What are weta? GONDWETA (detailed)
What are weta?
Weta is the Maori name given to genera from both the families Anostostomatidae and Rhaphidophoridae (cave weta). They are Orthopteran insects related to King crickets and their allies. They have some of the most fascinating characters known for insects such as enlarged heads which can be asymmetrical (one side of the head is larger than the other!), enlarged mandibles (jaws) and strong jumping back legs. Some species have a fascinating arsenal of weaponry including tusks, mandibular extensions and/or leg spins.
Courting rituals are unusual for Orthoptera and the placement of the ‘nuptial gift’ is also interesting. Males provide their female mates with a nuptial gift but unlike most Orthoptera it is separated into two parts, the sperm amuplla (contains sperm) and the spermatophylax (nuptial meal eaten by the female) (Gwynne, 2002). In one species of ground weta (Hemiandrus pallitarsis) there is an unusual lobed clasp on the 6th abdominal sternite of females which function is still unknown (see photo below right-the bilobed structure on the underside of the abdomen). This species has also been observed to provide maternal care (Gwynne, 2004), tending to both eggs and young (nymphs) inside their brood chamber (burrow) which is highly unusual for Orthoptera. 
Where are weta found?
Generally weta is a New Zealand term, however close relatives of these families can be found throughout the world. Anostostomatids have representatives in Australia, New Caledonia, Papua New Guinea, South Africa, South America, Madagascar, India and reportedly China. This largely southern Hemisphere distribution raises the idea that these insects were around before the supercontinent Gondwana began to break apart approximately 160 million years ago (MYA). It is thought that New Zealand and New Caledonia rifted away from Gondwana approximately 80 MYA and subsequently separated from each other between 40-70 MYA. If this is shown to be important in the evolutionary history of weta (ie. if they were isolated by this vicariant event with no subsequent dispersal) we can hypothesise that New Zealand and New Caledonian genera will be more closely related to each other than to any other genera from the Gondwanan fragments.
My focus is on the family Anostostomatidae as it is believed that they have existed relatively unchanged since the Mesozoic (there are reports of fossils, but I would like to see them before I pass judgment!). I want to investigate the relationships both within New Zealand and compare the New Zealand genera (Deinacrida, Hemideina, Motuweta, Anisoura and Hemiandrus) to their relatives in the rest of the world. I aim to answer questions relating to their taxonomy and determine timing and stimulus for speciation.
Currently I am working on a number of mini projects including New Zealand only relationships, Australasian relationships (New Zealand, New Caledonia and Australia) and ‘Gondwanan’ relationships (Australasia, South Africa and South America) sequencing different genes of both mitochondrial and nuclear genomes. Different genes are used as they give different levels of information which tell you about the evolutionary history of the organism ie. certain genes are known to evolve slowly (accumulate mutations in the sequence) while others evolve quickly. 
I am currently using the mitochondrial genes; Cytochrome oxidase I and II (COI and COII) and the ribosomal subunits 12S and 16S. The nuclear gene that I have successfully used to date is the ribosomal subunit 18S however I am looking at using Elongation factor 1-alfa (EF1α) and researching other potentially useful genes. I am also developing methods and primers suitable for amplification of the whole mitochondrial genome. I aim to sequence at least one whole mitochondrial genome for the family.
New Zealand photo gallery
ANOSTOSTOMATIDAE IN NEW ZEALAND
Many species are rare and endangered in New Zealand. Giant weta (Deinacrida) and Tusked weta (Motuweta/Anisoura) are predominantly found on small offshore islands with a few populations still surviving on the mainland. The decline in numbers is believed to be related to introduced pests (eg. rats and mice) and habitat destruction. Tree weta (Hemideina) and Ground weta (Hemiandrus) are common and can be found feeding in trees at night (they are all nocturnal insects), on the ground, in logs and under rocks. Basic information on their distribution, abundance, ecology and behaviour is still relatively limited.
Habitats:
Anostostomatidae can be found in various habitats ranging from alpine areas to your urban garden! They are adapted to night life in the trees, underground and in caves. During the day you can find weta by turning over rocks and logs however if you want to see what they really get up to the best time to spot them is at night.
Diet:
Most genera are classified as omnivorous (feeding on both protein and vegetable matter) known to eat other insects, dead animals, each other (if kept together!!) as well as fungi, fruit and leaves. The giant and tree weta are thought to be predominantly herbivorous which is unusual for Orthopterans.
Fun Facts:
Ground weta (Hemiandrus) have no ears! Other weta have their ears on their front legs.
The largest giant weta weighs approximately 70grams and is approximately 8.5cm (excluding the ovipositor).
Ovipositors have been mistaken to be stings….they actually are harmless. Ovipositors are hollow shafts used to deposit eggs into the soil. The picture below (right) shows a 'long' ovipositor from the ground weta H. maculifrons. Ovipositors length varies in the genus Hemiandrus; long, medium and short. 
Weta means both singular and plural but sometimes an ‘s’ is added in English literature
Grants:
The Orthopterists’ Society has awarded me a travel grant to visit New Zealand’s resident expert Peter Johns in Christchurch. By working closely with an expert in taxonomy I aim to improve my morphological identification ability, and to obtain samples of many of the undescribed Ground weta (Hemiandrus) species.
For more detail on New Zealand's Anostostomatidae taxonomy.
For more detail on world wide Anostostomatidae taxonomy.
References:
Gwynne, D. T. 2004. Reproductive behaviour of ground weta (Orthoptera: Anostostomatidae): Drumming behaviour, nuptial feeding, post-copulatory guarding and maternal care, Journal of the Kansas Entomological Society, 77(4):414-428.
Gwynne, D. T. 2002. A secondary copulatory structure in a female insect: a clasp for a nuptial meal? Naturwissenschaften 89:125-127.