Gromphadorhina oblongata, rare and exotic, These are said to be one of the largest of all of the Madagascar hissing cockroaches. Early in 2008 , they were so rare that 1 pair was $25 and almost impossible to get. They are still rare, but becoming more available. The larger adults are almost 4 inches and quite heavy. They are also docile enough to handle and calm down right way. They also have a mechanical comedy to them. Whenever I bring someone into "the bug room" I show them this roach. They are always a hit! They are also a long lived insect that may live 4 to 5 years or more, which is quite long for an insect. The madagascar hissers are also the only insects in the world that make a sound other than a rubbing of body parts ,like a wing or leg. They actually blow air through a tube to make the loud hissing noise. The males have horns on thier thorax that is used in territorial ritual. I have witnessed their jousting with each other to see which of them is worthy of the females affections. I also saw one male practicing on a light bulb, I could not help but chuckle . So if you are in the market for a unique pet that would be great on a desk at work or home as well as a fine class project at school then buy madagascar hissing roaches, you will be entertained.