A revision of the Australian fossil species of Zoila (Gastropoda: Cypraeidae)AuthorDarragh, Thomas A.Museum Victoria, GPO Box 666, Melbourne, Victoria 3001, Australiatdarragh@museum.vic.gov.autextMemoirs of Museum Victoria20112011-12-3168128https://museumsvictoria.com.au/collections-research/journals/memoirs-of-museum-victoria/volume-68-2011/pages-1-28/journal article10.24199/j.mmv.2011.68.011447-255410665999Zoila platypyga
(
McCoy, 1876
)
Figures 2A
,
11A–H
,
12A–G
,
13A–CCypraea (Aricia) platypygaMcCoy, 1876
, p. 39
, fig. 1-1c.
Cypraea (Aricia) consobrinaMcCoy, 1877
, p. 36
, pl. 49, fig. 2.
Cypraea toxorhynchaTate, 1890
, p. 210
.—
Tate, 1892
, p. 5
, fig. 6; pl. 6, fig. 5.
Cypraea platypyga
McCoy.
—
Tate, 1890
, p. 211
.
Cypraea (Erosaria) platypyga
McCoy.
—
Harris, 1897
, p. 209
.
Gisortia platypyga
(McCoy)
.—
Vredenburg, 1927
, p. 43
.
Gisortia consobrina
(McCoy)
.—
Vredenburg, 1927
, p. 43
.
Zoila (Zoila) platypyga platypyga
(McCoy)
. —
Schilder, 1935
, p. 338
.
Zoila (Zoila) platypyga simpliciorSchilder, 1935
, p. 338
.
Zoila (Zoila) consobrina
(McCoy)
.—
Schilder, 1935
, p. 338
.
Zoila (Zoila) toxorhyncha
(Tate)
.—
Schilder, 1935
, p. 338
.
Zoila platygyra
[
sic
] (McCoy). —
Wilson and Clarkson, 2004:51
,
pl. 52, pl 53 (
toxorhyncha
) form.
Zoila consobrina
(McCoy)
. —
Wilson and Clarkson, 2004:51
, pl. 54.
Description
. Shell of five to six whorls, solid, of medium size for genus, globose to subpyriform, last whorl covered with glaze, enveloping the previous whorls, somewhat humped posteriorly with posterior dorsal slope steeper than anterior; smooth dorsal surface. Spire slightly projecting, of 4–5 whorls, covered with thick callus on most specimens. Protoconch smooth, of one whorl merging imperceptibly with teleoconch whorls; beginning of protoconch slightly immersed. Posterior canal with rounded sides, wide, notched, projecting posteriorly on most specimens with prominent solid lateral projections, longer on columellar side. Anterior canal subcylindrical, narrow, deeply incised, reflexed dorsally and supported by thick lateral flanges on most specimens; on large specimens canal considerably extended.Aperture narrow, very slightly curved, slightly wider and steeply sloping inwards at anterior end before anterior canal; outer lip with 24–33 well-developed teeth extending along entire lip. Columella with 24–33 strongly developed ridges, extending along entire columella, bifurcating on some specimens, not extending onto fossula. Fossula well developed, concave, broad and spoon-shaped, bounded anteriorly by well-developed single terminal ridge.
Dimensions
.
L
W
H
LT
CT
Holotype P12137
77
49
42
24
27
P12134
67
43
37
30
28 holotype of
consobrina
T823
94
47
42
28
26 holotype of
toxorhyncha
Figured specimen P304414
100
54
51
33
33
Figured specimen P304415
82
50
41
30
30
Figured specimen P14594
100
53
51
33
26
Type locality
. ‘Tertiary clays of shore near foot of Mount Eliza’.
Type material
.
Holotype
P12137, collected
Geological Survey
of
Victoria
.
Holotype
of
Cypraea (Aricia) consobrina
P12134,
Moorabool River
.
Holotype
of
Cypraea toxorhynchaTate, 1890
,
SAMT832
,
Muddy Creek
,
Ralph Tate
collection
.
Holotype
of
Zoila (Z.) platypyga simpliciorSchilder, 1935
,
BM
(NH),
Muddy Creek
, E.O. Teale collection (specimen missing). Figured specimen P304414,
F.A. Cudmore
collection, collected 1941.
Figured
specimen P304415, presented Mr J.
T
. Cunningham,
22 February 1966
. Figured specimen P14954, collected
F.A. Cudmore
,
February 1932
.
Time range
. Balcombian–Bairnsdalian, Middle Miocene.
Occurrence and material
.
Balcombian. Muddy Creek
Formation:
Muddy Creek
(P14639, P61587, P304426, P308692-4, P308696, P308748, P308798, P308796,
21 specimens
);
PL3082Clifton Bank
(P58641, P304419, P304434, P304446, P308691, P308695, P308697,
16 specimens
)
.
Gellibrand Formation
:
Gellibrand River
(P304424, P304448, P308734,
four specimens
)
;
northwest of
Princetown
(P304441,
one specimen
)
;
Princetown
(P5347,
one specimen
);
PL3060
dam on lot 393 (P304429,
one specimen
)
;
4 km
north of
Port Campbell
(P304439,
one specimen
)
;
between
Pt. Ronald
and
Gibsons Beach
(P304444,
one specimen
)
;
Cowley Creek
(P304438,
one specimen
)
;
dam at
Clyne’s
house (P308698,
one specimen
)
;
north of
Port Campbell
(P308699,
one specimen
)
;
Curdies
(P59228,
one specimen
);
PL3068
southwest end of Gibson Beach (P304443,
one specimen
)
.
Fyansford Formation
:
PL3078Fossil Beach
(P304427-8, P304437, P304415, ten specimens);
Balcombe Bay
(P308751-3,
three specimens
)
; Schnapper Point (P308755,
two specimens
); Braeside Tunnel (P30445,
one specimen
); Campbells Point (P304436,
one specimen
);
PL3069Red Bluff
,
Shelford
(P304435,
one specimen
)
; Shelford (P304420,
one specimen
); Overburden, Batesford Limestone Quarry (P308811, P309021-3, P310316, P310313,
six specimens
).
Cadell Marl:
PL3084
south of
Morgan
,
South Australia
(P304430,
one specimen
)
.
BairnsdalianFyansford Formation
:
Grices Creek
(P14594, P304425,
five specimens
);
PL3103
downstream
Grices Creek
(P308754,
one specimen
)
;
Grices Creek
, middle beds (P304414,
one specimen
);
PL3100
Murgheboluc 4A (P308735,
one specimen
)
.
Remarks
. The
holotype
of
Cypraea consobrina
McCoy
is a slightly immature, water-worn specimen found in the Moorabool River near Geelong, washed out of the Fyansford Formation. The posterior and anterior canals are not so highly callused, even when allowing for wear, as typical specimens of
Z. platypyga
. However, these forms intergrade and it is synonymised with the latter.
The
holotype
of
Cypreaeatoxorhyncha
Tate
is a large specimen, with the extensions of the posterior canal very well developed. The anterior canal is very long and reflexed dorsally. Similar specimens are associated with and intergrade with typical
Z. platypyga
specimens in the Muddy Creek Formation and the Fyansford Formation. This name is also synonymised with
Zoila platypyga
. The
holotype
of
Zoila (Zoila) platypyga simpliciorSchilder, 1935
, said to be in the Teale collection, Natural History Museum, London, cannot be located. Schilder indicated that it came from Muddy Creek and that it differed from
Z. platypygasensu stricto
by having less produced and less rounded extremities, less developed lateral flanges and a less projecting spire. The posterior extremity was bent to the left.These differences in callus development are minor intraspecific variations, as the specimens illustrated in figs. 11–13 show. Schilder stated that it bore a resemblance to
Z. consobrina
and that it came from a younger horizon than the latter. In fact, the
holotype
of
consobrina
comes from the same stratigraphical horizon.