SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5576d75699cc2b8b880f80395675b2a765a7207e86d23087cf8ce7f56605884a' 
  AND token = '/QFjgHQwwKU7+68qIvTpWKhj3Wskjs9OAzBSR74pxJw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00061

JSON explain

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