Dhondtichlamys sarumensis (H. Woods, 1902)
WOODS, H. 1899-1903. A monograph of the Cretaceus Lamellibranchia of England. Vol. I: 1-232, pls. 1-42. Paleontological Society Monograph. The Paleontographical Society. [p. 192, pl. 37, figs. 1, 2a-b, 3]
1902 Pecten (Aequipecten) sarumensis H. Woods, 1902
H. Woods, 1899-1903, plate 37.
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«Description.—Shell small, slightly inequilateral, height ami length nearly equal, outline rounded, convexity small. Apical angle 107° to 111°. Ears rather large.
Right valve ornamented with very numerous (fifty to sixty) narrow, well-marked, radial ribs, which are separated by deep, narrow grooves. The ribs are often slightly unequal, sometimes alternately, the smaller ribs being introduced later than the larger. The ribs bear numerous small, similar, spiny scales, placed either vertically or sloping, and sometimes having a roughly concentric arrangement; near the umbo concentric lamellae occur. Postero-dorsal margin with fine oblique striae. Anterior ear long, with a deep sinus and four radial ribs with spines. Posterior ear much shorter, with three or four radial, spiny ribs. Left valve not seen.
(1—4) A. quadratus zone, East Harnham, Salisbury
Affinities.— In form this species resembles P. campaniensis, but is easely distinguished by the much larger number of ribs. The ornamentation resembles that of P. pexatus, but the shell is without radial folds, the ribs are fewer, and the apical angle larger. Radial folds occur on even the smallest specimens of P. pexatus.
Types.— In Dr. Blackmore's collection. Distribution. — A. quadratus zone of East Harnham (Salisbury). B. mucronata zone of Clarendon (Salisbury).» HENRY WOODS, 1902
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«Description. Small species with numerous (45-65) spiny, scaled ribs and relatively large auricles.
Remarks. Distinguished from other species by the large number of dividing ribs and the concentric spiny scales on these ribs. M. arlesiensis (Cenomanian) is larger and its ribs do not divide; M. campaniensis (Coniacian-Maastrichtian) has fewer ribs and lacks scaly ornament. Occurrence. Santonian-Upper Campanian, B. mucronata Zone; throughout south-east England; also known from Wiltshire and Norfolk; comparatively rare.» CLEEVELY, R. J. & N. J. MORRIS. 2002. Introduction to molluscs and bivalves. In A. B. Smith & D. J. Batten (Eds.): Fossils of the Chalk, 99-160. The Paleontological Association. London. [p. 125]
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Microchlamys sarumensis (Woods); R. J. Cleevely & N. J. Morris, 2002, Introduction to molluscs and bivalves, plate 20, figure 3.
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