Megaloptera: Sialidae (Alderfly)
- Elongated, flattened from top to bottom; 3 pairs of jointed legs, each with 2 claws.
- Head with well-developed chewing mouth parts.
- Wing pads absent.
- Abdominal segments have 1 pair of lateral filaments.
- Last abdominal segment ends in a single, unbranched filament.
Length: 10 mm to 25 mm
Peter Chen.