Sigaus
Sigaus of grasshoppers in the tribe Catantopini that isendemic to New Zealand, and all but one species is endemic to the South Island: Sigaus piliferus is the only North Island representative and is the type species. There are eight species in the genus; all are flightless, and many are coloured for camouflage against rocky ground.[2][3] Sigaus minutus and S. childi are threatened with extinction.[4]
| Sigaus | |
|---|---|
 | |
| Sigaus piliferus | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Insecta |
| Order: | Orthoptera |
| Suborder: | Caelifera |
| Family: | Acrididae |
| Tribe: | Catantopini |
| Genus: | Sigaus Hutton, 1897[1] |
| Species | |
|
Sigaus australis | |
Taxonomy
The taxonomy of New Zealand endemic grasshoppers was substantially revised by Bigelow in 1967, based mostly on female genitalia.[2] The genus Sigaus is distinguished from other New Zealand Acrididae by the distinctive structures of the internal male genitalia: the epiphallus lophi are saddle-like in shape with the mesal protuberance of the lophus having a smooth, rounded outline.[5] The genus is not however monophyletic with respect to other New Zealand grasshoppers.[6]
| Sigaus australis | Sigaus campestris | Sigaus childi | Sigaus homerensis | Sigaus minutus | Sigaus piliferus | Sigaus obelisci | Sigaus takahe | Sigaus villosus | |
|---|---|---|---|---|---|---|---|---|---|
| Photograph |  |  |  |  |  |  |  |  | |
| Elevation[7] | 1,300–1,700 m (4,300–5,600 ft) | 400–1,500 m (1,300–4,900 ft) | 200–500 m (660–1,600 ft) | 900–1,000 m (3,000–3,300 ft) | 300–800 m (980–2,600 ft) | 1,600–1,800 m (5,200–5,900 ft) | 1,000–1,400 m (5,900–6,900 ft) | 1,800–2,100 m (–6,900 ft) | |
| Described[8] | 1897[1] Hutton | 1897 Hutton | 1999[9] Jamieson | 2003[10] Morris | 1967[11] Bigelow | 1897 Hutton | 1967 Bigelow | 2003 Morris | 1950[12] Salmon |
| Habitat[13] | Tussock grasslands | Dry rocky hillsides/ tussock grasslands | Dry rocky hillsides | Tussock grasslands | Fluvial outwash | Tussock grasslands | Alpine lichen fields | Tussock grasslands | Scree |
| Polymorphism[14] | Highly cryptic | Highly cryptic | Highly cryptic | 2 | Highly cryptic | 2 | Highly cryptic | 1 | |
| Regions | Canterbury Otago | Canterbury Otago Southland | Otago | Southland | Canterbury | Waikato Gisborne Hawke's Bay Manawatū-Whanganui Wellington | Otago | Southland | Canterbury |
| Size[15] | Medium | Medium/large | Medium | Medium | Very small | Large | Large | Medium | Large |
| Status[16] | Not threatened | Not threatened | Nationally Critical | Range Restricted | Nationally Endangered | Not threatened | Range Restricted | Range Restricted | Not threatened |
| Wings[17] | Micropterous 2–3 mm | Micropterous 2–3 mm | Micropterous 1–2 mm | Micropterous 2–3 mm | Micropterous 1 mm | Micropterous 3–4 mm | Micropterous 3–4 mm | Micropterous 2–4 mm |
References
- Hutton, F.W. 1897: "The grasshoppers and locusts of New Zealand and the Kermadec Islands". Transactions of the New Zealand Institute 30: 135-50
- Bigelow, R.S. 1967. The Grasshoppers of New Zealand, Their Taxonomy and Distribution. University of Canterbury, Christchurch. p. 60.
- Jamieson, Colleen D. (1999). "A new species of Sigaus from Alexandra, New Zealand (Orthoptera: Acrididae)". New Zealand Journal of Zoology. 26 (1): 43–48. doi:10.1080/03014223.1999.9518176. ISSN 0301-4223.
- Trewick, S. A.; Morris, S. J.; Johns, P. M.; Hitchmough, R. A.; Stringer, I. A.N. (2012). "The conservation status of New Zealand Orthoptera". New Zealand Entomologist. 35 (2): 131–136. doi:10.1080/00779962.2012.686318. ISSN 0077-9962. S2CID 219564547.
- Morris, S.J. 2002: Identification guide to grasshoppers (Orthoptera: Acrididae) in Central Otago and Mackenzie Country. DOC Science Internal Series 26. Department of Conservation, Wellington. 17 p.
- Koot, Emily M.; Morgan-Richards, Mary; Trewick, Steven A. (2020). "An alpine grasshopper radiation older than the mountains, on Kā Tiritiri o te Moana (Southern Alps) of Aotearoa (New Zealand)". Molecular Phylogenetics and Evolution. 147: 106783. doi:10.1016/j.ympev.2020.106783. ISSN 1055-7903. PMID 32135305. S2CID 212567788.
- Species prefer altitude.
- The author and year the species was described.
- A new species of Sigaus from Alexandra, New Zealand (Orthoptera: Acrididae). New Zealand Journal of Zoology, 26: 43-48.
- Morris, S.J. 2003: "Two new species of Sigaus from Fiordland, New Zealand (Orthoptera: Acrididae)". New Zealand entomologist, 26: 65–74. PDF Archived 2011-07-21 at the Wayback Machine
- Bigelow, R.S. 1967: The Grasshoppers of New Zealand, Their Taxonomy and Distribution. University of Canterbury, Christchurch.
- Salmon, J.T. 1950: A new species of Acrididae (Insecta: Orthoptera) from New Zealand. Transactions of the Royal Society of New Zealand, Vol. 78, Part 1, page 69, February 1950
- Species prefer habitat.
- The number of colour morphs known for adults of this species.
- Size for adult males: Small less than 6 mm; Medium 6-30 mm & Large greater than 30 mm.
- Base on the New Zealand Threat Classification System
- Species wing length.
External links
- Sigaus discussed on RNZ Critter of the Week, 3 March 2017
- Citizen science observations in iNaturalist