Diplograptidae

Classification
Phylum: Hemichordata
Class: Graptolithina
Order: Graptoloidea
Family: Diplograptidae (Lapworth, 1873)
Cincinnatian Genera: Arnheimograptus, Geniculograptus

Geologic Range
Late Ordovician – Late Silurian

Common Paleoecology
Diplograptidae is an extinct family of passively mobile planktonic suspension feeders

Description of the Family

  • Scandent biserial, with straight stripes
  • Median septum may be present or absent, or partially present
  • Thecae straight or with carrying degrees of sigmoidal curvature
  • Unspined or with apertural or mesial spines restricted to base of rhabdosome
  • Rhabdosome oval, circular or rectangular in cross section

Published Descriptions

Treatise on Invertebrate Paleontology, Part V (1955):

  • Scandent biserial, with straight stripes, adnate dorsally, with or without median septum or with incomplete or partial septum; thecae straight or with carrying degrees of sigmoidal curvature; usually unspined or with apertural or mesial spines restricted to base of rhabdosome, which is oval, circular or rectangular in cross section; periderm continuous, rarely attenuated or supported by lists; development of diplograptid type.

Arnheimograptus


Geniculograptus