Banded archerfish colourations, such as yellow, have been observed. Four to six broad black bars may be present on the dorsal side. The first bar is found anterior to the operculum, the bony plate covering the gills, and the second is found behind the operculum. The third bar is found below the origin of the dorsal fin, the fourth bar below the soft dorsal, and the fifth (if any) on the area between the anal fin and caudal fin (caudal peduncle). These bars become shorter as the fish ages. The lateral line curves upwards at the area between the fourth and ninth
Yunnanilus macrogaster a short lateral line which has 6–10 pores and a line of pores on the head. The caudal peduncle is around 1.4 times as long as it is deep and its eyes have a diameter of slightly less than one fifth of the head length. It grows to a standard length of 63.2 mm. The body is yellowish with an irregular pattern of brown spots on its back and flanks with the dorsal surface of the head being darker and there is a dark patch on the operculum to the rear of the eye. The fins are hyaline and the