SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8d3bcf4b59e35c19c2d7c98d00f4f2ba1c9af058dcfce9f2a364fd458f7520f6' 
  AND token = 'wdbyKA1+PlPew18PR+76N93Z7oEe398AD3KN4XpDJb8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables