Acteocina okeni (Eichwald, 1850)
|
publication ID |
https://doi.org/ 10.26879/936 |
|
persistent identifier |
https://treatment.plazi.org/id/03B287EF-FFF1-3201-DAE6-FBA546CE81DB |
|
treatment provided by |
Felipe |
|
scientific name |
Acteocina okeni (Eichwald, 1850) |
| status |
|
Acteocina okeni (Eichwald, 1850)
Figure 4.2 View FIGURE 4
1850 Bullina okeni Eichwald , p. 146, pl. 11, fig.
17.
1856 Bulla okeni (Eichwald) ; Hörnes, partim, p.
624, pl. 50, fig. 9a-9b.
1935 Bulla okeni (Eichwald) ; Kolesnikov, p. 288-
289, pl. 33, figs. 8-10.
2012 Acteocina okeni (Eichwald) ; O. Anistratenko and V. Anistratenko, p. 123.
Material. 3 specimens from layer 1.
Description. Oval-cylindrical shell with a blunted spire (HS is up to 10 mm; WS is up to 6 mm; WS/ HS is 0.45), consists of 4.5 whorls separated by a horizontal moderately deep suture. Protoconch is heterostrophic. Spire has a wide conical form; before the suture; a well-defined groove is present on the last 1.5-2 whorls. The last whorl is rounded and is about 0.9 of the total shell height. Aperture is slit-shaped, and it widens to the bottom part of the shell and becomes rounded (about 0.8 of the total height of the shell). The aperture outer edge is thin; the inner edge is tightly attached to the shell, forming a well-marked thickening. The shell surface is smooth; growth lines are visible.
Variability. The penultimate whorl is often well-developed due to which the spire has a hemispherical shape with a protoconch protruding from above.
Material. Early and Middle Sarmatian of the Central and Eastern Paratethys (O. Anistratenko and V. Anistratenko, 2012).
| V |
Royal British Columbia Museum - Herbarium |
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.