SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e48291650d1904a03399ca76ac376818aa14e7cfeeeca9914e2481eb0a77d44' 
  AND token = '/bthiJzQbM3UQlaCfIM/fuhYw/W/Jfb44+ilbFv9DoA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

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