SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a9381a97a8b2321f662023274ad367b9df5fcee6e672fbc3524dd9f08f3d9561' 
  AND token = 'cEgjJQWNtQj6pdJrn0QFOnL7Pb8xWHTFW/MEHqadnxA=' 
  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