Revision of northeast Pacific Paleogene cypraeoidean gastropods, including recognition of three new species: implications for paleobiogeographic distribution and faunal turnover
Author
Groves, Lindsey
Author
Squires, Richard L.
text
PaleoBios
2023
2023-08-10
40
10
1
52
http://dx.doi.org/10.5070/p9401057774
journal article
10.5070/P9401057774
0031-0298
10913295
11600574-2B0E-4C13-BC08-A3A5EF9EE562
BERNAYA KAYLINAE
SQUIRES AND GROVES
N. SP.
FIGS. 5D–F
Eocypraea castacensis
(
Stewart, 1926
[1927]).
Vokes, 1939
. p. 26 [in part], 154 [in part], pl. 20, fig.9 [not fig. 14, =
Eocypraea
(
Eocypraea
)
sp. cf.
E.
(
E.
)
inflata
(
Lamarck, 1802
)
of Groves, 2011].
Keen and Bentson, 1944
. p. 154 [in part].
Cypraea castacensis
Stewart, 1926
[1927].
Ingram, 1942
. p. 103 [in part], pl. 8, fig. 5 [not fig. 6, =
Eocypraea
(
Eocypraea
)
sp. cf.
E
. (
E.
)
inflata
(Lamarck)
of Groves, 2011].
Squires, 1984
. pp. 23, 24, fig. 7b.
Groves and Squires, 2021
. p. 226.
Zoobank ID —
LSID:
urn: lsid: zoobank. org:act:
62DE473E-1DF7-45C0-B34A-80197B354555
Diagnosis—
A
Bernaya
with medium-size shell, widest centrally, aperture moderately curving posteriorly, inner lip teeth moderately spaced and extending onto of left (columellar) side shell.
Holotype
and Type Locality—
LACMIP 40374.80
,
LACMIP
Type
14938 (
Figs. 5D–F
), length
25.6 mm
, width
17.3 mm
, height
12.9 mm
.
LACMIP
Locality
7242 [= LAC- MIP Locality 40374;
ex
CSUN
Locality 374], “Stewart bed,” middle part of
Llajas Formation
,
Las Llajas Canyon
, north side of
Simi Valley
,
Ventura County
, southern
California
.
Paratype
—
LACMIP 7242.7
,
LACMIP
Type 6523, length
25.7 mm
,width
17.2 mm
,height
14.1 mm
,
LACMIP
Locality 7242 [=
LACMIP
Locality 40374;
ex
CSUN
Local- ity 374]. This specimen was formerly hypotype
LACMIP 6523
(of
Squires, 1984
: pp. 23, 24, fig. 7b)
, of
Cypraea castacensis
Stewart, 1926
[1927] from the type locality (“Stewart bed,” Llajas Formation).
Referred Specimens—Hypotype
(of
Vokes, 1939
)
UCMP
33808,
UCMP
Locality 3296 (Llajas Formation, Devil Canyon, formerly referred to as Aliso Canyon).
One specimen
each from
LACMIP
Locality 7474 [
ex
CIT
Locality 559] (
LACMIP 7474.1
,
LACMIP
Type
14919),
LACMIP
Locality
11809 [
ex
CIT
Locality 215] (
LACMIP 11809.2
,
LACMIP
Type
14920),
LACMIP
Locality
22312 [
ex
UCLA
Locality 2312] (
LACMIP 22312.47
,
LACMIP
Type
14921), and
LACMIP
Locality
26619 [
ex
UCLA
Lo- cality 6619] (
LACMIP 26619.1
,
LACMIP
Type
14922), and
three topotypic specimens,
LACMIP 40374.81
,
LACMIP
Type
14939 (
LACMIP
Locality 72421 [=
LACMIP
Locality 40374;
ex
CSUN
Locality 374]), all
Llajas Formation
,
Simi Valley
,
Ventura County
, southern
California
.
Occurrence—
Upper lower Eocene, lower part of
“Domengine Stage”: “Stewart bed” north side of Simi Valley, and approximately
25 m
stratigraphically below “Stewart bed,” southwestern Santa Susana Mountains (Devil Canyon, [
ex
Aliso Canyon]), Ventura County, southern
California
. The depositional environment of the "Stewart bed" was revised by
Squires (2022)
as de- posited in a subtropical, shallow-marine environment at the distal edge of a braided delta.
Etymology—
Named for Kaylin Marie Solomon, grand- daughter of R.L. Squires (who collected the
holotype
,
paratype
, and three non-type specimens of this species).
Description—
Shell medium size, inflated, and smooth. Spire very low (normally covered by thin layer of shell). Aperture moderately straight (with moderate bend posteriorly), mostly narrow but widening signifi- cantly anteriorly into broad, concave depression. Outer lip with 18 to 19 teeth, confined to inner margin;most an- teriorly located teeth (four to five) strongest and extend half way up lip and are coincident with thinning of outer wall. Remaining outer lip teeth weaker and extend only short distance and are coincident with nearly vertical surface. Inner lip with 15 to 16 teeth, moderately spaced and becoming slightly more closely spaced posteriorly; strongest and longest inner lip teeth located on medial part of inner lip and extend to lip margin. Anterior end smooth, concave, and broad. Anterior terminal ridge well developed. Anterior (siphonal) and posterior (exhalant) canals well developed and prominent.
Remarks—
The ten known specimens of
Bernaya kaylinae
range in preservation from poor to good.
Bernaya kaylinae
differs from
Grovesia castacensis
by having a more inflated and non-tapered shell shape and much finer teeth.
Bernaya kaylinae
resembles a few specimens of
Grovesia mathewsonii
(
Gabb, 1869
)
that were original- ly identified as
Cypraea kerniana
Anderson and Hanna, 1925
from the Tejon Formation in Grapevine Creek, Kern County, southern
California
.
Bernaya kaylinae
differs from them by having a much less tapered teleoconch, a rounded (not lop-sided) last whorl, shorter transverse ribs on the venter, and less numerous and more closely spaced teeth on the outer lip.
Bernaya kaylinae
is very similar to
B. marcominii
Dolin and Aguerre (2016
: pl. 2, figs. 1–3), of middle Ypresian age in the Oise region of
France
.
Bernaya kaylinae
differs by having a narrower and more curved posterior ter- minal of the outer lip, slightly more projected posterior terminal of the inner lip, and a wider anterior end of the aperture.
Bernaya kaylinae
is also similar to
B. sixi
Pacaud and Robert (2016
: pl. 1, figs. 1, 2a, b), of middle Ypresian (Cuisian) age in the Oise region of
France
, in having a barely hidden spire. The new species differs from
B
.
sixi
by having coarser sculpture, a deeper notched posterior canal, a wide-concave depression at the anterior end of the shell, and no anterior terminal ridge.