Chlamys hertleini (Loel & Corey, 1932)
LOEL, W.
& W. H. COREY. 1932.
The Vaqueros formation, lower Miocene of California I. Paleontology. University
of California Publications, Bulletin of the Department of Geological Sciences,
22 (3): 31-410, pls. 4-65. [p. 195, pl. 20, figs. 4, 6-8]
1932 Pecten (Chlamys) hertleini Loel & Corey, 1932
W. Loel & W. H. Corey, 1932, plate 20.
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«Holotype and Cotype 31725, 31726, Univ. Calif. Coll. Invert. Pal., loc. 5-15 (collected by R. N. Nelson).
Plesiotypes 31727, 31728, loc. A316. Shell medium thin, about as long as high; valves subequal, slightly convex and subequilateral except for ears; anterior sides concave, posterior straight, base regularly rounded; umbonal angle 80 degrees. Right valve ornamented by many fine, evenly spaced, minutely noded ribs which number about 60 at the periphery. These ribs are progressively added to outwardly by the strengthening of interculary ribs, all being of equal strength at the margin; fine incremental lines form the nodes on the ribs and also in the interspaces which are about as wide as ribs. Anterior ear long, ornamented by seven fine riblets, the concentric incremental lines strong forming nodes on ribs and strong lines between ear and margin; byssal notch deep. Left valve similar in all characters save for shallower byssal notch. Height, 46 mm.; length, 40 mm.; diameter, 10 mm. (both valves).
Holotype 31725, Cotype 31726, from Univ. Calif. loc. 5-15 (collected by R. N. Nelson). Vaqueros of Santa Ynez River Canyon, Santa Barbara County; R. N. Nelson, collector. Found in association with P. magnolia and Ostrea eldridgei. Plesiotypes collected by W. H. Corey. This distinctive Pecten (Chlamys) is different from all others in the Tertiary of the West Coast. On another specimen from the same locality, the posterior ears are seen to be ornamented in the same manner as the posterior ears and squarely truncate. Specimens from the Vaqueros of the western Santa Ynez Mountains (Univ. Calif. loc. A316), are all small with rib number at the periphery generally less than the type or larger form. The rib number is proportional to the size of the individual. Named in honor of Dr. L. G. Hertlein through whose generosity much valuable information was made available to the writers. Pecten (Chlamys) hertleini, n. sp. differs from P. sespeensis Arnold in its distinctively uniform and greater number of ribs—adult specimens of the latter species never have more than about 30 ribs and those are unevenly developed. A Pecten (Chlamys) form which occurs in the Kern River Temblor is somewhat similar in appearance to this new species but has considerably fewer and paired ribs. The Temblor form may possibly occupy an intermediate position between P. (C.) Hertleini and P. (C.) sespeensis Arnold (1906). Since this description was written, the species has been found represented by large numbers of specimens in collections from the Channel Islands, particularly Santa Rosa Island, where it is evidently abundant. Geologic range.— Vaqueros horizon, Lower Miocene only? Distribution.— Western Santa Ynez Mountains, south of Buelton, and Santa Ynez River Canyon, Santa Barbara County, seen in well cores from the south end San Joaquin Valley, Kern County. Horizon not known. Abundant on the Channel Islands (Santa Rosa and San Miguel islands).» WAYNE LOEL & WILLIAM HENRY COREY, 1932
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«Comments.— The holotype is a poorly preserved, double-valved specimen with a small umbonal angle. The right-valve auricles are broken, but the byssal notch is wide. Both valves are similarly sculptured.
Geographic range.— Middle and southern California. Geologic range.— Oligocene to Miocene. Occurrence in California.— Oligocene: Quail Canyon Sandstone Member, Vaqueros Formation (Loel and Corey, 1932; Vedder, 1973); Oligocene and Miocene: Rincon Shale (Avila and Weaver, 1969), Soda Lake Shale Member, Vaqueros (Vedder, 1973) and Temblor (Page and others, 1951) Formations; Miocene: Jewett Sand (Addicott, 1965 and 1967b), Monterey Formation (Avila and Weaver, 1969), Painted Rock Sandstone Member, Vaqueros Formation (Vedder, 1973), and Skooner Gulch Formation (Addicott, 1967b).» MOORE, E. J. 1984. Tertiary Marine Pelecypods of California: Propeamussidae and Pectinidae. United States Geological Survey Professional Paper, 1228-B: iv + B1-B112, figs. 1-2, pls. 1-42. [B21]
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Chlamys hertleini (Loel and Corey; E. J. Moore, 1984, Tertiary Marine Pelecypods of California: Propeamussidae and Pectinidae, plate 4, figures 7, 8.
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