Chlamys benedicti (Adegoke, 1969)
ADEGOKE, O. S. 1969. Stratigraphy and paleontology of the marine Neogene formations of the Coalinga Region, California. University of California Publications, Bulletin of the Department of Geological Sciences, 80: 1-269, pls. 1-13. [p. 103, pl. 3, figs. 3, 5]
1969 Hinnites benedicti Adegoke, 1969
O. S. Adegoke, 1969, plate 3.
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«Shell medium sized, thin, similar to Hinnites multirugosus crassiplicatus (Gale); outline oblong-oval, much higher than long; ornamented by over 40 low, rounded, subequally prominent ribs; frequently 1 riblet ill each interspace; ribs only slightly spinose, become more prominent, more irregular and more spinose toward ventral margin; anterior ear longer than posterior ear; byssal notch deep.
Dimensions.— Holotype, length 36.0 mm, height 46.7 mm, thickness (one valve) 6.9 mm; paratype no. 36635, length 31.1 mm, height 38.0 mm, thickness (one valve) 6.9 mm; paratype no. 36636, length 36.8 mm, height 47.3 mm, thickness (one valve) 7.9 mm, paratype no. 36637, length 23.2 mm, height 28.6 mm, thickness one squashed valve 4.6 mm.
Holotype.— UCMP no. 36638, locality D-702. Paratypes.— UCMP nos. 36635, 36636, and 36637, locality D-702. Occurrence.— Santa Margarita Formation: D-701, D-702, D-1102. Range.— Late Miocene. Remarks.—This species may be readily distinguished from Hinnites multirugosus crassiplicatus (Gale), which occurs in the same beds, by the more elongate and oval outline and the more numerous but less prominent radial ribs. The "Chlamys stage" lasts longer (28-34 mm) in the new species than it does in crassiplicatus. Additionally, the ribs are remarkably uniform and are only slightly spinose.
The new species is named in honor of my brother Rev. Benedict Adegoke who assisted me in collecting fossils from the Santa Margarita Formation.» OLUWAFAYISOLA SYLVESTER ADEGOKE, 1969
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«Adegoke (1969: 103) described a new species of "Hinnites", Hinnites benedicti Adegoke, 1969, from the Late Miocene Santa Margarita Formation of California. Although this species was found in the same beds as H. multirugosus crassiplicatus (Gale, 1928) [= Crassadoma gigantea], Adegoke regarded it as distinct because of its larger Chlamys stage and more even ribbing. My own examination of Adegoke's types at UCMP confirmed this distinctness but did not confirm that "Hinnites" benedicti has a cementing habit. The maximum size of the Chlamys stage (34 mm) given by Adegoke is exceeded by the height of the holotype (46.8 mm) and two of the paratypes, none of which show any evidence of cementation. The holotype, a right valve, would be expected to show an abrupt sculptural change and xenomorphic growth if cemented. Instead, the degree of shell irregularity is comparable to that of extant Laevichlamys irregularis of the Indo-Pacific, a species with a byssate, nestling living habit. The style of ribbing of H. benedicti and the apparent lack of commarginal lirae suggest that it is not a Crassadoma, but its generic assignment awaits examination of better preserved
material. Most likely it is a Chlamys, s.s. on the basis of its style of ribbing introduction.» WALLER, T. R. 1993. The evolution of Chlamys (Mollusca: Bivalvia: Pectinidae) in the tropical western Atlantic and eastern Pacific. American Malacological Bulletin, 10 (2): 195-249, figs. 1-14. [p. 211]
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