SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '883c3f139b2954db520544c15174af33b2bedeb0946d15e7f5d9100ca804233b' 
  AND token = 'r35NDd/fOKIkcnJBmhq8hYigEzC/9jx0ULT0iluFLp8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

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