Fig. 3 in Phyletic evolution and iterative speciation in the persistent Pristiograptus dubius lineage

Fig. 3. Morphology of graptolite Pristiograptus rhabdosomes. A. Drawing of rhabdosome showing its characters (modified from Radzevičius 2003). B–E. Morphological features on flattened specimens. B. Pristiograptus lodenicensis Přibyl, 1948; VU−813, Likënai−396 borehole, Lithuania, depth 589.5 m; Cyrtograptus lundgreni Biozone, Riga Formation. C. Pristiograptus dubius magnus subsp. nov., VU−835, Parovėja−9 borehole, Lithuania, depth 599.8 m; Cyrtograptus perneri Biozone, whole specimen (C1), enlargement showing thecal apertural lip (C2). D. Pristiograptus dubius pseudodubius (Bouček, 1932), fragment of rhabdosome, VU−A3−0047a; C. lundgreni Biozone, Żdanów outcrop, Sudetes, Poland. E. Pristiograptus jaegeri Holland, Rickards, and Warren, 1969; Vilkaviškis−131 borehole, depth 1073.2 m, VU−8004, Colonograptus deubeli Biozone. Abbreviations: ss, angle between thecal lip and wall of succeeding theca; λ, angle between interthecal septum (thecal axis) and virgule; r, sicula ring; th1, first theca; tal, thecal apertural lip.