The Phasmid Study Group is a group for professional and amateur entomologists who are interested in the order Phasmatodea, i.e. stick and leaf insects, known as "phasmids", as well as other interested persons. Over 40 species of Phasmid have been named after members of the group. The group includes world experts in the study of phasmids worldwide.
The group was formed in 1980 and has since developed a worldwide membership. It has meetings twice a year at The Natural History Museum, London. It also distributes phasmids, free of charge, to its members.
The group has two publications. Phasmid Studies is issued occasionally and contains scientific papers and longer articles. The Phasmid Study Group's Newsletter is posted to each member twice a year, it contains shorter articles and announcements, and is printed in full colour with lots of photographs and information on phasmids.
Stick Insects are usually thin like a twig, Leaf Insects are shaped like a leaf, together they are "phasmids" in the order of "phasmatodea". Like all insects, phasmids have six legs and three parts to their body: head, thorax, and abdomen. Some have wings but few can fly. They are usually in shades of brown and green. They vary in size from 12 mm (½ in) to over 356 mm (14 in). Their defence is usually their camouflage, but a few stick insects can spray an irritating spray, and some have one or more spurs on their legs which they sometimes dig into its attacker. Males are smaller than females, and often look either very similar to the females, or so different they seem like a different species.
The world’s biggest insect is a stick insect from Sabah: Chan’s Megastick (Phobaeticus chani), one specimen held in the Natural History Museum in London has a body length of 357 mm (14 in), and measures 567 mm (22.3 in) with outstretched legs. The heaviest known stick insect is the Jungle Nymph (Heteropteryx dilatata) at 51.2 g (1¾ oz).