SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '99958f1e9515efd6dec7fe95c008671a25f4e141044cc3e7289e5e9255fa08cf' 
  AND token = '9D6Jrl934hF9ck6SqV6/iqVIt3KwyEqRZGP3Zi8mhAw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

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