Flax weevil

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Flax weevil
COLE Curculionidae Anagotus fairburni.png
Illustration by Des Helmore
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Coleoptera
Infraorder: Cucujiformia
Family: Curculionidae
Genus: Anagotus
Species:
A. fairburni
Binomial name
Anagotus fairburni
Brookes, 1932
New Zealand (relief map).png
Disc Plain red.svg
Manawatāwhi/Three Kings Islands
Disc Plain red.svg
Marlborough Sounds
Disc Plain red.svg
Te Puka-Hereka/Coal Island
Range of Anagotus fairburni in New Zealand

Anagotus fairburni or Flax weevil is a large flightless weevil. It feeds on leaves of New Zealand flax species where it produces a characteristic feeding notch. It is found on islands and in alpine areas of New Zealand.

Contents

Taxonomy and description

Flax weevil browsing on a flax flower Flax weevil on flower.jpg
Flax weevil browsing on a flax flower

The flax weevil was described by Albert E. Brookes in 1932 based on a series of specimens sent to him by Ernest Richard Fairburn. These were collected at its type locality of D'Urville Island in the Marlborough Sounds in 1931. The type specimen is held at the New Zealand Arthropod Collection. It was described as large and robust in form and ranging in size from 20–24mm. [1] Specimens can range in colour from coppery-brown to dark brown, or even black in older weevils that have lost their scales. They have distinctive pairs of tubercles mid-way along and at the base of the elytra. Larvae are large with a cream coloured body and brown head. The adult is flightless. [2]

Distribution and habitat

This species is distributed across a wide range. It can be located from the Three Kings Islands, north of the North Island of New Zealand, [2] to Coal Island in Fiordland [3] off the southern coast of the South Island. [4] Between these locations are numerous populations on islands in the Marlborough Sounds. On islands, it is usually found on New Zealand flax/harakeke ( Phormium tenax ). It is restricted to rodent-free islands and alpine areas. [2] [5] In the Tararua Range and on islands in Dusky Sound it lives on mountain flax/wharariki ( Phormium colensoi). [4] [6] All life cycle stages are found on or near flax.

Behaviour and host species

Flax weevil notches on flax leaves Flax weevil notch.jpg
Flax weevil notches on flax leaves

Adults are nocturnal and hide among the dead flax leaves at the base of a plant during the day, emerging at night to feed. Their feeding damage is smooth ovoid notching of the leaf edges; the asymmetrical notches are fibrous and rough, unlike the smooth notches left by the flax notch caterpillar Tmetolophota steropastis . [4] Eggs are deposited at the bases of leaves. [7] Larvae feed by burrowing into flax roots. [5] If disturbed at night, flax weevils characteristically drop from flax leaves onto the ground or stay motionless on leaves. [8]

Life cycle

Flax weevil on Te Pakeka/Maud Island Flax weevil.jpg
Flax weevil on Te Pākeka/Maud Island

White eggs are laid at the base of flax plants. These eggs can take from 3 to 5 weeks to develop into larvae. They gradually darken to a black colour prior to the larvae emerging. The yellow larvae move towards the fan of leaves near the plant base, where they tunnel into the soft tissue within. [9] The timing of the larval or pupal stages are unknown. Adult flax weevils have lived for over 12 months in captivity. [6]

Conservation and threats

The flax weevil is legally protected under Schedule 7 of the 1953 Wildlife Act, making it an offence to collect, possess or harm a specimen. [10] Predation by rats and mice has caused a restriction of their range to predator-free islands and alpine areas; historically, their range was throughout New Zealand. [8] Translocations have occurred to islands, once rodents have been removed. These include Breaksea Island in Fiordland, Titi Island in the Marlborough Sounds, and Mana Island off the south-west coast of the North Island. [11]

Research

Damage to flax plants is usually minimal, but on Mana Island the translocated population has caused the collapse and death of flax plants around the release site. The flax plants on Mana Island are being studied to see if they are more susceptible to flax weevil browsing, with field trials of flax plantings from different sources. [12] The absence of the fungus Beauveria was suggested as a reason for the lack of bio-control of flax weevils on Mana, but this entomopathogenic fungus turns out to be already present on the island. [13]

Related Research Articles

<span class="mw-page-title-main">Flax in New Zealand</span> Flax fibre (Phormium) in New Zealand

New Zealand flax describes the common New Zealand perennial plants Phormium tenax and Phormium colensoi, known by the Māori names harakeke and wharariki respectively. Although given the common name 'flax' they are quite distinct from the Northern Hemisphere plant known as flax .

<span class="mw-page-title-main">Takahē</span> Species of bird

The South Island takahē is a flightless swamphen indigenous to New Zealand and the largest living member of the rail family. It is often known by the abbreviated name takahē, which it shares with the recently extinct North Island takahē. The two takahē species are also known as notornis.

<span class="mw-page-title-main">Mana Island (New Zealand)</span> Island in New Zealand

Mana Island is the smaller of two islands that lie off the southwest coast of the North Island of New Zealand. The name of the Island is an abbreviation of the Maori name Te Mana o Kupe, which means "The Mana of Kupe".

<i>Aciphylla</i> Genus of flowering plants

Aciphylla is a genus of about 40 species of herbaceous plants in the family Apiaceae, all but two of them endemic to New Zealand. They range from small cushion plants to tall flower spikes surrounded by rosettes of stiff, pointed leaves, the latter probably adaptations to prevent browsing by moa. Their common name is speargrass or Spaniard. Most Aciphylla species live in subalpine or alpine habitats in the South Island. Fragrant oil extracted from some large species, known as taramea, is still used as a perfume by Māori.

<i>Dracophyllum</i> Genus of flowering plants

Dracophyllum is a genus of plants belonging to the family Ericaceae, formerly Epacridaceae. There are 61 species in the genus, mostly shrubs, but also cushion plants and trees, found in New Zealand, Australia, Lord Howe Island and New Caledonia. The name Dracophyllum, meaning dragon-leaf, refers to their strong outward similarity to the unrelated Dracaena, sometimes known as dragon tree. Although dicotyledonous, they resemble primitive monocots with their slender leaves concentrated in clumps at the ends of the branches; they are sometimes called grass-trees.

<i>Phormium colensoi</i> Species of flowering plant

Phormium colensoi, also called mountain flax, or wharariki in Māori, is a perennial plant that is endemic to New Zealand. The greenish, yellow or orange flowers are followed by twisted seed pods. It is less common than the other Phormium species, P. tenax or harakeke. Mountain flax is also called whararipi, whatariki, mangaeka, kōrari tuauru, wauraki, coastal flax, hill flax and lesser New Zealand flax.

<span class="mw-page-title-main">Māori traditional textiles</span> Indigenous textiles of the Māori people of New Zealand

Māori traditional textiles are the indigenous textiles of the Māori people of New Zealand. The organisation Te Roopu Raranga Whatu o Aotearoa, the national Māori weavers' collective, aims to preserve and foster the skills of making and using these materials.

<i>Phormium tenax</i> Species of flowering plant

Phormium tenax is an evergreen perennial plant native to New Zealand and Norfolk Island that is an important fibre plant and a popular ornamental plant. The plant grows as a clump of long, straplike leaves, up to two metres long, from which arises a much taller flowering shoot, with dramatic yellow or red flowers.

<i>Anagotus stephenensis</i> Species of beetle

Anagotus stephenensis, commonly known as the ngaio weevil, is a large flightless weevil that is only found on Stephens Island in New Zealand. The ngaio weevil was discovered in 1916 by A.C. O'Connor on Stephens Island. Thomas Broun described it in 1921 as Phaeophanus oconnori after its collector. The weevils were observed at the time to be 'feeding on tall fescue and the leaves of trees'.

<i>Phormium</i> Genus of flowering plants in the family Asphodelaceae

Phormium is a genus of two plant species in the family Asphodelaceae. One species is endemic to New Zealand and the other is native to New Zealand and Norfolk Island. The two species are widely known in New Zealand as flax or their Māori names wharariki and harakeke respectively, and elsewhere as New Zealand flax or flax lily, but they are not closely related to the Northern Hemisphere's flax, which is native to the region extending from the eastern Mediterranean to India and has been used by humans since 30,000 B.C.

<i>Aciphylla aurea</i> Species of flowering plant

Aciphylla aurea, known as taramea in Māori and golden speargrass or golden Spaniard in New Zealand English, is a large, spiky, tufted plant with sharp yellowish-green leaves in the speargrass genus Aciphylla. A. aurea is found throughout the South Island of New Zealand in montane to low alpine habitats.

<i>Ichneutica blenheimensis</i> Species of moth

Ichneutica blenheimensis is a species of moth in the family Noctuidae. It is endemic to New Zealand and is found throughout the North, South and the Stewart Islands. This species appears to prefer drier eastern localities and is rarely collected in western North Island forested areas. It does not appear to be frequently collected in inland dry tussock grassland habitats. The host plant for the larvae of this species is likely to be the golden sand sedge pīngao which is now absent from the moths type locality. However Chappell has raised very young larvae on grass species and the more developed larvae consumed Phormium tenax. Adults are on the wing from November to March and are attracted to both light and sugar traps. The blackish forewing fringes are diagnostic of this species. But worn specimens of I. arotis can be confused with worn specimens of I. blenheimensis. However I. arotis can be distinguished from I. blenheimensis as it has a scale-tuft on the thorax and dark longitudinal stripes on the tegula. This species is classified as "At Risk, Naturally Uncommon" by the Department of Conservation.

<i>Ichneutica steropastis</i> Species of moth endemic to New Zealand

Ichneutica steropastis, or the flax notcher moth, is a species of moth in the family Noctuidae. It is endemic to New Zealand and can be found throughout the country from the Three Kings Islands to Stewart Island as well as in the Chatham Islands. The larvae of this species feed on a variety of native and introduced plants however the New Zealand flax is one of the more well known host plants for the larvae of this moth. The larvae are nocturnal, hiding away in the base of the plants and coming out to feed at night. They create a distinctive notch in the leaf when they feed. The adults of this species are on the wing from October to March. Although adult specimens of I. steropastis are relatively easy to recognise they might possibly be confused with I. inscripta, I. theobroma or with darker forms of I. arotis. However I. steropastis can be distinguished as it has a long dark basal forewing streak that these three species lack.

<span class="mw-page-title-main">Anthony Whitaker</span> New Zealand herpetologist

Anthony Hume Whitaker was a New Zealand herpetologist, contributing a 50-year career of fieldwork, pioneering research and species discoveries. His is still the largest collection of reptile and amphibian specimens donated to Museum of New Zealand Te Papa Tongarewa.

<span class="mw-page-title-main">Turbott's weevil</span> Species of beetle

Turbott's weevil is a weevil that is endemic to New Zealand. It has been found on the Hen and Chicken Islands, the Poor Knights Islands and the Three Kings Islands.

<i>Hadramphus spinipennis</i> Species of beetle

Hadramphus spinipennis, commonly called the coxella weevil, is a large, nocturnal, flightless weevil only found on Mangere and Rangatira Islands in the Chatham Islands, New Zealand.

<i>Lyperobius huttoni</i> Species of beetle

Lyperobius huttoni is a New Zealand weevil found in alpine areas of the South Island and at sea level around the Wellington coast. It feeds only on speargrass (Aciphylla). Weevils from the endangered Wellington population have been translocated to predator-free Mana Island.

<span class="mw-page-title-main">Introduction of species to Mana Island</span> New Zealand ecological restoration programme

The New Zealand Department of Conservation has introduced a number of animal and plant species to Mana Island, near Porirua, New Zealand, as part of an ecological restoration programme since taking over conservation management of the island in 1987. Some were reintroductions of species wiped out during years of agricultural use or the subsequent explosion in the number of house mice on the island. A pest control programme eliminated the mice by 1990 and many species have been introduced since. Notable successes include the spotted skink, Duvaucel's gecko and the flax weevil, which are now regarded as well established, and the yellow-crowned parakeet, which has been described as abundant and widespread. Attempts have been made to introduce several seabird species in what the Department of Conservation describes as "the world's most complex seabird translocation project"; results have been mixed.

<i>Mentha cunninghamii</i> Species of mint

Mentha cunninghamii, known commonly as New Zealand mint or Māori mint, is a species within the Mentha (mint) genus, endemic to New Zealand.

<i>Dracophyllum fiordense</i> Species of flowering plant in the heath family Ericaceae

Dracophyllum fiordense, commonly known as the Fiordland grass tree, is a species of tree or shrub in the heath family, Ericaceae. It is endemic to the South Island of New Zealand. It reaches a height of 1.5–5.0 metres and has tufts of long green leaves at the ends of its branches. Each leaf has a distinctive curled spiral tip. D. fiordense has a pyramid-shaped inflorescence hidden under each clump of leaves, with between 113 and 120 pink flowers on each spike, and later reddish-brown dry fruit; both are around just 2 by 2 mm. It inhabits shrubland, lowland and subalpine forests, and tussock grassland of mountain slopes, gullies, and ridges. Its range covers two main areas: one in Fiordland National Park, and one in the Mount Cook and Westland National Parks.

References

  1. Brookes, A.E. (1932). "A new genus and six new species of Coleoptera". Transactions and Proceedings of the New Zealand Institute. 63: 25–33.
  2. 1 2 3 Marris, John (2001). Beetles of conservation interest from the Three Kings Islands: a report submitted to the Department of Conservation, Northland Conservancy (Report). hdl:10182/2996.
  3. Miskelly, Colin; Tennyson, Alan (2018-07-01). New locality records for two species of protected weevils, Anagotus fairburni (Brookes, 1932) and Hadramphus stilbocarpae Kuschel, 1971 (Coleoptera: Curculionidae), from southern Fiordland, New Zealand (Report). Vol. 29. pp. 20–34.
  4. 1 2 3 Miskelly, Colin (2016-12-14). "An inordinate fondness for weevils". Te Papa’s Blog. Retrieved 2019-03-28.
  5. 1 2 Miskelly, Colin (6 December 2017). "Further flax weevil finds from farthest Fiordland". Te Papa Blog. Retrieved 28 March 2019.
  6. 1 2 Meads, Mike (1990). Forgotten fauna : the rare, endangered, and protected invertebrates of New Zealand. Wellington: DSIR Pub. p. 42. ISBN   0477025900.
  7. McGuinness, CA (2001). "The conservation requirements of New Zealand's nationally threatened Invertebrates" (PDF). Retrieved 28 March 2019.
  8. 1 2 Miskelly, Colin (13 November 2013). "A plague of flax weevils – a conservation hyper-success story". Te Papa blog. Retrieved 28 March 2019.
  9. Gourlay, E.S. (1931). "A new and important flax-infesting weevil. Phaeophanus fairburni Brookes". N. Z. J. Sci. Technol. 13: 163–169.
  10. "Wildlife Act 1953". New Zealand Legislation. Retrieved 28 March 2019.
  11. "Reintroduction Specialist Group Oceania Section" . Retrieved 28 March 2019.
  12. Miskelly, Colin (2017). "Flax planting trials to assess flax weevil damage to plants of different provenances" (PDF). Retrieved 28 March 2019.
  13. Glare, Travis; Brookes, Jenny (November 2017). "Beauveria pseudobassiana and the Flax weevil from Mana Island" (PDF). Retrieved 28 March 2019.