jaw. The extremely long mandibular symphysis extends to the 23rd or 24th tooth. The snout of adult gharials is 3.5 times longer than the width of the skull's base. Because of this long snout the gharial is especially adapted to catching and eating fish. The nasal bones are rather short and widely spaced from the premaxillae. The jugal bone is raised. It becomes proportionally thicker with age. Two individuals in the weight range of had an average measured bite force of . Male gharials develop a hollow bulbous nasal protuberance at the tip of the snout upon reaching sexual maturity. This protuberance resembles an earthen pot known locally as "ghara". The male's ghara starts growing over the nostrils at an age of 11.5 years and measures about at an age of 15.5 years. It enables the males to emit a hissing sound that can be heard away. The gharial is the only living crocodilian with such visible sexual dimorphism. Mature male gharials have larger skulls than females, exceeding a basal length of and a width of . Female gharials reach sexual maturity at a body length of and grow up to . Males mature at a body length of at least and grow up to a length of . Adult males weigh about on average, with some weighing up to or more. It is among the largest of the living crocodilians, with the heaviest recorded male weighing . A long gharial was killed in the Ghaghara River in Faizabad in August 1920. Male gharials with an alleged length of were sighted around the turn of the 20th century in Indian rivers. Distribution and habitat The gharial once thrived in all the major river systems of the northern Indian subcontinent, from the Indus River in Pakistan, the Ganges in India, the Brahmaputra River in northeastern India and Bangladesh to the Irrawaddy River in Myanmar. In the early 20th century, it was considered common in the Indus River and its Punjabi tributaries. By the early 1980s, it was almost extinct in the Indus. During surveys in 2008 and 2009, no gharial was sighted in the river. It was also present in India's Godavari River but was hunted to extinction between the late 1940s and the 1960s. It was considered extinct in the Koshi River since 1970. In the 1940s, it was numerous in the Barak River in Assam, which held big fish