TRANSACTIONS OF THE SAN DIEGO SOCIETY OF NATURAL HISTORY Volume 19 Number 8 pp. 85-106 12 October 1979 Fossil carrion beetles of Pleistocene California asphalt deposits, with a synopsis of Holocene California Silphidae (Insecta: Coleoptera: Silphidae) Scott E. Miller 1 and Stewart B. Peck Abstract. Fossil Silphidae occur in three late Pleistocene asphalt deposits in California: Rancho La Brea in Los Angeles County. McKittrick in Kern County, and Carpinteria in Santa Barbara County. Pierce's 1949 Nicrophorus taxa from Rancho La Brea and McKittrick are all new junior synonyms: Nicrophorus guttula labreae, Nicrophorus mckittricki, Nicrophorus obtusiscutellum, and Nicrophorus investigator latifrons = Nicrophorus marginatus Fabricius; Nicrophorus guttula punctostriatus = Nicrophorus guttula (Motschoulsky); Nicrophorus investigator alpha = Nicrophorus nigrita (Man-nerheim). Lectotypes are designated for N. g. labreae and N. i. alpha. The following resurrected generic combinations are used: Thanatophilus lapponicus (Herbst), Heterosilpha ramosa (Say), Het-erosilpha aenescens (Casey). A neotype is designated for Heterosilpha ramosa. Heterosilpha aenes-cens is a valid species and a lectotype is designated for it. The fauna of each deposit includes: Rancho La Brea: T. lapponicus, H. ramosa (and perhaps H. aenescens), N. marginatus, N. guttula, and N. nigrita; McKittrick: N. guttula and N. marginatus; Carpinteria: N. guttula and N. nigrita. Nicro-phorus marginatus is the best represented species of Nicrophorus in the asphalt, although it is the least common species of the genus in the modern southern California fauna. Possible reasons for this apparent faunal change include real faunal changes and biased preservation. Due to limited knowledge of silphid ecology, detailed paleoecological conclusions cannot be made at the present time. All silphid species presently known from California are reviewed, and a key is given. Aclypea bituberosa (LeConte) (new combination) occurs in the Sierra Nevada Mountains, Thanatophilus sagux (Manner-heim) (new combination) is raised from synonymy, Pelatines latus (Mannerheim) is recorded from northern California, a lectotype is designated for Nicrophorus hecate (Bland), and several other geo-graphic ranges are extended. Introduction Pierce (1949) recognized 6 species and 5 subspecies of Silphidae from the Rancho La Brea and McKittrick asphalt deposits. Two of these species and 4 subspecies were described as new. This study reevaluates Pierce's (1949) taxa and records newly found specimens. In order to place the fossils properly, we review the taxonomy and distri-bution of the Holocene Silphidae of California. Although most of Pierce's basic concepts (Pierce 1961) regarding fossil insects were valid, his publications and taxonomic procedures were replete with errors. Se-rious identification problems result from his erection of taxa based on fragmentary specimens. In addition to poor descriptions, some of his drawings were inaccurate (e.g.. Carpenter 1968, Matthews and Halffter 1968). Our study was hampered by past improper labeling by Pierce and some errors in cataloging many type specimens by Sphon (1973). All the Pleistocene specimens studied represent Holocene species and fall within reasonable ranges of morphological variation. The use of subspecific names is not 1 Research Associate in Invertebrate Paleontology, Natural History Museum of Los Angeles County. Research Associate in Entomology, San Diego Natural History Museum.
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