Flowerites sobolewi Dzik, 1984 from the Platyclymenia Zone, Famennian, Łagów-Dule, Poland. 1. Medial section through an adult specimen. 2. Another adult specimen  in dorsal (a) and lateral (b ) views.

Flowerites sobolewi Dzik, 1984; Platyclymenia Zone, Famennian, Łagów-Dule, Holy Cross Mts, Poland; reconstruction of the adult shell (a) and 

longitudinal section through the siphuncle (b).

Diagnoza

Horn-like curved shell elliptic in cross section, with the long axis running dorso-ventrally; surface smooth with indistinct transverse striation; longitudinal
ribs discernible on moulds; gas chambers low; Siphuncle at the inner (concave) side.

Porównanie

Sobolew (1912) figured one relatively large but incomplete specimen. Some additional specimens confirm the correctness of his diagnosis. The "longitudinal ribs discernible in moulds" of Sobolew are the attachment scars of retractor muscles. The dorsal (convex) side of the shell is a little flattened, whereas the ventral side is parabolic in outline. The body chamber is cylindrical without any significant terminal modifications, with a ventral rudimentary funnel sinus. The connecting rings are recrystallized. There are no deposits. The intrapopulation variability consists in shell size and coiling.

The phylogenetic relations of this species are unclear. It may be a descendant of Protophragmoceras (Silurian; Discosorida) or Devonocheilus (Late Devonian; Oncoceratida).

Autekologia

Występowanie geograficzne

Zasięg czasowy

Materiały muzealne

ZPAL N/103 and N/102

Literatura

Dzik, J. 1984. Phylogeny of the Nautiloidea. Palaeontologia Polonica 45, 1-255