptoloidea are useful in stratigraphy.
Many forms have an almost world-wide distribution.
Some genera (eg., Diplograptus, Didymograptus
and Monograptus) have been recorded from all six