SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97ea9f73ea8c5fc98a396ed28b053959717b03f7a53e2603f0f3adaa70c5fa3d' 
  AND token = 'bnIft8amTvuTp+v7PbgJsM43SjGu4pBgyw/24YNYr2Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

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