BEIJING - A bug over half a metre long discovered in southern China has been declared the world’s longest insect, state media said Thursday. A stick insect measuring 62.4 centimetres found two years ago in the southern province of Guangxi has broken the record for length amongst the world’s 807,625 known insects, the official Xinhua agency said, citing the Insect Museum of West China. The previous record-holder was a Malaysian 56.7-centimetre-long stick insect discovered in 2008 and now on display in London’s Natural History Museum. Tipped off by locals about a huge beast half a metre long but as thick as a human index finger, scientist Zhao Li had been on the hunt for the bug for six years before he finally glimpsed and captured one.  The bug has been dubbed Phryganistria chinensis Zhao in his honour, and a paper about it will soon be published.