SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '92240cb6bb9cf49ffeb7b5d2604465f89afe7fad89608a1453478fc81e82432f' 
  AND token = 'DXBY65Pc4PuqqYmxcwK9raEGa3qWBkth9vzS3jxMZiA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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