SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1406fe9a05344a279923f4e265deb0179599540b0d637d3b545ed1cc9fa261a6' 
  AND token = 'Rfx/2cWY1tzuozFhtqlepbam7+zqV1L7ZV5+huVg7+I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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