SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b9b7c3867f245a5bd4eed5fb8f0dd1c048f98c0e5610277ac5f4f29862f98cbb' 
  AND token = 'LfsQ3U39aPJB18u8eZOlrh6oTNInFz8iDGkivWwjH3M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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