This fish is truly one of the holy grails of the scorpionfish collector. Their coloration pattern and often wild-looking dermal flaps and appendages truly make this fish an eye-popper. This fish’s appearance is dependent upon where it was collected. Those that are found in areas of high coralline or other algal growth are often adorned with many more dermal flaps than those specimens collected on open substrates. Two main characteristics identify this species, one of which is an incised dorsal fin, and the other being the presence of sub-ocular appendages just below and between the eyes. Coloration and markings can be variable, but the weedy scorpionfish is typically marked with complex patterns of ocelli and have a lacy appearance to their pectoral fins. The body is extremely laterally compressed, and this fish will often sway in the current mimicking a clump of algae.
R. frondosa gets along well with most fish, and make excellent tankmates for larger fish in most settings. It should be given plenty of open space, as it rarely swims, preferring to hop and crutch along on its lacy pectorals. It is a fairly sedentary fish, but when the fish is hungry, it tends to be a bit more active, and will indeed pray to the food god.