SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c643c0a17f7ea30ae29042bfb6c154a5d815f650a4ed0e5437685b5e56fcc871' 
  AND token = 'KGtq5XkB8PnQNzhRq3V5Y6cqfZYyNln62tBoMxEKjdg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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