I saw this fish at Tajiguas on 16 July, on the sand at about 2 pm. It was about 3 inches long, and flitting across the sand. It was quite shy, and didn't want me to photograph it. It swam with its pectoral fins, also moving its tail and dorsal fins. To me, it looks most like the Souther Poacher in Coastal Fish ID. However, it was out in daylight, wasn't well camoflaged, didn't have bars, and was definitely aware and afraid of this diver.