by Jack D. Mount¹
In 1953 Bonnie C. Templeton of the Los Angeles County Museum of Natural History named and described a new species of fossil pine cone, Pinus paucisquamosa Templeton, based on a specimen that was collected along the beach between Cabrillo Beach and Point Fermin in San Pedro, California. During the summer of 1963 I visited the area of the type locality in an attempt to find additional pine cones. I was not successful, but I did collect a large silicified insect. Last month I showed it to Ken Frey who identified it as the nymph stage of a dragonfly. The specimen is now in the invertebrate paleontology collection of the Los Angeles County Museum of Natural History.
The slab of rock containing the insect was found as float material on the rocky beach below a high sea cliff about midway between Cabrillo Beach Museum and Lookout Point on Point Fermin.
The dragonfly is in cherty shale which, although found loose, is similar to rocks found in place in the cliffs. The geologic map in Woodring, Bramlette and Kew (1946) assignes the rocks of this area to the Altamira Shale Member of the Monterey Shale. On the basis of foraminifera, shale from this area is assigned to the Luisian Stage, Middle Miocene, by Kleinpell (in Woodring, Bramlette and Kew, 1946, p.24).
Fig. 1
Dragonfly Nymph from San Pedro, Calif. Miocene Fig. 1 |
Palmer, A. R., et al., 1957, Miocene arthropods from the Mojave Desert, California: U. S. Geol. Survey Prof. Paper 294-G, p. 237-280, 5 plates.
Templeton, B. C., 1953, A new record of pine cone for the Miocene Epoch: Bull. So. Calif. Acad. Sci., vol. 52, p. 64-66.
Woodring, W. P., Bramlette, M. N., and Kew, W. S. W., 1946, Geology and paleontology of Palos Verdes Hills, California: U. S. Geol. Survey Prof. Paper 207, 145 P.
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¹Southern California Paleontological Society. 1516 So. 5th St., Apt.H, Alhambra, CA 91803.
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