- Anoplophora chinensis, citrus longhorned beetle, is native to Asia and occurs primarily in China, Korea, and Japan.
- Life Cycle
- Larvae are white, opaque, legless grubs typical of longhorned beetles. When mature, they are 1.75-2.3 in. (4.4-5.8 cm) long and about 0.3 in. (0.8 cm) wide with an amber colored head and black mouthparts. Adults emerge from April to August. Adults are 1–1.5 in. (2.5-3.8 cm) long and shiny black with white markings. Antennae are at least as long as the body and have alternating black and white bands. The ventral surface is pubescent. The color of the pubescence varies from white to blue depending on location. An important identifying characteristic of Anoplophora chinensis is the presence of two pairs of polished white bumps at the base of the elytra. These are visible with a 10x hand lens and are not present on the Asian longhorn beetle, Anoplophora glabripennis. Damage includes distinct round or slightly oval shaped adult exit holes on the bark surface, T-shaped oviposition holes, sawdust-like frass or wood pulp around small holes, and larval tunnels in the wood under loose or thin bark.
- It has been found in, and eradicated from, Georgia, Wisconsin, and Washington. It was most likely introduced on wood packing material or in live plant material. It is known to attack and kill more than 100 species of plants and includes several species in the Citrus genus as well as peach, cherry, pecan, maple, oak, ash, elm, and walnut.
- Control Efforts
- Good sanitation such as burning or chipping infested plant parts, is always a good practice that can reduce populations of immature stages. The use of wire netting or spiral guards at the trunk base can serve as a physical barrier for oviposition. Remember that any suspect Anoplophora species may be a regulatory, actionable pest in the U.S. Contact your local state department of agriculture  for further information or questions regarding the status of this pest in your state. You should not attempt to control, manage, discard potentially infested wood material, or transport living plant material that you suspect may contain a regulatory pest.
The citrus longhorned beetle (CLB) was first intercepted during 2001 from a shipment of bonsai trees sent to a Washington nursery. After an eradication program that was immediately implemented, there have been no other reports.
- the Philippines
The host range of CLB includes over 100 plant species within 40+ plant genera. CLB is likely to become a pest of woody trees, woody ornamentals and natural areas.
Main Reported Hosts of Concern
- Citrus, including limes, lemons, oranges, and tangerines
- Trifoliate orange, Poncirus trifoliata
- Apple, Malus pumila
- Australian pine, Casuarina equisetifolia
- Poplars, Populus
- Willows, Salix
Additional Reported Hosts of Concern
|Acer, Maples||Albizzia, Silk tree|
|Alnus, Alders||Betula, Birch'|
|Camellia, Camellia||Carya, Hickory, Pecan|
|Castanea, Chestnut||Cryptomeria, Japanese cedar|
|Elaeagnus, Wild olive||Eriobotrya japonica, Loquat|
|Fagus, Beech||Ficus, Fig|
|Fortunella marginata, Kumquat||Fraxinus, Ash|
|Hibiscus, Hibiscus||Ilex, Holly|
|Juglans, Walnut||Lindera, Spicebush|
|Maackia, Amur||Morus, Mulberry|
|Photina, Christmas berry||Platanus, Sycamore, Plane Tree|
|Prunus, Cherry, Peach, Plum, Apricot||Pyracantha, Firethorn|
|Pyrus, Pears||Quercus, Oaks|
|Rhus, Sumac||Robina, Locust|
|Rosa, Rose||Rubus, Blackberry, Raspberry|
|Sophora, Pagoda tree||Styrax, Snowbell tree|
Description of Damage
CLB is of particular concern because it attacks apparently healthy trees. Most of the damage is caused by the larvae, which feed and tunnel within the woody portion of the host. The irregular tunnels caused larval burrowing interfere with the flow of xylem and phloem, and rapid tree decline is a subsequent result. Larval feeding wounds also increase the host's susceptibility to secondary pathogens. Adults may be seen feeding on the leaves, petioles, and bark, but do not cause serious damage.
Key Symptoms of Anoplophora infestation
- Presence of feeding adults on foliage
- Round exit holes, 6-11 mm, towards the base on the trunk
- Bleeding at oviposition, or egg laying, sites
- Frass at the base of an infested treee
- Swellings in the trunk where a possible pupal chamber might occur
In China, CLB emerges from April to August, but it is most abundant from May to July. The CLB life cycle is generally completed in one year. Adults feed and mate during the day. Eggs are laid by a T-shaped oviposition slit at the base of the trunk or exposed roots under the bark. According to Lieu (1945), an average of 15 eggs were laid under laboratory conditions, but other researchers have observed that a single female may lay up to 200 eggs.Larvae hatch within one to three weeks. The pupal stage lasts four to six weeks, and then an inactive pre-adult is formed. It takes about one or two weeks for the pre-adult to mature and emerge out of the tunnel.
Identification and Sample Submission Information
Although general information for all life stages is presented, the adult stage will be most definitive for identification purpose.
- 5.5mm (0.22 inches) long and 1.7 mm (0.07 inches) wide
- Creamy white to yellowish-brown, depending upon age
- 5 mm (0.2 inches) to 52 mm (2 inches)
- Creamy white, with some yellow patterns on prothorax
- 27-38 mm (1.15 inches) long
- 21-37 mm (up to 1.5 inches)
- Ten to twelve white spots on shiny black outer wing cover, or elytra
- Stout spine extends laterally from each side of the pronotum, or top surface of the prothorax
- Eleven segmented antennae marked with a white or light blue band near its base
- Elytra cover abdomen
- Narrow elytra
- Antennae twice as long as body
- Generally smaller than females
- Abdomen partially ocvers elytra
- Rounded elytra
- Antennae slightly longer than body
May be Confused With:
- Asian longhorned beetle
- Other Anoplophora
What to do with Suspect Anoplophora samples
All members of this genus are of potential concern from an emerging, invasive species perspective. Consult your local cooperative extension service, NPDN diagnostic lab, or state department of agriculture if you have detected a suspect sample.
There are some literature-based reports of management recommendations. In China weaver/red ants, Oecophylla smaragdina (Fab.) are effective predators of larvae. The fungi Beauveria brongniartii (Sacc.) has also been shown to cause high adult mortality. Good sanitation such as burning or chipping infested plant parts, is always a good practice that can reduce populations of immature stages. The use of wire netting or spiral guards at the trunk base can serve as a physical barrier for oviposition. Remember that any suspect Anoplophora species may be a regulatory, actionable pest in the U.S. Contact your local state department of agriculture  for further information or questions regarding the status of this pest in your state. You should not attempt to control, manage, discard potentially infested wood material, or transport living plant material that you suspect may contain a regulatory pest.
- Anonymous (2006) Citrus longhorn beetle (Anoplophora chinensis) Found at: http://www.defra.gov.uk/planth/pestnote/2006/citlong.pdf
- CABI. (2004). Crop Protection Compendium. Found at: http://www.cabicompendium.org/
- Chambers B. (2002). Citrus longhorned beetle program, King County, Washington: Environmental Assessment, April 2002. http://www.aphis.usda.gov/plant_health/ea/citrus_lb.shtml.
- Gyeltshen, J., and A. Hodges. 2005. Citrus Longhorned Beetle. Found at: http://creatures.ifas.ufl.edu/trees/beetles/citrus_longhorned_beetle.htm
- Lieu KOV. 1945. The study of wood borers in China -- I: Biology and control of the citrus-root-cerambycids, Melanauster chinensis, Forster (Coleoptera). The Florida Entomologist 27: 61-101.
- Lingafelter SW, Hoebeke ER. 2002. Revision of Anoplophora (Coleoptera: Cerambycidae). Entomological Society of Washington, Washington, DC. 236 pp. In: Gyeltshen, J., and A. Hodges. 2005.