Volutidae (Mollusca: Gastropoda) of the Lakhra Formation (Earliest Eocene, Sindh, Pakistan): systematics, biostratigraphy and paleobiogeography
Author
Merle, Didier
Author
Pacaud, Jean-Michel
Author
Métais, Grégoire
Author
Bartolini, Annachiara
Author
Lashari, Rafiq A.
Author
Brohi, Imdad A.
Author
Solangi, Sarfraz H.
Author
Marivaux, Laurent
Author
Welcomme, Jean-Loup
text
Zootaxa
2014
3826
1
101
138
journal article
45364
10.11646/zootaxa.3826.1.3
6f4b1535-6c6b-4446-aa26-b1ba83ad9126
1175-5326
228537
53549D58-8F38-47B5-879F-0245E900C131
Lyria
sp.
(
Fig. 4A
)
Description.
Fragment of a narrow spire, H 14.8, D 9.0 mm. Protoconch eroded, probably paucispiral. Teleoconch of four whorls, the last broken. Whorls high, weakly convex, delineated by a deep, linear suture. Axial sculpture of strong but narrowly rounded costae, almost corresponding from whorl to whorl. No spiral sculpture. Costae opisthocline, rather straight. Columella with at least three folds.
Material.
1 spm (stn 5:
CPAG
.RAN.
I.1
, cast
MNHN
.F.
A50339
).
Comments.
Although the aperture of this specimen is lacking, the shape of its teleoconch whorls is similar to those found in other members of
Lyria
, as for example in
Lyria subturgidula
(d’Orbigny, 1850)
from the Middle Eocene of the Paris Basin. By its high whorls and its straight costae, this specimen is easily distinguishable from
Lyria cossmanni
Vredenburg, 1923
(=?
L. feddeni
Vredenburg, 1923
) from the Lakhra Formation and from
Lyria samanaensis
Cox, 1930
from the Hangu Formation (Samana Range, North
Pakistan
). Both species belong to another genus,
Lyriopsis
nov. gen., described below.
Stratigraphic range.
Lakhra Formation: Lakhra Dome.