New records of Palaeocorystoidea from the Iberian Peninsula and remarks on the taxonomic significance of the posterior margin of Cenomanocarcinus Van Straelen, 1936 and Hasaracancer Jux, 1971 (Decapoda; Brachyura; Cenomanocarcinidae)
Author
Ossó, Àlex
text
Zootaxa
2017
4303
2
273
283
journal article
32522
10.11646/zootaxa.4303.2.7
2a5c89e9-de41-47fc-8d38-c1a10ae82c41
1175-5326
840956
99DB2319-498E-4A8B-BE10-12B53E2B7C9A
Cenomanocarcinus
sp. 1
(
Fig. 2
)
Cenomanocarcinus
sp.
Ossó
et al.
2015
: 241
, t. 1.
FIGURE 2.
Cenomanocarcinus
sp. (
sp. 1
), From
tardefurcata
Biozone
of Escucha Formation, early Albian. Traiguera (Castelló, Spain). MGB 78174, dorsal view of carapace. Abbreviations: ebs, epibranchial spines; pebs, post-epibranchial spine. Scale bar equal to 10 mm.
Locality and horizon.
Traiguera (Baix Maestrat, Castelló, Spain),
Leymeriella tardefurcata
Biozone, Escucha Formation
, early Albian.
Material examined and measurements (in mm).
One incomplete specimen embedded within siliciclastic matrix, MGB 78174: width (from the basis of epibranchial spine) = 50 (
25x2
).
Description.
Relatively large carapace, wider than long, cuticle smooth, appears to be subhexagonal, bearing three longitudinal ridges, one axial composed by the meso-, meta- and urogastric tubercles and the cardiac tubercle, and two branchial ridges. Orbito-frontal, anterolateral and posterior margin not preserved. Epibranchial spine subtriangular, strong, appears to be long. Posterolateral margin slightly concave, weakly rounded in cross section, post-epibranchial spine subtriangular, acute. Protogastric region swollen, two rounded tubercles aligned transversally; meso- and metagastric region defined by elongated tubercles, forming the axial ridge, slightly depressed by the cervical groove; urogastric region ridged longitudinally. Cardiac region narrow, ridged elongated. Intestinal region flattened, depressed. Hepatic region not completely preserved. Epibranchial region with a weak sigmoidal ridge that starts with a strong tubercle and ends at the level of last anterolateral tooth (epibranchial spine); two small tubercles at mid-length. Mesobranchial region defined by a coarse longitudinal ridge with blunt edges, depressed posteriorly and ending in a prominent broken spine. Metabranchial region depressed. Shallow branchiocardiac groove.
Remarks.
The general appearance of the Traiguera specimen of
Cenomanocarcinus
, falls into the first morphological group reported by
Ossó
et al.
(2015
: 241) by its coarse and parallel branchial ridges. In particular, it recalls in many aspects his coeval
C. cantabricus
from the Albian of
Cantabria
(
Spain
) and the Cenomanian
C. boedekeri
from the
Cenomanian of Texas
(USA), in having coarse axial and branchial ridges, presence of a postepibranchial tooth, similar pattern of epibranchial ridge and possibly a long epibranchial tooth. Nevertheless, the Traiguera specimen is incompletely preserved and lacks diagnostic characters such as: fronto-orbital, anterolateral, and posterior margins. The absence of those features impedes a specific assignation of this specimen or if it had been the case, the proposal of a new species for it.