Dhondtichlamys arlesiensis (H. Woods, 1902)
WOODS, H. 1902-1903. A monograph of the Cretaceus
Lamellibranchia of England. Vol. I. Part IV Pectinidae, 145-196 p. (1902);
Part V Pectinidae (continued), 197-232 p. (1903). The Paleontographical Society
(First reprinting, 1975: Vol. 56 nº 264 and Vol. 57 nº 267). [p. 194, pl. 37, figs. 9-11]
1870 Pecten vraconensis Pictet & Campiche, 1870 [nomen oblitum]
1902 Pecten (Aequipecten) arlesiensis H. Woods, 1902
1902 Pecten (Aequipecten) arlesiensis H. Woods, 1902
H. Woods, 1902-1903, plate 37.
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«Description.— Shell small, nearly circular, pointed dorsally, height and length nearly equal; nearly equilateral; convexity moderate. Apical angle about 103°. Ears very unequal.
Right valve with fifteen or sixteen strong, rounded, radial ribs, which are undivided, and of nearly equal size, but somewhat smaller anteriorly and posteriorly. Ribs separated by strong, rounded grooves, a little narrower than the ribs. Fine, regularly-placed, concentric ridges cross both ribs and grooves, and are best marked near the umbo; on the ribs they develop into rather prominent, projecting scales. Near the posterior border of the valve the grooves are marked obliquely by closely set striae. Anterior ear very long, with a deep sinus, and two or three radial ribs bearing scales or tubercles. Posterior ear much shorter, the outer angle approximately rectangular. Left valve with similar ornamentation, but the ribs rather narrower and the scales somewhat more widely separated.
(1, 3, 4) Totternhoe Stoue, Arlesey.
(2) Chalk Marl, Folkestone. Affinities.— This species resembles the form referred by Geinitz (from the Turonian), and by Fritsch, to P. pulchellus, Nilsson (see p. 196), but it differs in having fewer and more widely separated ribs. These characters, as well as the scales on the ribs, also separate P. arlesiensis from P. campaniensis, d'Orbigny.
Types.— From the Chalk Marl of Folkestone. Distribution.— Chalk Marl of Folkestone, and from a deep boring in the axis of the Winchester anticline. Totternhoe Stone (H. subglobosus zone) of Arlesey.» HENRY WOODS, 1902
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«Description. Very small species with moderately convex valves of an orbicular acline shape. Left valve ornamented by elevated straight, narrow ribs. Right valve covered with straight, rounded ribs, which are mostly wider than the intercostal intervals. Thin concentric ornament produces scales where it crosses the ribs.
Remarks. Distinguished by its undivided ribs, 14-18 in number. Occurrence. Cenomanian; south-east England; relatively 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 arlesiensis (Woods); R. J. Cleevely & N. J. Morris, 2002, Introduction to molluscs and bivalves, plate 20, figure 4.
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