It really does not make much sense to call those designs icons or iconic. If you are saying they are representative symbols of dive watches, chronographs or moon phase watches there are plenty of others that meet that criteria. If you are using iconic to mean the first or most popular then why not say it. Those are popular designs that may have been originated by one company but that's about it.
My query is as I put it, a watch with the moonphase function that has been around for a while and has remained relatively unchanged in its design throughout the years, that it has been around for a while would suggest that it is popular or maybe even the most popular, but not necessarily the first. I suppose the inspiration behind my query are those lists of iconic watches that come out from time to time that often lists out dive watches, chronographs, dress watches etc but never a watch with a moonphase function.
So if you asked the WUS community what they thought was the iconic chronograph, I would not be surprised if many said the Omega Speedmaster, or for a dive watch - the Rolex Submariner. Therefore, I wonder if there is such a thing as an iconic watch with a moonphase complication. Based on the responses so far, there doesn't appear to be a clear consensus on the matter, but there are 2 votes for the IWC Perpetual Calendar above.