Derilambrus cf. szaboi ( Müller, 1974 )

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 : 217

Derilambrus cf. szaboi ( Müller, 1974)

( Fig. 5B-E )

Parthenope szaboi Müller, 1974b: 277 , 283, pl. 1, figs 8-9; 1976b: 152, pl. 4, fig. 2; 1984: 74, pl. 53, fig. 5, pl. 54, figs 1-9.

Derilambrus szaboi – Hyžný & Dulai 2021: 190, 191, figs 72.1-10.

MATERIAL EXAMINED AND MEASUREMENTS (IN MM). — Three right propodi, ULB-IV-A (33): L = 14, H = 5.5, T = 3.5; ULB-IV-A (34): L = 15.5, H = 5.5, T = 4. — One left propodus ULB-IV-A (35): L = 13, H = 7.5, T = 6. — Two merus, ULB-IV-A (32): L = 9.5, H = 3, T = 4; ULB-IV-A (36): L = 16, H = 6, T =5.

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

DESCRIPTION

Propodus long, subtriangular in cross-section, acute edges; upper margin armed with acute spines irregularly placed; lower margin bearing a continue row of granules or spines; outer margin with a transverse row of continuous acute spines; inner margin coarse granulate, with a medial row of granules; index short, obliquely downward directed. Merus elongate, subrhomboidal in section, lateral angles coarsely spiny.

REMARKS

The ‘Faluns’ parthenopid chelae are reminiscent of those attributed to Derilambrus szaboi, from several localities of the middle Miocene of Hungary (see Müller 1984: pl. 54, figs 6-9; Hyžný & Dulai 2021: fig. 72.7-10), and in lesser extend of those of Parthenopoides tetenyensis ( Müller, 1984), which are shorter than the former species ( Müller 1984: 74-75, pl. 66, fig. 3; Hyžný & Dulai 2021: fig. 71.6-15). The ‘Faluns’ chelae have been found isolated, and no carapace attributable to Parthenopidae has been recovered in those outcrops to date, and moreover, it’s hard to assign an isolated chela to a carapace of any particular species. However, despite the poor degree of preservation of the ‘Faluns’ parthenopid chelae, which are strongly reworked, they still preserve some main characters that allow to check the similarities with the chelae described as Derilambrus szaboi, to which, they are assigned tentatively.

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.