SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ae6f68bfa4ef3249bb5a9b466e7d50e0c8b9c53dfe16db8fbb6b45f12202bd6' 
  AND token = 'CeVZvDzFjJnDl5/OIqnPp3l2Pjrd9w9R8Kk9ol5mSL0=' 
  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