Zorion opacum
| Zorion opacum | |
|---|---|
Naturally Uncommon (NZ TCS) | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Insecta |
| Order: | Coleoptera |
| Suborder: | Polyphaga |
| Infraorder: | Cucujiformia |
| Family: | Cerambycidae |
| Genus: | Zorion |
| Species: | Z. opacum
|
| Binomial name | |
| Zorion opacum Sharp, 1903
| |
Zorion opacum are a species of longhorn beetle endemic to the Chatham Islands of New Zealand. They were first formally described in 1903 by David Sharp. They are distinguished from other Zorion by their silky dull appearance. Adults occur from early November to early March, the warmer months in the southern hemisphere. The adults feed on pollen whereas the larvae feed on bark and trunks of plants. Under the New Zealand Threat Classification System, they are listed as "Naturally Uncommon".
Taxonomy
This species was first described in taxonomic literature in 1903 by David Sharp from three specimens collected by Hugo Schauinsland. Sharp noted there was also a specimen collected from Otago, but found this to be questionable.[1] In an 1897 paper, Frederick Hutton reported the occurrence of Zorion minitum in the Chatham Islands, but this was probably Z. opacum.[2][3] It was most recently revised in 2005, during which it was given an updated description. The lectotype (a specimen chosen to serve as the type specimen when the original describer didn't give one) is stored in the Natural History Museum, London.[4]
Z. opacum are members of the genus Zorion, which are composed of ten species, all of which are restricted to New Zealand. They are members of the tribe Aphneopini, which are broadly referred to as "flower longhorn beetles".[4]
Description
As adults, the males are 3.18-6.96mm in length whereas the females are 3.78-7.12mm. The body texture has a silky dull appearance, which distinguishes it from the other known Zorion species. The base colour of the body is golden-brown, with the elytra (modified forewings that cover the abdomen) having a pair of small pale spots on them.[4]
Distribution and habitat
They are endemic, or restricted to, the Chatham Islands in New Zealand. They have been found on Chatham Island and Pitt Island, as well as some of the smaller surrounding islands. They are associated with forest, shrub, bush and broadleaf habitat. They have been found on several native plant species such as Coprosma, Muehlenbeckia australis and Plagianthus regius.[4] They have also been recorded on blackberry.[5]
Life history
Adults have been recorded between early November and early March (warmer months). Rearing records of collected larvae have reported females taking 216-245 days to mature whereas male took 216-245 days. Like other Zorion, the adults feed on pollen whereas the larvae are known to feed on the bark and trunks of plants. The larvae have been successful reared to maturity from plants endemic to the Chatham Islands such as Veronica barkeri, Myrsine chathamica, Myrsine coxii and Plagianthus.[4]
Conservation status
Under the New Zealand Threat Classification System, this species is listed as "Naturally Uncommon" with the qualifiers of "Range Restricted" and "Island Endemic". This is due to the species only occurring on the Chatham Islands.[6]
References
- ^ Sharp, David (1903). "Some new Coleoptera from the Chatham Islands and New Zealand". Entomologist's Monthly Magazine. 39: 109.
- ^ Hutton, Frederick W (1898). "On a collection of insects from the Chatham Islands with descriptions of three new species". Transactions and Proceedings of the New Zealand Institute. 30: 158.
- ^ Emberson, Rowan M. (1998). "The beetle (Coleoptera) fauna of the Chatham Islands". New Zealand Entomologist. 21 (1): 25–64. doi:10.1080/00779962.1998.9722037. ISSN 0077-9962.
- ^ a b c d e Schnitzler, Franz-Rudolf; Wang, Qiao Wang (2005). "Revision of Zorion Pascoe (Coleoptera: Cerambycidae), an endemic genus of New Zealand". Zootaxa. 1066 (1): 1–42. doi:10.11646/zootaxa.1066.1.1. ISSN 1175-5334.
- ^ Macfarlane, Rod P (1979). "Notes on insects of the Chatham Islands". New Zealand Entomologist. 7 (1): 67.
- ^ Leschen, R. A.B.; Marris, J. W.M.; Emberson, R. M.; Nunn, J.; Hitchmough, R. A.; Stringer, I. A.N. (1 July 2012). "The conservation status of New Zealand Coleoptera". New Zealand Entomologist. 35 (2): 91–98. doi:10.1080/00779962.2012.686311. ISSN 0077-9962.