Flowerites sobolewi Dzik, 1984 from the Platyclymenia Zone, Famennian in Łagów-Dule, Poland. 1. Medial section through and adult specimen ZPAL N/103. 2. Adult specimen ZPAL N/I02 in dorsal (a) and lateral (b ) views.
Horn-like curved shell elliptic in cross section, with the long axis running dorso-ventrally. Shell smooth, with indistinct transverse striation. Longitudinal ribs discernible in moulds. Air 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 this 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
Literatura
Dzik, J. 1984. Phylogeny of the Nautiloidea. Palaeontologia Polonica 45, 1-255
Specyfikacja
Królestwo ANIMALIA
Typ MOLLUSCA
Podtyp CONCHIFERA
Gromada CEPHALOPODA
Podgromada NAUTILOIDEA
Rząd Discosorida
Rodzaj Flowerites
Gatunek Flowerites sobolewi
Synonimy Cyrtoceras ellipticum n. sp.; SOBOLEW 1912, non Cyrtoceras ellipticum LOSSEN, 1860,
Populacja typowa gatunku
Holotyp
Sobolew 1912,(probably stored at the Charkov University).