The majority of adult Hydrophiinae species grow to between 120 and 150 cm (3.9 and 4.9 ft) in length,[5] with the largest, Hydrophis spiralis, reaching a maximum of 3 m (9.8 ft).[6] Their eyes are relatively small with a round pupil[7] and most have nostrils that are located dorsally.[8] The skulls do not differ significantly from terrestrial elapids, although the dentition is relatively primitive with short fangs and (with the exception of Emydocephalus) as many as 18 smaller teeth behind them on the maxilla