Juvenile batfishes in the genus Platax (Ephippidae) are known to have striking coloration that is considered to be protective (Randall 2005). Juvenile Indo-Pacific P. teira and P. orbicularis have broad dark and silver vertical bands. This coloration contrasts sharply with blue waters and resembles, at least to the human eye, floating debris or seaweed, cages, mooring lines, shipwrecks, and aspects of other habitats where they typically occur. We found Platax teira (longfin batfish) consistently occurring in a shallow bed of the seagrass Enhalus acoroides on Barrang Lompo, one of the many Spermonde islands off South Sulawesi, Indonesia. Their color banding provides virtually no contrast against the seagrass. Seagrass might provide very good habitat for juvenile batfish, although we have found no published reports of juvenile batfishes in seagrass beds. Juvenile batfishes are both herbivorous and carnivorous (Barros et al. 2013); in seagrass, they would have abundant plant food and their coloration could conceal them from either their prey or predators. Herbivory by juvenile batfish hidden in seagrass might help reduce deleterious epiphytes that bloom on seagrasses in the face of coastal eutrophication (Fig. 1).

Fig. 1
figure 1

Juvenile batfish (Platax teira) in Enhalus acoroides, Barrang Lompo, Spermonde Islands, South Sulawesi, Indonesia

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