Cephidae

Common Name

Stem Sawflies

Overview

Cephidae, commonly known as stem sawflies, are a small family of insects within the order Hymenoptera. This group is known for their larval stage, where they bore into plant stems, causing significant agricultural damage.

Taxonomy

  • Order: Hymenoptera
  • Suborder: Symphyta
  • Superfamily: Cephoidea
  • Family: Cephidae

Key Characteristics

  • Appearance: Adults have a wasp-like appearance with slender bodies and long antennae.
  • Size: Generally small to medium-sized, ranging from 5 to 20 mm.
  • Wings: Two pairs of wings, with the hindwings smaller than the forewings.
  • Coloration: Typically black or brown, occasionally with yellow markings.
  • Larvae: Grub-like, lacking legs, and primarily found within stems of host plants.

Life Cycle

  1. Eggs: Laid individually into plant stems using a saw-like ovipositor.
  2. Larvae: Bore into the plant stem, where they feed and develop.
  3. Pupae: Pupation occurs inside the plant stem.
  4. Adults: Emerge from stems, ready to mate and begin the cycle anew.

Behavior and Ecology

  • Feeding: Larvae feed on the pith inside plant stems, often causing the plants to weaken and collapse.
  • Habitat: Prefer temperate regions and are commonly found in fields, meadows, and agricultural lands.
  • Reproduction: Females use their specialized ovipositors to lay eggs within plant stems.

Notable Species

  • Cephus cinctus: Also known as the wheat stem sawfly, a significant pest in cereal crops.
  • Calameuta pallipes: Found across Europe, typically in grassland habitats.

Conservation

  • Status: Most species are not considered at risk; however, their role as agricultural pests makes them targets for pest control measures.
  • Control Mechanisms: Incorporating crop rotation and resistant plant varieties helps manage their populations.

Significance to Humans

  • Agriculture: Some species, like the wheat stem sawfly, are serious pests of cereal crops, causing economic losses.
  • Ecological Impact: They play a role in natural ecosystems by acting as herbivores and prey for other animals.

Fun Facts

  • Sawfly Name: The name "sawfly" comes from the female's saw-like ovipositor used to cut into plant stems.
  • Ancient Lineage: Cephidae have been around since the Mesozoic era.
  • Species Diversity: There are approximately 100 species within the Cephidae family.
  • Plant Specialization: Many species are highly specialized, feeding only on specific host plants.