SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1807273d7ffec404e9456e0e2f8f2253e679f0efc92aea665f85f35b1468021c' 
  AND token = 'pFnwjHFRSx0eyvlMFIEti3le4i7uOdBkxD++msPpxls=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

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