Undetermined

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 : 212

Undetermined chela ( Fig. 3C-F)

MATERIAL EXAMINED AND MEASUREMENTS (IN MM). — Fragment of left chela preserving part of palm and index, ULB-IV-A (15): L = 8; H = 4; T = 3.

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

DESCRIPTION

Portion of palm preserved covered by coarse rounded granules, becoming squamous near the index; outer and inner margins slightly convex. Index slender, strongly curved upwards, slightly curved inwards, covered by squamous rounded granules; occlusal margin with acute cutting edge, not toothed.

REMARKS

The slender and curved left index does not match with that of the squat lobster, usually spinose, neither with that of the porcellanids, such as the typical Miocene species of Petrolisthes, wich have more robust and straighter index (cf. Górka 2018: text-fig. 3, 4a-b, 6, 7, 8a-b). Notwithstanding, some extant species of Pisidia Leach, 1920, possesses pollex of left chela somewhat slender and curved. Lacking of complete specimens, we place this chela within Porcellanidae with reservations.

Figures

FIG. 3. — Decapods from the ‘Savignean facies’ (Langhian) of the ‘Blandinerie’ quarry, Breil (Maine-et-Loire): A, B, Galathea weinfurteri Bachmayer, 1950, ULB- IV-A (9): A, dorsal view; B, frontal view; C-F undetermined?porcellanid; G-K, Paguristes gagnaisoni Gagnaison, 2012: G, ULB-IV-A (19), right chela; H, ULB-IV-A (19.2), right chela outer margin; I, occlusal margin; J, ULB-IV-A (17), right chela inner margin; K, right chela outer margin; L-Q, undetermined paguroid: L, ULB- IV-A (49), right dactylus outer margin; M, occlusal margin; N, inner margin; O, ULB-IV-A (44), left index, inner margin; P, occlusal margin; Q, outer margin. Scale bars: A-J, 5 mm; L-Q, 10 mm. Photographs by À. Ossó.