Cephidae

Taxonomy

Superfamily: Cephoidea
Family: Cephidae
Family common name: stem sawflies
Subfamilies: Athetocephinae, Australcephinae, Cephinae

Background

The family Cephidae are known as the stem sawflies because of their larval habit of boring into stems of various plants (Smith and Middlekauff 1987). They are easily recognized by slender, elongated bodies and missing cenchri (Middlekauff 1969). This family includes some economically significant pests of wheat crops (Smith and Middlekauff 1987).

Diversity

Cephidae includes 24 genera and 165 species worldwide. About 6 genera and 16 species are Nearctic in distribution (Taeger et al. 2018).

North American genera

Caenocephus
Calameuta
Cephus
Janus
Phylloecus
Trachelus

Diagnostic characteristics

Host associations

In North America, Cephidae feeds on species in the families Poaceae, Rosaceae, and Adoxaceae (Goulet 1992).

May be confused with

Cephidae can be distinguished from other families by the lack of cenchri, lack of cornus, and long cylindrical body (Goulet 1992).

Life history

Cephidae sawflies bore into stems of the host plant, creating galleries in which they usually pupate. The sawflies of the subfamily Cephinae are often pests because they girdle stems of economically important grass crops, such as wheat and barley (Smith and Middlekauff 1987).

Distribution

World: This family is Holarctic, known from North America, Europe, and Asia (Taeger et al. 2010). Two species occur in Madagascar (Middlekauff 1969).

North America: Cephidae is most common in the northeastern United States and the Great Lakes region, though species occur throughout the United States and most of Canada (Middlekauff 1969, Goulet 1992).

Calameuta clavata female lateral habitus; photo by J. Orr, WSDA

Calameuta clavata female lateral habitus; photo by J. Orr, WSDA

Janus rufiventris male lateral habitus; photo by J. Orr, WSDA

Janus rufiventris male lateral habitus; photo by J. Orr, WSDA

Trachelus tabidus male lateral habitus; photo by J. Orr, WSDA

Trachelus tabidus male lateral habitus; photo by J. Orr, WSDA

Cephus cinctus male lateral habitus; photo by J. Orr, WSDA

Cephus cinctus male lateral habitus; photo by J. Orr, WSDA