Panorpidae (family) are called scorpionflies because of the abruptly enlarged tip of the abdomen, like the scorpion (Resh and Cardel 2003).  This is the only resemblance, however, meaning the scorpionfly does not bite humans.  Members are 15-20 mm long and usually have slender bodies with four long, narrow wings (Swan and Papp 1972).  These wings are marked with dark spots, bands, or darkening along the crossveins (California Academy of Sciences 2009).  They have long faces with a mouth projecting downward at right angles forming a beak-like rostrum (Resh and Cardel 2003). Also, Panorpa sigmoides have long, thread-like antennae, three simple eyes, well developed compound eyes, and long, slender legs adapted for walking (Resh and Cardel 2003).