SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '83c44bfe07dace99201a35be16efa3aa969191f48f2e486153e4f9ca6fdefd66' 
  AND token = 'mEwGxKiqa3zRPYSTyob+9XGV4SY9ZkWRxJizX7Bn26Q=' 
  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