Pseudentolium corneoides (Harris, 1919)
HARRIS, G. D. 1919. Pelecypoda of the St. Maurice and Claiborne Stages. Bulletins of American Paleontology, 6 (31): 5-268, pls. 1-59. [p. 28, pl. 15, figs. 15, 16]
1919 Pecten scintillatus var. corneoides Harris, 1919 [partim]
G. D. Harris, 1919, plate 15.
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«Pseudamusium claibornense Har., partim, Bull. Am. Pal., vol. 2, p. 235, pl. 13, fig. 1.
P. calvatus Dall (non Mort.), partim, Trans. Wag., Ill, 98, p. 752. P. scintillatus Dall, partim, id., p. 752. Specific characterization. — Form and size as indicated by the figures (see also fig. in Bull. Am. Pal. referred to in the synonymy); substance of the shell thicker when adult than in scintiilatus of the Jacksonian; appearance like that of corneus of England, though smaller; surface practically without markings save the fine concentric lines of growth and a few radiating rays on the anterior ear, such rays when adult, separated by a rather broad, smooth space from the anterior margin of the shell as indicated in fig. 16; posterior ear in adult shell with exterior angle apapproximating 90° and not so obtuse as in scintiilatus (fig. 14) nor so acute as in calvatus; young shells in Mississippi, St. Maurice stage, approaching close in outline to scintiilatus, but here as elsewhere so far as observed no Camptonectes marking (so finely shown in scintillatus) have been observed; left valve very flat in umbonal region, becoming deeper centrally and basally, with a faint, medial fold rapidly expanding basally.
Type specimen.—The Hatchetigbee specimen figured in Bull. Am. Pal, as cited above. Horizon.—Sabine and St. Maurice. Specimensfigured.— Deposited in C. U. Mus., St. Maurice. Localities.— Three miles E. of Alto, Cherokee Co., near Crockett, Houston Co., Tex. St. Maurice, Winnfield Marble Quarry and Hammett's Branch, La. Hickory and Wantubbee, Miss. Hatchetigbee, and base of bluff at Claiborne, Ala. Specimens of this form from Enterprise Miss., in the U.S. Nat. Museum, No. 137,665, are labelled P. scintillatus.» GILBERT DENNISON HARRIS, 1919
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«At the base of this clade (A2 in Fig. 1.2), "Eburneopecten" frontalis, from the Upper Paleocene and Lower Eocene of Maryland, has the basic shape of Paleocene Dhondtichlamys and shares similar auricular costae and byssal fasciole. However, in contrast to the coarse plicae and strong antimarginal microsculpture of Dhondtichlamys, "E." frontalis has nearly obsolete but ontogenetically continuous low, broad radial ribs and very fine antimarginal microsculpture. "E." frontalis is closely followed stratigraphically by Pseudentolium corneoides in the early Ypresian of the North American Gulf Coast (A3, Fig. 1.2). This species, previously assigned to Eburneopecten (Palmer and Brann 1965: 134), is placed here in Pseudentolium because it displays distinctive features that characterise the taxa above Node A3. These features are associated with an evolutionary trend toward an amussioid adaptive form: a broad, low radial ridge on the inner surface of the disk inside each disk flank, disk gapes, auricular buttresses ending in low tubercles, a shallowing of the byssal notch, a reduction on the ontogenetic persistence of an active ctenolium, the formation of margins of the left auricles and of the right posterior auricle that form obtuse angles with the hinge line, and the complete loss of auricular costae.»
WALLER, T. R. 2006. New Phylogenies of the Pectinidae (Mollusca: Bivalvia): reconciling Morphological and Molecular Approaches. In S.E. Shumway & G.J. Parsons (Ed.) 2006: Scallops: Biology, Ecology and Aquaculture, 1-44, figs. 1.1-1.4. [p. 12]
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Figure 1.2. A phylogeny of the six tribes of the subfamily Palliolinae.
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«Eburneopecten corneoides (Harris) Amusiidae
Not Pecten claibornensis Harris, 1894b, p. 145 Pseudamussium claibornense Harris, 1897b, p. 43, pl. 7, fig. 1 not of Conrad, 1866a, p. 23 (as Camptonectes); Brann and Kent, 1960, p. 741 Pecten scintillatus var. corneoides Harris, 1919, p. 28, in part, not pl. 15, figs. 15, 16; Brann and Kent, 1960, p. 669 not p. 670 = Eburneopecten sp. Pecten (Pseudamusium) scintillatus Conrad, Dall, 1898b, p. 753 in part Amusium (Pseudamussium) corneoides (Harris), Tucker-Rowland, 1938, p. 65 in part, not pl. 5, fig. 13 not cotype; not pl. 6, fig. 11 not cotype Eburneopecten corneoides (Harris), Stenzel, Krause, and Twining, 1957, p. 85 Range.— Lower Eocene. Bashi mem. (type), Hatchetigbee fm., upper Wilcox [Sabine] gr.
Locality.— ALA.: NE. Washington Co., Hatchetigbee Bluff, Tombigbee R. (type) Type.— Holotype, No. 185 PRI» PALMER, V. W. K. & D. C. BRANN. 1965. Catalogue of the Paleocene and Eocene mollusca of the southern and eastern United States. Part I. Pelecypoda, Amphineura, Pteropoda, Scaphopoda, and Cephalopoda. Bulletins of American Paleontology, 48 (218): 1-466, pls. 1-3. [p. 134]
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