SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '4fe9598fd389b2f38a25f95bad4338fa327802c11806a4c720d7058f691c5c84' 
  AND token = 'tUT5YrnumU1m0Sptqj+Jyjm1EYZAv5xOaz3VXsSHKG0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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