genus D dorsoplicatum ( Abich, 1878 )

Korn, Dieter & Ghaderi, Abbas, 2025, Late Permian nautiloids from Julfa (NW Iran), European Journal of Taxonomy 1018, pp. 1-113 : 73

New genus D dorsoplicatum ( Abich, 1878)

Fig. 3A–B

Nautilus dorso plicatus Abich, 1878: 23 , pl. 2 fig. 6, pl. 3 fig. 1, pl. 4 fig. 8.

Coelonautilus dorsoplicatus – von Arthaber 1900: 217.

Tainoceras dorsoplicatum – Shimansky 1965a: 41, pl. 14, fig. 1.

Remarks

Abich (1878) illustrated two fragments as “ Nautilus dorso plicatus , nov. form.”. The first of these ( Abich 1878: pl. 4 fig. 8) has a whorl height of about 27 mm. It shows rounded, strongly convergent flanks and a venter with a longitudinal midventral groove about 15 mm wide ( Fig. 3B ). This groove is bordered on both sides by a slightly raised margin that is decorated with large, blunt nodes. Ventrolateral nodes are obviously lacking. The suture line has a fairly narrow, rounded lobe on the venter and a broad, rounded lobe on the flank.

The second specimen ( Abich 1878: pl. 2 fig. 3, pl. 3 fig. 1) has a whorl width of about 35 mm ( Fig. 3A ) and corresponds to the larger one in conch shape and sculpture. The specimen has a broadly rounded umbilical margin. It shows that there are neither ventrolateral nor umbilical nodes; the flank appears to be smooth.

New genus D dorsoplicatum occupies a morphologically isolated position in the family Tainoceratidae due to the presence of only a single row of ventral nodes. The species is probably not represented in the new collections from NW Iran.

Figures

Fig. 3. Reproductions of nautiloid figures of Abich (1878). A. “Nautilus dorso plicatus” Abich, 1878. B. “Nautilus dorso plicatus”. C. “Nautilus dorso armatus” Abich, 1878. D. “Nautilus incertus” von Arthaber, 1900. E. “Nautilus Pichleri” von Arthaber, 1900. F. “Nautilus tubercularis” Abich, 1878. Scale bar units =1 mm.