Key to genera of South America Sericini

1. Anterior margin of labium weakly concave .............................................................................. 2

1’. Anterior margin of labium deeply concave................................................................ Sayloria

2. Abdomen without lateral carina. Total length of body less than 6 mm. Antennal club always short (never exceeding the length of the remaining antennomeres combined). Elytra often bicoloured...................................................................................................... 3

2’. Abdomen with distinct lateral carina. Total length of body greater than 7 mm. Elytra usually unicoloured, yellowish, blackish or brown. Antennal club longer or short. 4

3. Suture between propygidium and apical ventrite present. Protibia always with three teeth................................................................. ................................................................. Raysymmela

3’. Suture between propygidium and apical ventrite absent. Protibia with one or two teeth.......................................................................................................................................... Symmela

4. Antenna with eight antennomeres; antennal club of males with four antennomeres; fifth antennomere often transversely expanded basally. Phallobase short and stout (lateral view)........................................................................................................................ Miotemna

4’. Antenna with eight or nine antennomeres; antennal club of males with three antennomeres; fifth antennomere never transversely expanded at base. Phallobase longer, at least three times as long as wide (lateral view)............ Astaena