SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd3b6261ba23248e6ee7ab2d113c85df846371eeb451988d8dea6957ec6ee435' 
  AND token = 'wqyfcGJeGJNNDv3ugu3y9LfRM7Jv46XxaIfhd6D3pdI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

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