tree weta
 
 

Tree weta (Hemideina) are those most commonly encountered in suburban settings in the North Island. They are up to 40 mm long and most commonly live in holes in trees formed by beetle and moth larvae or where rot has set in after a twig has broken off. The hole, called a gallery, is maintained by the weta and any growth of the bark surrounding the opening is chewed away.

There are seven species of tree weta:
- Hemideina thoracica (Auckland tree weta) occurs in northern and central North Island, south to Hawke's Bay and the Manawatu
- H. crassidens (Wellington tree weta) is distributed in southern North Island and northern parts of South Island, and the West Coast.
- H. trewicki (Hawke's Bay tree weta), is restricted to the southern Hawke's Bay where it's range partially overlaps with Auckland tree weta.
- H. femorata occurs in Marlborough and Canterbury.
- H. ricta is restricted to Banks Peninsula.
- H. broughi (West Coast bush weta) has a range that overlaps with the Wellington tree weta in Nelson and the northern portion of the West Coast area.
- H. maori, the mountain stone weta, lives in the drier areas of the South Island high country from the Kaikoura Ranges south to Rock and Pillar Range In Otago. Unlike other species it usually live on the ground under stones or in crevices, above the tree line.

wellington tree weta Hemideina femorata Hemideina thoracica
H. crassidens male H. femorata female H. thoracica male
Hemideina trewicki H ricta Hemideina maori
H. trewicki male H. ricta female H. maori male

 

Tree weta (Hemideina) species identification key*:

1. Jaw ridges present Yes.............................H. femorata No.................................go to 2
2. Stridulatory ridges present Yes.............................go to 3 No.................................H. broughi
3. Number of stridulatory ridges <16.............................go to 4 >16...............................go to 6
4. Striped abdomen (prominant dark and light colour stripes)? Yes.............................go to 5 No................................H. thoracica
5. Pronotum dark or light coloured? Dark coloured..........H. crassidens Light coloured with or without few dark blobs...........................H. trewicki
6. Striped abdomen (prominant dark and light colour stripes)? Yes............................H. maori No..............................H. ricta

*Alternatively, possible tree weta species could be worked out through the location guide below. However in certain localities, 2 or more tree weta species co-occur and in that case, the above key has to be used in combination with the location guide.


Distribution
tree weta map H. trewicki H. femorata H. ricta