An overlooked diversity-the Costellariidae (Gastropoda: Neogastropoda) of the Miocene Paratethys Sea
Author
Harzhauser, Mathias
0000-0002-4471-6655
mathias.harzhauser@nhm-wien.ac.at
Author
Landau, Bernard
0000-0002-4471-6655
mathias.harzhauser@nhm-wien.ac.at
text
Zootaxa
2021
2021-06-09
4982
1
1
70
journal article
https://doi.org/10.11646/zootaxa.4982.1.1
f68b381d-d0dd-44e2-b9fe-6cf3c1aab1fa
1175-5326
4921842
58388FB8-128A-4381-83D1-3C508D0D3873
Bellardithala
sp.
Figs 8G
Vexillum
(
Uromitra
)
sp.—
Tomašových 1998: 378
, pl. 10, figs 3–4.
Material.
Inv.
Z23408
-P2003/27,
Natural History Museum in
Bratislava
, SL:
9.4 mm
, MD:
3.3 mm
.
Description.
Shell medium-sized, moderately slender with slightly gradate spire. Protoconch and first teleoconch whorls unknown. Early teleoconch whorls with broad, strongly opisthocline axial ribs, with interspaces of similar width. Axial ribs becoming sigmoidal and densely beaded on later whorls, with two more spiral rows of slightly more prominent beads along adapical suture. About eight spiral rows of beads on penultimate whorl. Beads replaced by prominent, convex spiral cords on strongly constricted base. Aperture is largely destroyed with three prominent columellar folds and much weaker abapical fourth fold. Siphonal canal long.
Discussion.
Tomašových (1998)
described a single fragmentary specimen of a
Bellardithala
from basinal clays at Devínska Nová Ves. Due to its peculiar sculpture of strongly opisthocline to sigmoidal, beaded axial ribs, this specimen differs from all other Paratethyan
Bellardithala
species
and might represent a yet undescribed species. Due to its fragmentary preservation, we refrain from naming it formally.
Palaeoenvironment.
The mollusc assemblage of Devínska Nová Ves indicates deeper neritic environments (
Tomašových 1998
).
Distribution in Central Paratethys.
Badenian (middle Miocene):
Vienna Basin
: Devínska Nová Ves (
Slovakia
).
Genus
Ebenomitra
Monterosato, 1917
Type
species.
Mitra ebenus
Lamarck, 1811
, subsequent designation by
Coan (1966: 130)
; Present-day, Mediterranean Sea.
Description.
“
Shell small, turriform or fusiform to widely fusiform. Protoconch bulbous, paucispiral, with about two glossy whorls. Teleoconch of up to 7.5 moderately or strongly convex whorls. Early spire whorls with strong ribs or very strong and wide folds; later whorls with strong wide folds vanishing below periphery of last adult whorl, or smooth; spiral sculpture not pronounced. Siphonal canal short to moderately long, sculptured with between two and four strong oblique cords. Aperture ovate to elongate, sometimes constricted towards siphonal canal; outer aperture lip lirate within. Inner apertural lip with three strong oblique columellar folds, adapicalmost fold strongest
” (
Fedosov
et al
., 2017: 601
).
Discussion.
Fedosov
et al.
2017
considered
Ebenomitra
as a subgenus of
Pusia
. The pros and cons of the usage of subgenera was controversially discussed in a plethora of papers (e.g.
Laurin 2010
;
Puillandre
et al.
2014
;
Teta 2018
and references therein). As stated in our previous contributions (Harzhauser & Landau 2016, 2019) we consider supraspecific classification levels as arbitrary and try to avoid the usage of subgenera. Therefore, we prefer to raise
Ebenomitra
to full genus rank.
Key to Paratethyan
Ebenomitra
species
:
1. Shell very broadly fusiform....................................................................
E. leucozona
-
Shell narrow fusiform.................................................................................. 2
2. Axial sculpture restricted to early teleoconch whorls........................................
E. pseudopyramidella
- Axial sculpture almost absent, suggestion of ribs on last whorl....................................
E. januszkiewiczi