SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c59a20a67d1bc77e14225659db0aef3724ed03acdf13ca553bd1470e4b419c84' 
  AND token = 'QWciB9u5zIuQToO+mDWVqC2pqGHDg0iiTjiFR4lxAhE=' 
  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