SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8942b928c0fbff38b7f1c28f5d9ca6bc3105384808bc7ad7ea3207e67d1d1c50' 
  AND token = 'UDlWHrJplORU0nLkKhKe/CEbgtveGWiqCVFXX8UakwY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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