SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6762c01c19ff8bfe8b9fb4484000f56aeb6a8caf4c26e0ec16c064ab801ff5c6' 
  AND token = 'xU1GFHnqry+q4Mtd9uyc2lIYLt7k9p+IVdqZ/2eJxL0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

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