Taxonomy
Titanus giganteus: female, collection specimen © Natural History Museum, London
The species was first described by Carolus Linnaeus in 1771.
Beetle, not cockroach!
When they first see it, many people think that Titanus giganteus looks like an enormous cockroach, because of its:
- flattened body
- long, relatively soft wing cases
- long spiny legs
- long antennae
Nothing could be further from the truth. Titanus is a true beetle, belonging to a group called the holometabolous insects - insects which have a distinct larval and pupal stage in their development. The group also includes:
- butterflies
- flies
- wasps
- bees
In contrast, a cockroach is a hemimetabolous insect - immature forms look, and live, like miniature versions of the adults. Other hemimetabolous insects include:
- grasshoppers
- crickets
- greenflies
- earwigs
The 2 groups are only distantly related and they separated hundreds of millions of years ago. Any resemblance that this giant beetle has to a cockroach is entirely superficial, probably because both insects evolved in similar environments, pushing through tropical forest leaf-litter.
Unlike Titanus though, some cockroaches have also adapted to live in our houses!
