SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '68e6cd84eefa7f8b2561da1194a661fd3a2965bdd17993ec399e6cb82b561162' 
  AND token = 'odrWg6Uf/38crQucZcx+COoehk0wr7lWp6ZkgA3tR5Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

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