SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '14f2d1bad266b9f1853f4f3d352d88cacc8f07af63fe9547bd82f9063c69280c' 
  AND token = 'ipuN7Uzw7RsWCb+wwr1e6O6Jqgvzg73KugTfiW1Zm9E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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