Scarlet lily beetle

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Scarlet lily beetle
Scarlet lily beetles (Lilioceris lilii) mating.jpg
mating, Oxfordshire, UK
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Coleoptera
Infraorder: Cucujiformia
Family: Chrysomelidae
Subfamily: Criocerinae
Tribe: Criocerini
Genus: Lilioceris
Species:
L. lilii
Binomial name
Lilioceris lilii

The scarlet lily beetle, red lily beetle, or lily leaf beetle (Lilioceris lilii), is a leaf beetle that eats the leaves, stem, buds, and flowers, of lilies, fritillaries and other members of the family Liliaceae. It lays its eggs most often on Lilium and Fritillaria species. In the absence of Lilium and Fritillaria species, there are fewer eggs laid and the survival rate of eggs and larvae is reduced. [2] It is now a pest in most temperate climates where lilies are cultivated.

Contents

Description

This lily beetle belongs to the order Coleoptera, and the family Chrysomelidae, the leaf beetles. The adult lily beetle is about 6 to 9 mm (¼–⅜ in) in length, with relatively long legs and antennae. Its elytra (harder forewings) are bright scarlet and shiny. Its underside, legs, eyes, antennae and head are all black. It has large eyes, a slim thorax, and a wide abdomen. [3] Each antenna is made up of 11 segments. The eyes are notched and there are two grooves on the thorax. [4]

This lily beetle may be confused with the cardinal beetle (Pyrochroa serraticornis), which also has red elytra and a black underside. The wing cases of the lily leaf beetle are dimpled and are shinier and more rounded than those of the cardinal beetle, which are relatively dull, and narrower, flatter, and more elongated. The cardinal beetle also has comb-like antennae. [5] The lily leaf beetle is herbivorous, while the cardinal beetle preys on insects. [6] The lily leaf beetle is also confused with unspotted ladybirds, but it is narrower in shape. [3]

Natural history

Distribution

The lily leaf beetle is indigenous to parts of Europe and Asia. It is thought to have been introduced to North America through the importation of plant bulbs in 1943. [7] First spotted in Montreal, it spread throughout Canada and appeared in Massachusetts in 1992, and by 2012 was in all six New England States, as well as New York and Washington states. In Canada it is found from the Maritime Provinces west to Manitoba. [4] [7] As of 2001, it spread as far west as Alberta, and as of 2017 full infestations reported as far north as the Edmonton, AB area. It has also become established as an invasive species in the United Kingdom since being first recorded in 1839, although the first colony did not become established until 1939 and it did not spread far until the 1980s, then more rapidly from the 1980s. [8] [9] Since then it has spread from Surrey in southern England as far north as Inverness, Scotland. It is also found in Ireland. [8] It is also found in the Middle East and North Africa. [7]

Life cycle

Larvae eating lily leaf ScarletLilyBeetleLarvae.jpg
Larvae eating lily leaf

The beetle overwinters in the soil and emerges early in spring. The adult is generally found in moist, cool environments. [10] It emerges in spring to feed and mate. [3] The female can lay up to 450 eggs each season in batches of about 12 on the undersides of leaves. It arranges the red-orange to brown eggs in narrow irregular lines along the midrib, where they are more concealed. The eggs then hatch into yellow, brown or orange larvae in about 1–2 weeks. [7]

The larvae feed for up to 24 days, beginning underneath the leaf then working up the rest of the plant, and cause the most damage. Their preferred feeding locale is underneath the leaf or at the node where the leaf meets the stem. They then burrow in the ground to pupate in a cocoon of soil bound with saliva. In about 20 days they emerge as adults and continue to feed until winter. More than one cycle can occur in one year. [11] [7]

Behaviour

Often the first evidence of lily leaf beetle infestation is sticky brown frass piles containing larvae on leaves. The larvae remain in the frass for protection from the sun and predators. However, the fecal shield is not effective protection against parasitoids, and it may actually make it easier for parasitoids such as the wasp Lemophagus pulcher to locate the larvae. [12]

An adult that senses danger displays a defense mechanism, thanatosis, becoming motionless, folding up its appendages and falling with its black under surface facing up, thereby helping it camouflage with the ground to get away. If unable to escape, they are also able to ‘squeak’, by rubbing two parts of their body together, which may be used to startle the attacker. [13] This process is known as stridulation and could even shock a bird or any other predator that may attack the lily leaf beetle. [3]

Lilies may first show evidence of holes chewed in the leaves from consumption, and if left unchecked rapidly progress to blackening, and total loss of the leaves, leaving only the stem. Beetles and their larvae may also inhabit and devour the developing flower buds. Invasion may occur shortly after the new plants emerge from the soil, particularly if there are nearby Fritillaria which emerge earlier than Lilium. While Lilium and Fritillaria are affected, Hemerocallis is not. All types of lily may be affected, but while Asiatic lilies are the most vulnerable, some Oriental lilies may be more resistant. Resistant types include Lilium henryi 'Madame Butterfly', Lilium speciosum 'Uchida', and Lilium 'Black Beauty'. Other garden plants affected include Convallaria majalis , Polygonatum , potato ( Solanum tuberosum ), flowering tobacco ( Nicotiana ), hollyhock ( Alcea ) and Hosta . [7]

Pest impact

Adult eating lily leaf Scarlet lily beetle eating leaf.jpg
Adult eating lily leaf

Fritillaria and Lilium specimens in Canadian gardens, particularly around Halifax, Nova Scotia are significantly affected by the lily leaf beetle. A garden in Waverley, Nova Scotia has reported decline of lily species and cultivars from 50 in 1996 to only one in 2006. [14]

Control

The most surefire strategy for preventing infestation by any pest is to avoid planting susceptible plants in the first place, with lily beetle this necessitates avoiding growing so many desirable cultivars of Lilium, that other strategies may be preferred. Regular handpicking and crushing of eggs, larvae and adults is effective if somewhat laborious. Domestic insecticides registered for general leaf beetle control containing carbaryl, methoxychlor, malathion and rotenone can prove useful in controlling populations. [4] However, malathion and carbaryl, effective on adults and larvae, are toxic to bees and other insects, respectively. [15] Products based on neem extracts are useful in killing very young larvae and repelling adults without comparable harm to other insects, although this option is perhaps less effective than handpicking. Neem products should be applied every 5 to 7 days after egg hatch. Thiacloprid is also effective. [15] Floating row cover has been effective in preventing the adults from feeding and laying eggs in the spring. [16] [17]

Biological control

In Europe, total parasitism rate in the last instar stage averages about 90% on wild Lilium martagon , 75% in gardens and 60% in cultivated lily fields. Most lily leaf beetle parasitoids are wasps that lay eggs inside the host and effectively kill all infected individuals. Diaparsis jucunda (Ichneumonidae: Tersilochinae), dominates over 90% of the parasitoid infections in lily leaf beetle. However, in gardens and commercial fields, Tetrastichus setifer (Eulophidae: Tetrastichinae) and Lemophagus pulcher (Eulophidae: Campopleginae) become the dominant parasitoids in the later season. [18]

There are no natural predators or parasites of lily leaf beetle in North America. In 1996, University of Rhode Island began testing the effectiveness of biological control of lily leaf beetle using six natural parasitoids from Europe. CAB International Bioscience Switzerland Center has also participated in this project from 1998 till 2001. [18] The European parasitoid wasp Tetrastichus setifer was used in Massachusetts from 1999 to 2001; the experiment showed reduction of the beetle population. Population decline was also observed at another experiment site in Rhode Island. [19] In 2003, another parasitoid, Lemophagus errabundus, was released in Massachusetts and is now established in the region. [14] Similar parasitoid releases have been made in Boston with positive results. [20]

Related Research Articles

<i>Lilium</i> Genus of plants

Lilium is a genus of herbaceous flowering plants growing from bulbs, all with large prominent flowers. They are the true lilies. Lilies are a group of flowering plants which are important in culture and literature in much of the world. Most species are native to the Northern Hemisphere and their range is temperate climates and extends into the subtropics. Many other plants have "lily" in their common names, but do not belong to the same genus and are therefore not true lilies.

<span class="mw-page-title-main">Leaf beetle</span> Family of beetles

The insects of the beetle family Chrysomelidae are commonly known as leaf beetles, and include over 37,000 species in more than 2,500 genera, making up one of the largest and most commonly encountered of all beetle families. Numerous subfamilies are recognized, but the precise taxonomy and systematics are likely to change with ongoing research.

<span class="mw-page-title-main">Common asparagus beetle</span> Species of beetle

The common asparagus beetle is an important pest of asparagus crops both in Europe and in North America. Asparagus is its only food plant. The beetle is 6.0 mm to 9.5 mm long and slightly elongated. It is metallic blue-black in color with cream or yellow spots on its red-bordered elytra. The larvae are fat gray grubs with dark heads.

<span class="mw-page-title-main">Cereal leaf beetle</span> Species of beetle

The cereal leaf beetle is a significant crop pest, described by Carl Linnaeus in 1758.

<span class="mw-page-title-main">Cardinal beetle</span> Species of beetle

The name cardinal beetle typically refers to three different species of beetles. The red-headed or 'common' cardinal beetle is a red to orange beetle with, as the name suggests, a red head. It is about 20 millimetres (0.79 in) long, and is found throughout Britain. The rarer black-headed cardinal beetle, similarly found at sites across Britain, is larger and a deeper blood red. The scarce cardinal beetle also has a black head, but is smaller at around 9 millimetres (0.35 in) long. The scarce cardinal is only found at a few sites in Scotland and Wales.

<span class="mw-page-title-main">Chrysomelinae</span> Subfamily of beetles

The Chrysomelinae are a subfamily of leaf beetles (Chrysomelidae), commonly known as broad-bodied leaf beetles or broad-shouldered leaf beetles. It includes some 3,000 species around the world.

<i>Charidotella sexpunctata</i> Species of beetle

Charidotella sexpunctata, the golden tortoise beetle, is a species of beetle in the leaf beetle family, Chrysomelidae. It is native to the Americas, and very broadly distributed.

<span class="mw-page-title-main">Elm leaf beetle</span> Species of beetle

Xanthogaleruca luteola, commonly known as the elm-leaf beetle, is a beetle species in the family Chrysomelidae that is native to Europe but invasive in other parts of the world.

<i>Lilioceris merdigera</i> Species of beetle

Lilioceris merdigera is a species of beetle belonging to the family Chrysomelidae, subfamily Criocerinae.

<i>Spathius agrili</i> Species of wasp

Spathius agrili is a parasitic non-stinging wasp of family Braconidae which is native to North Asia. It is a parasitoid of the emerald ash borer, an invasive species which has destroyed tens of millions of ash trees in its introduced range in North America. As part of the campaign against the emerald ash borer (EAB), American scientists in conjunction with the Chinese Academy of Forestry began searching in 2003 for its natural enemies in the wild, leading to the discovery of several parasitoid wasp species, including Spathius agrili. S. agrili was discovered in Tianjin, China where it is a prevalent parasitoid of EAB larvae in stands of an introduced ash species, and an endemic ash species. S. agrili has been recorded to attack and kill up to 90 percent of EAB larvae.

<i>Fritillaria acmopetala</i> Species of plant in the family Liliaceae

Fritillaria acmopetala, the pointed-petal fritillary, is a species of flowering plant in the lily family Liliaceae, native to rocky limestone mountain slopes in the Middle East. It was described by the Swiss botanist Pierre Edmond Boissier in 1846.

<i>Chrysolina herbacea</i> Species of beetle

Chrysolina herbacea, also known as the mint leaf beetle, or green mint beetle, is a species of beetle in the family Chrysomelidae.

<i>Galerucella</i> Genus of beetles

Galerucella is a genus of leaf beetles in the family Chrysomelidae described by George Robert Crotch in 1873. It is widely distributed but absent in the Neotropics. Some species feed on waterlilies and are used as biocontrol of introduced, invasive waterlilies. Galerucella tenella feed on strawberry plants.

<i>Lilioceris</i> Genus of beetles

Lilioceris is a genus of beetles in the leaf beetle family, Chrysomelidae. The genus was first scientifically described in 1912 by Edmund Reitter. Lilioceris belongs to the subfamily Criocerinae and tribe Criocerini.

<i>Gratiana boliviana</i> Species of beetle

Gratiana boliviana is a species of beetle in the leaf beetle family, Chrysomelidae. Its common name is tropical soda apple leaf beetle. It is native to South America, where its distribution includes Argentina, Brazil, and Paraguay. It specializes on tropical soda apple, an invasive plant species. It has been released as an agent of biological pest control against the weedy plant in Florida and other parts of the United States.

<i>Chrysolina coerulans</i> Species of beetle

Chrysolina coerulans, also known as the blue mint beetle or blue mint leaf beetle, is a species of beetle in the family Chrysomelidae. It is in the subgenus of Synerga. It is native to a wide range of countries between mid and eastern Europe and lives alongside rivers and in meadows, it feeds on various plant members of the mint family.

<i>Phratora laticollis</i> Species of beetle

Phratora laticollis is a species of leaf beetle found in Europe and Asia. This beetle is found on Populus species and the chemistry and production of its larval defensive secretions and host plant relationships have been studied extensively.

Naomi Cappuccino is an associate professor of biology at Carleton University in Ottawa, Canada. Her research primarily focuses on population ecology and biological control of invasive species.

<i>Dicladispa armigera</i> Species of beetle

Dicladispa armigera is a species of leaf beetle from Southeast Asia, often known by its common name: the "rice hispa". These beetles are a well known invasive pest, and are responsible for significant crop damage across many countries. The male to female ratio is between 1:1.26 and 1:1.46.

Lemophagus pulcher is a species of insect in the family Ichneumonidae.

References

  1. Scopoli, I.A. (1763). Entomologia carniolica exhibens insecta carnioliae indigena et distributa in ordines, genera, species, varietates. Methodo Linnæana. Vindobonae [= Vienna]: Trattner. pp. [30] + 420 pp. Retrieved 23 June 2021.
  2. Ernst, Crystal; Cappuccino, Naomi; Arnason, John Thor (2007). "Potential novel hosts for the lily leaf beetle Lilioceris lilii Scopoli (Coleoptera: Chrysomelidae) in eastern North America". Ecological Entomology. 32: 45–52. doi:10.1111/j.1365-2311.2006.00834.x. S2CID   84675688.
  3. 1 2 3 4 Ernst, C. The Lily Leaf Beetle (Lilioceris lilii): an unwelcome invader. 2005 NALS Yearbook. North American Lily Society. pp. 29-34. Retrieved 2012-08-21.
  4. 1 2 3 "University of Guelph. Pest Diagnostic Clinic. Ian Smith: The Leaf Lily Beetle, 2003". Archived from the original on 2012-10-12. Retrieved 2012-08-21.
  5. "UK Safari. Lily Beetles" . Retrieved 2012-08-21.
  6. "Royal Horticultural Society. Red-headed cardinal beetle - Pyrochroa serraticornis" . Retrieved 2012-08-21.
  7. 1 2 3 4 5 6 Ann Whitman. Controlling Lily Leaf Beetles. Gardeners' Supply Company
  8. 1 2 "Lilioceris lilii (Scopoli, 1763) | BEETLES and BEETLE RECORDING in GREAT BRITAIN". www.coleoptera.org.uk. Retrieved 2016-01-18.
  9. "Learn more about lily beetle and how to help the RHS with research / RHS Gardening". www.rhs.org.uk. Retrieved 2016-01-18.
  10. Lily Leaf Beetle Lilioceris lilii. Archived 2013-06-16 at the Wayback Machine University of Rhode Island Landscape Horticulture Program Factsheets. 2002. Retrieved 2012-08-21.
  11. Shand 2008.
  12. Schaffner, U. and C. Muller. 2001. Exploitation of the fecal shield of the lily leaf beetle, Lilioceris lilii (Coleoptera: Chrysomelidae), by the specialist parasitoid Lemophagus pulcher (Hymenoptera: Ichneumonidae). Journal of Insect Behavior 14(6): 739-57.
  13. Biology of Leaf Beetles. Jolivet, P. Verma, K.K. 2002. Intercept. ISBN   9781898298861
  14. 1 2 Majka, C. G.; LeSage L. (2008). "Introduced leaf beetles of the Maritime Provinces, 5: the lily leaf beetle, Lilioceris lilii (Scopoli) (Coleoptera: Chrysomelidae)" (PDF). Proceedings of the Entomological Society of Washington. 110 (1): 186–195. doi:10.4289/0013-8797-110.1.186. S2CID   84398137 . Retrieved 16 March 2014.
  15. 1 2 "Manitoba Regional Lily Society". Archived from the original on October 6, 2006. Retrieved 2009-02-21.
  16. "Montréal Botanical Garden - Criocère du lis". Archived from the original on 2011-06-15. Retrieved 2009-02-21.
  17. "Gary Westlake. Lily Leaf Beetle. Peterborough Examiner" . Retrieved 2012-08-21.
  18. 1 2 "Kenis, M., Haye, T., Casagrande, R. A., Gold, M. S., and Tewksbury, L. A. Unspecified. Selection and importation of European parasitoids for the biological control of the lily leaf beetle in North America, and prospects for control in Europe. 1st International Symposium on Biological Control of Arthropods 1: 416-419" (PDF). Retrieved 2009-02-21.
  19. ""Biology and Control of the Lily Leaf Beetle." News & Views for New Hampshire's Green Industry. University of New Hampshire Cooperative Extension. April-June, 2005" (PDF). Archived from the original (PDF) on 2008-09-05. Retrieved 2009-02-21.
  20. "BBC - h2g2 - The Lily Leaf Beetle, 2007" . Retrieved 2009-02-21.

Bibliography