"Eburneopecten" frontalis (Dall, 1898)
DALL, W. H. 1898. Contributions to the Tertiary fauna of Florida. Silex Beds of Tampa and the Pliocene Beds of the Caloosahatchie River. Part IV. I. Prionodesmacea: Nucula to Julia. 2. Teleodesmacea: Teredo to Ervilia. Transactions of the Wagner Free Institute of Science of Philadelphia, 3 (4): viii, 571-947 p., pls. 23-35 (pls. 36 and 37 in part 5, 1900) [p. 753]
1895 Pecten rogersi W. B. Clark, 1895
1898 Pecten (Pseudamusium) [sic] frontalis Dall, 1898 [nomen novum pro Pecten rogersi Clark, 1895; partim]
1898 Pecten dalli W. B. Clark, 1898 [nomen novum pro Pecten rogersi Clark, 1895]
1898 Pecten (Pseudamusium) [sic] frontalis Dall, 1898 [nomen novum pro Pecten rogersi Clark, 1895; partim]
1898 Pecten dalli W. B. Clark, 1898 [nomen novum pro Pecten rogersi Clark, 1895]
Pecten rogersi Clark; W. B. Clark, 1896, The Eocene deposits of the Middle Atlantic Slope in Delaware, Maryland and Virginia, pl. 34, figs. 2a-2c.
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«Pecten Rogersi Clark, Bull. U. S. Geol. Surv., No. 141, p. 85, pl. 34, figs. 2 a, b, c, 1896; Johns Hopkins Un. Circ., xv., p. 5, 1895.
Not P. Rogersi Conrad, Journ. Acad. Nat. Sci. Phila. , vii., p. 151, 1834. Eocene of Potomac Creek, Front Royal, Virginia, Clark; Jacksonian of Garland's Creek, Clarke County, near Shubuta, Mississippi, Burns.
The specimen described by Clark is young, only eighteen millimetres in height, but Burns obtained specimens twenty-nine millimetres high by twenty-eight wide in Mississippi. The radial sculpture is obsolete near the centre of the disk and on the beaks, but well marked near the margin. There are about seventy small, low, flattened riblets separated by narrower grooves. The ears are small and the posterior ear smaller and obliquely truncate. The shell is moderately convex and recalls P. choctavensis Aldr., but with much feebler sculpture.» WILLIAM HEALEY DALL, 1898
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«The new tribe Pseudentoliini is defined as a monophyletic group of genera rooted in "Eburneopecten" frontalis (Dall, 1898) (Appendix Note 2) of late Paleocene (Selandian, Thanetian) age in the North Atlantic. As presently understood, evolution from this root led successively through a series of morphologies represented by Pseudentolium corneoides (Harris, 1919), Pseudentolium corneum (J. Sowerby, 1818), and a succession of species in the genus Korobkovia Glibert and van de Poel, 1965. From the beginning of the Ypresian, the tribe was, so far as known, restricted to the seas of Europe and Asia and remained restricted to the Northern Hemisphere until its extinction at the end of the Pliocene.
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).» 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. [p. 12]
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«An explanation of the usage of the name "Eburneopecten" frontalis for a species occurring in the Paleocene and Lower Eocene of Virginia and Maryland is necessary because of errors in the literature. The name Pecten rogersi Clark, 1895, was given by Clark to a species from the Paleocene Aquia Formation of Virginia. Dall (1898, April), recognising that Clark's name is a junior homonym (non Pecten rogersi Conrad, 1834), renamed Clark's species Pecten frontalis and expanded the concept of the species to include younger material from the lower Jackson group of Mississippi (Moodys Branch Formation, early Bartonian in age; Palmer and Brann 1965: 135). Seven months later, Clark (1898, November), apparently unaware of Dall's action, introduced another new name, Pecten dalli, for the same species. Clark and Martin (1901, caption for PI. 44, fig. 7) designated a type specimen for P. rogersi Clark from the Aquia Formation at Potomac Creek, Virginia (now USNM 207171), and recognised that the species extends into the lower Eocene Nanjemoy Formation of Maryland and Virginia. Dall in Schuchert (1905: 487), apparently overlooking the fact that a type had already been designated, incorrectly referred to specimens of Pecten (Pseudamussium) frontalis from the later Eocene at Garlands Creek, Clark County, Mississippi, as "cotypes", believing that these specimens are conspecific with the older specimens from Maryland and Virginia. The Internal Code of Zoological Nomenclature, however, clearly mandates (lCZN 4th Edition, Article 72.7) that a new replacement name has the same type(s) as the original name. Furthermore, specimens in the Smithsonian collections identified by Dall as "Pecten frontalis" from Mississippi are within the range of variation of Eburneopecten scintillatus (Conrad, 1865) from the same locality and are not the same as "Eburneopecten" frontalis from Virginia and Maryland. Palmer and Brann (1965: 135) incorrectly accepted Dall's "cotypes" as valid types and therefore chose to limit application of Dall's name to Upper Eocene specimens from Mississippi. They further suggested that the name Pecten dalli Clark, 1898, in the combination Eburneopecten dalli, should be reinstated, even though it is an objective junior synonym of P. frontalis, and should be used for the Virginia and Maryland species. This is clearly not in accord with the ICZN code.»
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. [p. 43, 44]
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