These remarkable creatures are known as NEW GUINEA GIANT SPINY STICK INSECTS and come, as the name would suggest, from Papua New Guinea which is the large island to the north of Australia.  They can reach large sizes and as adults they are usually a beautiful and very dark brown or 'mahogany' colour, almost looking as if they have been polished like a piece of wooden furniture!  Here are some adult females looking particularly gorgeous:

Females of this particular species of stick insect are very easy to spot, even as juveniles, as they have a prominent spike at the end of their abdomen which is their ovipositor or egg-laying spike.  They use this to bury their ova (eggs) below the surface of the ground to protect the ova from animals which might otherwise eat them.

The males of this species are almost as large as the females and look quite similar, but of course they do not have an ovipositor.  Instead they have a very sharp spine on the 'thigh' part of each of their back legs, which they can and will use to defend themselves if they are disturbed or feel threatened.  The males are also able to produce a very unpleasant smell if they feel threatened, and this often causes potential predators to back away and decide against attacking them!

Despite their large size as adults, like most stick insects these start out in life as very small babies.  I have been fortunate to have had literally thousands of eggs from this species during my time keeping them and almost all of these have hatched!  Pictured below are two babies or nymphs next to a 10p coin, so you can see how small they are to start with!  What is even more amazing is that the babies each come out of a tiny egg, and there is one such egg at at the top left of the picture.  How such large babies can come out of such tiny eggs I don't think I will ever understand!

Even though the nymphs start out brown in colour, it is not long before they turn a lovely shade of mossy green, like those in the pictures below:

It is easy to tell the male and female nymphs apart in all three of the next pictures below, as the females (on the lower or left part of each picture) have the distinctive egg-laying spike (ovipositor) at the end of their abdomens!

As they continue to grow their colour gradually starts to change back to brown again, so in this way they end up going full circle from brown to green and back to brown again, before turning the beautiful mahogany colour of the adult female in the bottom picture when they are mature!