SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1eaf9f03a81d543549014ae383bb80f83aab25c35f717dbcdb76fe1c400370e8' 
  AND token = 'QnduOBOMFf8RaYRaNihT/2ynbbhP4IIQtdZAx1plhq0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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