indeterminate

Ossó, Àlex, Gagnaison, Cyril & Gain, Olivier, 2022, A re-appraisal of the middle-late Miocene fossil decapod crustaceans of the ‘ Faluns’ (Anjou-Touraine, France), Geodiversitas 44 (6), pp. 207-228 : 216-217

Family and genus indeterminate

( Fig. 5A )

MATERIAL EXAMINED AND MEASUREMENTS (in mm). — Remains of a central portion of dorsal carapace, ULB-IV-A (26): L = 10; W = 13.

LOCALITY AND HORIZON. — ‘Blandinerie’ quarry, Breil (Maine-et-Loire). ‘Savignean facies’, Langhian (middle Miocene).

DESCRIPTION

Central portion of dorsal carapace, strongly vaulted, regions defined by inflations with tubercles and coarse granules, well divided by grooves. Mesogastric region with posterior portion subpentagonal bearing a large and prominent granulate tubercle, anterior portion elongate and narrow, bearing a tubercle medially. Protogastric lobe swollen posteriorly, with scattered coarse granules and small tubercles. Urogastric region depressed, defined by two transverse rows of rounded granules, two the anterior one and four the posterior one. Cardiac region large, swollen, with large rounded granules. Epibranchial lobes well differentiated, prominent, with coarse granules and small tubercles, obliquely directed to the anterolateral margin. Cervical and branchiocardiac grooves well marked, smooth, the latter the deeper.

REMARKS

It’s difficult to assign this fragmentary remain to a known fossil crab. Nonetheless,its regions conformation is reminiscent of majids, in particular the ornamentation and the strong constrictions at the urogastric-cardiac level. For instance, it strongly recalls Micippa hungarica Lőrenthey in Lőrenthey & Beurlen, 1929 (cf. Müller 1984: pl. 52, figs 4-6, pl. 53, figs 1-4; Hyžný & Dulai 2021: fig. 67.1-6). However, the absence of other carapace portions, prevent us from assigning this remain to any genera or family. or family. Thus, we place it within Majoidea , with reservations.

Figures

FIG. 5. — Decapods from the ‘Savignean facies’ (Langhian) of the ‘Blandinerie’ quarry,Breil (Maine-et-Loire):A, indeterminate majoid,ULB-IV-A (26): dorsal view;B-E, Derilambrus cf.szaboi (Müller,1974):B, ULB-IV-A (33),right propodus,outer margin;C, inner margin;D, ULB-IV-A (35),right propodus,outer margin;E, right propodus, inner margin;F-K, Pilumnus mediterraneus (Lőrenthey, 1897):F, ULB-IV-A (14),dorsal view;G, frontal view;H, ULB-IV-A (18),dorsal view;I, frontal view;J, ULB-IV-A (20), left chela,outer margin;K, inner margin;L-M, undeterminated Carcinidae:L, ULB-IV-A (52),right chela;M, ULB-IV-A (50) left chela;N-Q, Liocarcinus kuehni (Bachmayer, 1953a):N, ULB-IV-A (10),dorsal view;O, frontal view;P, ULB-IV-A (13), dorsal view;Q, frontal view.Scale bars:A-I, N-Q, 5 mm;J-M, 10 mm. Photographs by À. Ossó.