 The spines observed by Russel & Emery (1960) had minimum lengths of 5 mm and maximum lengths of 29 mm and were quite heterogeneous in their appearance on a microscopic level.The dorsal spines are all bent very slightly towards the tail of the fish.The mechanism of envenomation is quite similar to that of the opercular spines.⁠

The glands producing "T. draco"’s venom are located in the derma of the fish.