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 westphali
Schweigert, Dietl & Röper, 2000
(
Fig. 7
G-J)
Eryma westphali
Schweigert, Dietl & Röper, 2000: 6
, pl. 3, figs 1-3.
—
Dietl & Schweigert 2001: 53
, 110, fig. 85.
—
Garassino & Schweigert 2006: 8
.
—
Feldmann & Titus 2006: 64
.
Galicia westphali
–
Schweitzer
et al.
2010: 25
.
—
Hyžný
et al.
2015: 375
.
TYPE MATERIAL. —
Holotype
SMNS 24227
. TYPE LOCALITY. —
Nusplingen
,
Baden-Württemberg
,
Germany
. TYPE AGE. —
Kimmeridgian
.
DESCRIPTION
Carapace
Short, spiny rostrum; fusiform intercalated plate; deep, wide cervical groove, joined to dorsal margin and to antennal groove; deep antennal groove; short, sub-horizontal gastroorbital groove; postcervical groove slightly curved forward, not joined to dorsal margin, joined to branchiocardiac groove at carapace mid-height, with a short ventral extension; branchiocardiac groove dorsally deep, narrowing in its ventral part, not joined to dorsal margin, joined to hepatic groove; hepatic groove concavo-convex.
Pleon and uropods
Somites with subtriangular pleurites, with a bulge on their basis; wide rounded uropods; uropodal endopods with a longitudinal carina; uropodal exopods with a small spine on external margin.
Thoracic appendages
Chelate P1; P1 propodus subrectangular, narrow and strongly elongated; P1 fingers shorter than propodus, slender, almost
FIG. 7. —
Eryma major
Oppel, 1861
,
Eryma veltheimii
(
Münster, 1839
)
and
Eryma westphali
Schweigert, Dietl & Röper, 2000
from the Kimmeridgian of Germany:
A
, holotype SMNS 3682 of
E. major
from Egesheimer;
B
, specimen SMNS 67655 of
E. major
from Gerhausen;
C
, specimen SMNS 64371 of
E. major
from Nusplingen;
D -F
, holotype BSPG AS VII 186 of
E. veltheimii
from Kehlheim: part (
D
), counter-part (
E
), details of telson and uropods (
F
);
G -J
, holotype SMNS 24227 of
E. westphali
from Nusplingen: general view (
G
), schema of the carapace (
H
), schema of left chela (
I
), schema of right chela (
J
);
C
, specimen SMNS 63733 from Nusplingen. Abbreviations:
a
, branchiocardiac;
as
, antennal spine;
b
, antennal groove;
b
1
, hepatic groove;
c
, postcervical;
d
, gastro-orbital groove;
e
1
e
, cervical groove;
ip
, intercalated plate. Black arrows show the spines. Photographs and line drawings: J. Devillez. Scale bars: 1 cm.
straight or slightly curved inward, with a terminal hook; occlusal margin without teeth; P1 carpus short, subtriangular; thin P2-P5; P2-P3 chelate.
Ornamentation
Carapace with a dense, heterogeneous ornamentation; gastric and cardiac regions covered by tubercles; antennal, hepatic, and branchial regions covered by small rounded depressions; presence of an orbital spine; tergites and pleurites densely covered by small rounded depressions; presence of a strong antennal spine; smooth P1-P5.
DISCUSSION
This species is only known by three specimens. It is assigned to
Eryma
because of its typical carapace groove pattern (short gastro-orbital groove, postcervical and branchiocardiac grooves joined at carapace mid-height, hepatic groove concavo-convex) and the shape of the P1 chelae (elongated propodus, subrectangular, with slender fingers progressively narrowing to their distal extremity).
Among the erymid lobsters,
Eryma westphali
is the only species with heterochelous P1 chelae on a same specimen. Left propodus is more elongated and narrower than the right one, and the left fingers are straight and short while the right ones are curved and slightly longer (
Fig. 7I, J
). The strongly elongated and narrow P1 propodus with relatively short fingers of
E. westphali
is characteristic of the species. Only
Eryma veltheimii
(
Münster, 1839
)
have P1 with a very long propodus, but it is clearly wider.
In
E. westphali
the branchial region is dorsally shorter than in
E. georgeii
,
E. jungostrix
,
E. lerasi
,
E. modestiforme
, and
E. ventrosum
. Contrary to
E. lerasi
and
E. quadriverrucatum
,
E. westphali
exhibits a ventral extension of the postcervical groove. Moreover, the dichotomy of the ornamentation of the carapace between the gastric and cardiac regions, covered by tubercles, and the remaining regions of
E. westphali
, covered by small depressions, is unique among the genus.