Cephoidea

Definition

A small superfamily of sawflies (suborder Symphyta, order Hymenoptera) containing roughly 100 extant species in 10 genera, placed in the family Cephidae, plus 17 extinct genera in the family Sepulcidae. Members are diurnal, exceptionally slender among symphytans, lack cenchri (the coupling structures between fore- and hindwings characteristic of other Symphyta), and are hypothesized by some to be the sister group to Apocrita (the wasps, bees, and ants). Larvae are stem borers in grasses and other herbaceous plants, with a few species reaching pest status in cereal crops.

Etymology

From Greek kephē 'head' + -oidea (resembling), referring to the family Cephidae and ultimately to head morphology.

Example

The wheat stem sawfly, Cephus cinctus (family Cephidae, superfamily Cephoidea), is a significant pest of wheat in North America, with larvae tunneling through stems and causing lodging.

Synonyms

• Stem sawflies

Related Terms

• Symphyta
• Apocrita
• Cephidae
• cenchri
• sawfly
• stem borer
• Orussidae

Usage Notes

Cephoidea is one of the smallest superfamilies within Symphyta and is distinguished from other sawfly groups by the absence of cenchri. The phylogenetic position of Cephoidea remains debated: while sometimes proposed as sister to Apocrita, the family Orussidae is more commonly accepted in that role. The superfamily has a sparse fossil record extending to the Late Triassic (Norian, ~212 Ma). Most extant diversity occurs in the Northern Hemisphere, particularly Eurasia.