SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a62c9d789a6fd896511111fe9d8fbf7eaf277b09c1988173aaedac59962f3ad' 
  AND token = 'PROrr/5lZxmwHZ6P5cKh7I+IuyZHPkGIpni3TVRXoSw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

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