Cybocephalidae and Nitidulidae (picnic or sap beetles) - Introduction

by Joe MacGown

5 August 2010


Since the early 1990's, survey work has been conducted in Mississippi to identify Nitidulidae species and distributions throughout the state. The survey has been lead by Clarence Collison, although members of the Mississippi Entomological Museum (MEM) have greatly contributed to the effort by collecting, pinning, and labeling specimens. More recently, Paul Lago (University of Mississippi) and Andy Cline (California Dept. of Food and Agriculture) have been involved with the project. Ultimately, a publication documenting the Nitidulidae of Mississippi will be produced. Presently, this web site only lists identified specimens housed in the MEM and does not include any distributional data, which will be included in the final publication.

Currently, there are five recognized subfamilies of Nitidulidae in the U.S.: Cilaeinae, Carpophilinae, Nitidulinae, Meligethinae, and Cryptarchinae. Until recently, Cybocephalinae was also considered to be a subfamily in Nitidulidae, but it was elevated to family status by Smith and Cave (2006), although some researchers may still consider it to be a subfamily. Approximately 165 named species in 30 genera are known to occur in the United States.

Nitidulid beetles are quite variable and may be oval to elongate, convex to extremely flattened. They range in length from 1.5 to 12 mm. Color varies from pale to black, often with red or yellow markings. The head is not concealed from above. Punctures are usually present on the dorsum. Elytra are often shortened and may expose the terminal segments of the abdomen. Pronotal margins are often explanate (expanded and thin). The antenna is 11-segmented and has a three-segmented club. The tarsal formula is 5-5-5 or 4-4-4. (Habeck 2002).

Most nitidulids feed on decaying organic matter (saprophytic) or fungi (mycetophagous) and may live in flowers, decaying fruits, fungi, fermenting plant juices, carrion, bee nest, ant colonies, and other microhabitats. One species, Aethina tumida, lives in honey bee colonies, and is a serious pest in the U.S.

Literature Cited
Habeck D.H. 2002. Nitidulidae, in: American Beetles, Vol. 2, Arnett R.H., Thomas M.C., Skelley P.E., Frank J.H. (Eds.), CRC Press, Boca Raton, pp. 311–315.

Smith, T. R. and R. D. Cave. 2006. The Cybocephalidae (Coleoptera) of America North of Mexico. Annals of the Entomological Society of America 99: 776-792.