Review of the Late Jurassic erymoid lobsters (Crustacea: Decapoda)
Author
Devillez, Julien
Muséum national d’Histoire naturelle, Paris Centre de Recherche en Paléontologie – Paris (CR 2 P, UMR 7207), Sorbonne Université, MNHN, UPMC, CNRS, 57 rue Cuvier, F- 75231 Parix cedex 05 Paris (France)
julien.devillez@edu.mnhn.fr
Author
Charbonnier, Sylvain
Muséum national d’Histoire naturelle, Paris Centre de Recherche en Paléontologie – Paris (CR 2 P, UMR 7207), Sorbonne Université, MNHN, UPMC, CNRS, 57 rue Cuvier, F- 75231 Parix cedex 05 Paris (France)
sylvain.charbonnier@mnhn.fr
text
Geodiversitas
2021
2021-01-28
43
2
25
73
journal article
10.5252/geodiversitas2021v43a2
a2545208-1888-44e9-82d3-b429219cd070
1638-9395
4486479
urn:lsid:zoobank.org:pub:6EF0DFAC-609D-407D-B4CC-CB985C3295FC
Eryma lerasi
(
Étallon, 1861
)
(
Fig. 6
)
Macrourites lerasi
Étallon, 1861: 170
, pl. 1, fig. 6.
Eryma dutertrei
Sauvage, 1891: 91
, pl. 4, figs 7-12.
—
Van Straelen 1925: 270
, fig. 126.
—
Moret 1946: 51
, fig. 2.
—
Secrétan 1964: 69
.
—
Förster 1966: 117
, fig. 20, pl. 16, figs 6-7.
—
Carriol 1991: 223
.
—
Feldmann & Titus 2006: 63
.
—
Schweitzer
et al.
2010: 23
.
n. syn.
Eryma gracilimana
Lahusen, 1894: 320
, pl. 1, fig. 9.
—
Van Straelen 1925: 272
.
—
Glaessner 1929: 155
.
—
Gerasimov 1955: 25
, pl. 8, fig. 8.
—
Birshtein 1956: 75
.
—
Förster 1966: 122
.
—
Gerasimov
et al.
1995: 10
, 30.
—
Ilyin 2000: 152
, 154, table 1.
—
Feldmann & Titus 2006: 63
.
n. syn.
Eryma portlandica
Woods, 1930: 79
, pl. 22, figs 2-4.
—
Secrétan 1964: 69
.
n. syn.
Eryma lerasi
–
Van Straelen 1925: 276
.
—
Glaessner 1929: 155
.
—
Schweitzer
et al.
2010: 24
.
Clytia dutertrei
–
Glaessner 1929:115
.
Eryma bedelta
(pars.) –
Förster 1966: 99
.
Eryma gracilimanum
–
Schweitzer
et al.
2010: 24
.
TYPE MATERIAL. —
Holotype
lost (
Förster 1966
).
TYPE LOCALITY. — Haut-Rhin departement, Alsace-Lorraine,
France
.
TYPE AGE. — Not precised in original publication. However, considering the specimens that could be assigned to
E. lerasi
(see discussion below), all from Late Jurassic deposits, and the absence of sediments corresponding to the end of the Kimmeridgian-Tithonian in Haut-Rhin department (
Skrzypek
et al.
2008
), it is reasonable to consider that the lost
holotype
was probably found in Late Jurassic deposits (Oxfordian-Kimmeridgian).
DESCRIPTION
Carapace
Sub-cylindrical carapace; very narrow post-orbital area; deep and wide cervical groove, curved dorsally, subvertical ventrally, joined to dorsal margin and to antennal groove; deep antennal groove; short, deep gastro-orbital groove, originating as a median inflexion of cervical groove; deep postcervical groove, slightly curved, joined to dorsal margin and to branchiocardiac groove; deep and narrow branchiocardiac groove, subparallel to postcervial groove, inflected towards its junction to hepatic groove, strongly inclined, joined to dorsal margin and to hepatic groove; deep and narrow hepatic groove, concavo-convex, joined to cervical groove; flat ω and χ areas; deep and wide inferior groove.
FIG. 6. —
Eryma lerasi
(
Étallon, 1861
)
:
A
, original figure of
Étallon (1861
: pl. 1, fig. 6) of the holotype (Haut-Rhin, France);
B
, original figure of
Lahusen (1894
: pl. 1, fig. 9) of the holotype of
Eryma gracilimanum
(Tithonian, Mnevniki, Russia);
C-E
, original figures of
Sauvage (1891
: pl. 4, figs 7-8, 10) of syntypes of
Eryma dutertrei
(Kimmeridgian,Boulogne-sur-Mer,France);
F
, specimen NHMUK 2045 (Kimmeridgian,Portland,United Kingdom);
G -J
, syntypes of
Eryma portlandica
Woods,1930
(Tithonian,United Kingdom): NHMUK In.27136 from Weymouth (
G
), In.27141 from Portland (
H
), NHMUK I.2835 from Preston (
I
), NHMUK In.27140 from Portland (
J
);
K
,
L
, specimen NHMUK I.7494 (Kimmeridgian,Weymouth,United Kingdom).Abbreviations:
a
, branchiocardiac groove;
b
, antennal groove;
b
1
, hepatic groove;
c
, postcervical groove;
d
, gastro-orbital groove;
e
1
e
, cervical groove;
i
, inferior groove;
PoA
, post-orbital area.Photographs and line drawing: J. Devillez. Scale bars: 1 cm.
Thoracic appendages
Chelate P1; P1 propodus subrectangular, wide, strongly compressed dorso-ventrally; narrow dactylar bulge, slightly inflated, posteriorly delimited by a groove; thin, elongated fingers, equal in length, almost straight or slightly curved inward; occlusal margins with short and widely spaced conical teeth; P1 carpus short, subtriangular; elongated P1 merus.
Ornamentation
Carapace with a heterogeneous ornamentation; carapace covered by small rounded tubercles preceded by crescentshaped depressions, depressions wider and deeper in branchial region; P1 propodus, fingers and carpus densely covered by small tubercles preceded by shallow depressions.
DISCUSSION
Macrourites lerasi
Étallon, 1861
was described on a P1 chela currently lost. It was assigned to
Eryma
by
Van Straelen (1925)
. This assignation is supported by the subrectangular propodus, compressed dorso-ventrally, with elongated thin fingers curved inward, and a narrow dactylar bulge. Later,
Förster (1966)
integrated
Eryma lerasi
into the synonymy of
Eryma bedeltum
(Quenstedt, 1857)
. This synonymy is not maintained here because the P1 fingers of
E. lerasi
are thinner and its P1 propodus is clearly subrectangular and not trapezoidal.
The shape of the propodus, its fine and dense ornamentation, its thin fingers, their slight curvature and the narrow dactylar bulge are morphological features that
E. lerasi
shares with
Eryma portlandica
Woods, 1930
(Tithonian,
United Kingdom
;
Fig. 6
G-J). So,
E. portlandica
is here considered as a junior synonym of
E. lerasi
. The illustration of
Eryma gracilimanum
Lahusen, 1894
(Tithonian,
Russia
;
Fig. 6B
), an isolated P1 chela, exhibits the same morphological features. So, this species is also considered here as a junior synonym of
E. lerasi
. Contary to
E. lerasi
and
E. gracilimanum
, the
type
material of
E. portlandica
includes carapaces.
Eryma dutertrei
Sauvage, 1891
(Kimmeridgian,
France
;
Fig. 6
C-E) and the carapace identified as
Eryma
cf.
boloniensis
Sauvage, 1891
(Kimmeridgian,
United Kingdom
;
Fig. 6K, L
) by
Förster (1966)
share similar characteristics: the cervical groove is strongly inflected at carapace mid-height and curved dorsally, the junction between the postcervical and branchiocardiac grooves is low on the carapace, the ornamentation is dense, made of tubercles separated by well-marked depressions. So, we also add
E. dutertrei
and the specimen of
E.
cf.
boloniensis
of
Förster (1966)
within the synonymy of
E. lerasi
.
The carapace groove pattern of
E. lerasi
exhibits some characteristics distincts from other species of the genus. Indeed, the junction between the postcervical and branchiocardiac grooves is clearly lower than in
E. georgeii
,
E. jungostrix
,
E. mandelslohi
,
E. modestiforme
,
E. ventrosum
, and
E. westphali
. There is no ventral extension of the postcervical groove in
E. lerasi
contrary to
E. georgeii
,
E. jungostrix
,
E. mandelslohi
,
E. modestiforme
,
E. ventrosum
, and
E. westphali
. The morphology of the P1 chelae of
E. lerasi
are thinner than that of
E. georgeii
,
E. major
,
E. veltheimii
, and
E. westphali
. Finally, the ornamentation of
E. lerasi
, made of tubercles and depressions, differs from that of
E. jungostrix
,
E. major
,
E. mandelslohi
, and
E. veltheimii
, covered only by tubercles or depressions.