A revision of the Australian fossil species of Zoila (Gastropoda: Cypraeidae)
Author
Darragh, Thomas A.
text
Memoirs of Museum Victoria
2011
2011-12-31
68
1
28
https://museumsvictoria.com.au/collections-research/journals/memoirs-of-museum-victoria/volume-68-2011/pages-1-28/
journal article
10.24199/j.mmv.2011.68.01
1447-2554
10665999
Zoila didymorhyncha
sp. nov.
Figures 1E
,
6A–E, I
Description
. Shell solid, small for genus, elongate, subfusiform; base relatively flat, but rounded on either side of aperture. Spire not visible. Posterior canal long, with rounded sides, sunk into massive rounded posterior rostrum formed by extensions of inner and outer lips. Anterior canal long, with rounded sides, sunk into a thick, rather flat rostrum. Aperture somewhat sinuous; outer lip with 10–24 well-developed teeth extending along entire lip; teeth completely obsolete on
one specimen
. Columella lip with 3–26 well-developed teeth extending along entire lip on most specimens; teeth obsolete on
one specimen
. Fossula moderately developed, very shallow, bounded anteriorly by a small, weak, terminal ridge.
Dimensions
.
Type
locality
.
PL3022
cliff section at
Addiscot Beach
, beds
Bl
09–l07, southwest of small gully, clay overlying
Demons Bluff Formation
,
Victoria
.
AMG
Torquay BT
6l9490.
Jan Juc Formation. Early Janjukian
.
Type material
.
Holotype
P302687, collected
T
.
A. Darragh
,
4 December 1985
;
paratype
P302685, collected
T
.
A. Darragh
8 May 1990
.
Time range
. Early Janjukian, Late Oligocene.
Occurrence and material
.
PL3022
Addiscott Beach (
three specimens
)
.
Figure 3. A–G,
Cypraeorbis ventripotens
Moodys Branch Formation
, late Eocene, Town Creek, Jackson, Mississippi, United States of America; A–C, × 2; F, × 4; D–E, G, × 2; H–J, N,
Cypraeorbis arlettae
MNHN, Chipola Formation, Burdigalian
, early Miocene, Farley Creek, Calhoun County, Florida, USA; K, O,
Cypraeorbis wilcoxi
MNHN, Chipola Formation, Burdigalian
, early Miocene, Farley Creek, Calhoun County, Florida, United States of America; L–M,
Barycypraea zietsmani
Liltved and Le Roux, 1988
, P31664, Alexandria Formation, late Neogene, Eastern Cape, South Africa, × 1.
Figure 4. A–F,
Cypraeorbis medius
MNHN, Bartonian
, late Eocene, Bois du Rois, Auvers sur Oise, France; A–C, D–E, × 1.5; F, × 2.
Remarks
. The small size and the massive development of the anterior and posterior rostra separate this species from all others in the genus. In morphology, it comes closest to
Zoila mulderi
(Tate)
, but it has a massive anterior rostrum lacking in
Z. mulderi
and the posterior rostrum is not notched as it is in
Z. mulderi
.
Etymology.
Greek, didymos, double; rhynchos, snout.