SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '26bfb5016521eb01421e01daf391f7cc9614fc40dcd81fdbf0aa5dedfd308ba4' 
  AND token = 'YVTGGqdfzgFUdQ+WWCC7K/foLC/jljTHZX2H4CrAF5E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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