SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fff67402014288c9122d9b9ffb5c8239c0ea0d2aa3746f03a6625f2209c6b345' 
  AND token = 'yOgxgGua3TaYIQD/kjbEEJaGSV0rXrBYsZiZzhVsgjs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}