Pretty snake. But I agree with Serp, it just looks like a few conjoined saddles. Not all that uncommon or indicative of Motley.
As for Miami? I wouldn't say so. Then again all people's opinion on what makes a Miami a Miami differ greatly. To me its too orangey to be considered a Miami (should be grey background and red/crimson saddles). Check out
www.lowbellyreptiles.com for some great shots of Miami's.
But...you really might want to re-think the sand substrate. Cornsnakes are not desert species, they come from a temperate area of the Southeastern United States.
Sand is not advised for a variety of reasons:
1. It can get under scales and cause irritation and sores. (Imagine coming home from the beach and STILL picking sand out of places you can't name in public.)
2. It has a very drying effect on the microclimate within the viv, and it will suck up any moisture in the area. Which could cause some pretty nasty sheds.
3. If you feed in the tank and it gets ingested, it can/will cause an impaction. And by the time you figure out what was wrong, it'll be too late to save the snake. Calci-sand takes quite a bit of liquid to dissolve completely, and that amount of liquid is not always present in the digestive tract of a reptile, so its not going to be completely dissolved.
4. Its unsanitary. Bits and pieces with fecal matter will get missed when spot cleaning.
5. It's expensive. To do a thorough cage cleaning once a month or so is going to be a terrible waste.
There are a few viable alternatives that are indeed more comfortable for the snake and your wallet.
I highly recommend shredded aspen bedding. Its inexpensive, attractive, absorbs odor/moisture well, and is toxin free. Steer clear of pine/cedar, if you haven't read about that yet.
Or there's always Carefresh, hemp bedding, or the ugly stand-bys newspaper/papertowel.
Hope that helps a little. =)