Couplet 82

82a:  Pronotum extended forward, covering head in dorsal view; 1 or more ventrites often with luminous organs (most obvious in males); antennal insertions separated by distance < diameter of antennal fossa

Lampyridae   p. 423

82b:  Head exposed in dorsal view when extended; if covered by pronotum, then antenna separated by nearly 2X diameter of antennal fossa; abdomen lacking in luminous organs