SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '433ac82af712a83b0534323a65388362c3b5d8cdbc0cd3605bbad51d7a873f99' 
  AND token = 'cdoYW9Y+ykQBnr+SrNz8cRG4vpAerNaZLxvwfhh3458=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

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