SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3a1ac6f1258255fd64d03c6e5c176ff6b652c86a4e5cb40ed2c2a0496fabf9aa' 
  AND token = '38PYT6vd7c5trDYiIC0yS7ozHp1aWh1IqIodoPmstqU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

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