One day , nearly 140 million years ago, towards the end of the Jurassic epoch, a male locust was blown offshore from the Australia-Antarctic coast of Gondwana in a westerly storm. Or perhaps it was carried out to sea in a volcanic ash cloud, or maybe it was just trying to emigrate.
Whatever the case, perhaps 50 km offshore, exhausted, it fell into the sea and was no doubt snapped up by a passing fish—except for its left wing, which was torn off and settled slowly through the water to the muddy seafloor a couple of hundred metres below.
That wing, now just a faint imprint in a rock, was found in 1978 by two students from the University of Auckland Geology Department during its annual field mapping camp for second year students south of Port Waikato.
Fossil insects are rare in New Zealand rocks, and because this wing is the oldest so far known, its correct identification was a matter of significance. After being examined by experts in England and Australia, the species has now been named Notohagla mauii, “Maui’s southern locust,” and its taxonomic relationships analysed.
The pattern of veins on the wing places its owner in the family Prophalangopsidae, which was erected for a single species of living “primitive” locust from India. A variety of central Asian fossil insects of Jurassic-Cretaceous age (190-65 million years ago) that once lived on that portion of the great old southern continent Gondwana, have since been placed in the family.
No prophalangopsid other than Notohagla is known from the Southern Hemisphere. However, wetas, a large group which also has a gondwanan distribution (southern Africa, Madagascar, south-east Himalaya, Australia, New Caledonia and Chile as well as New Zealand), are regarded as being closely related to the prophalangopsids.
A modern Australian winged weta has vein patterns closely similar to those of various Jurassic prophalangopsids, and this modern weta also possessses an area of small tubercles on the upper surface of the wing that is matched in Notohagla.
All of this suggests that our unique flightless wetas may have originated from prophalangopsids via an insect such as Notohagla.