Skip to content Skip to navigation

Article: Isolated graptolites from the Lituigraptus convolutus Biozone (Silurian, Llandovery) of Dalarna, Sweden

Publication: Palaeontology
Volume: 52
Part: 2
Publication Date: March 2009
Page(s): 273 296
Author(s): David K. Loydell and Jörg Maletz
Addition Information

How to Cite

LOYDELL, D. K., MALETZ, J. 2009. Isolated graptolites from the Lituigraptus convolutus Biozone (Silurian, Llandovery) of Dalarna, Sweden. Palaeontology52, 2, 273–296.

Online Version Hosted By

Wiley Online Library
Get Article: Wiley Online Library [Pay-to-View Access] |


Isolated material of 13 graptolite species from the Aeronian (middle Llandovery) Lituigraptus convolutus Biozone is described. A considerable amount of late astogenetic peridermal thickening is revealed in Normalograptus scalaris and Rivagraptus bellulus. As a result, in the former, thecal morphology is modified from climacograptid to pseudoglyptograptid; in both species, the virgella becomes robust. In Metaclimacograptus minimus and Me. sp., it is shown that the dorsal metathecal wall forms the genicular hood, whereas in N. nikolayevi, the infragenicular wall of the succeeding theca forms the distal thecal apertural margin. Pribylograptus argutus exhibits typical pribylograptid thecae along the length of the available rhabdosome fragments. Characters differentiating Campograptus lobiferus from C. harpago include the greater dorso-ventral width and more rapid increase in dorso-ventral width of the former and the greater recurving of distal thecae and presence of thecal spines/processes on all thecae of the latter. Lituigraptus convolutus has rastritiform thecae proximally; thecal apertures throughout the rhabdosome are crescentic and laterally expanded.
PalAss Go! URL: | Twitter: Share on Twitter | Facebook: Share on Facebook | Google+: Share on Google+