Insect Identification logo
Icon of the state of Texas
Icon of a spider
Icon of a beetle insect
Icon of a butterfly
Icon of a bee
Icon of the Bugfinder utility

Asian Horntail (Eriotremex formosanus)


Detailing the physical features, habits, territorial reach and other identifying qualities of the Asian Horntail.

 Updated: 6/11/2019; Authored By Staff Writer; Content ¬©www.InsectIdentification.org




Fine hairs on the Asian Horntail and a host plant preference diet separate it from other horntails.



The Asian Horntail was accidentally imported in the 1970s where it was likely embedded in wood as larvae and pupae when it was shipped from Asia. It is most commonly found in the coastal states of the southeastern U.S. where it rapidly expanded upon arrival, though it was reported in Utah, too. It is not considered a serious pest thanks to its use of trees that are already dead or dying. Unlike other horntails, this species prefers to use deciduous trees as host plants instead of conifers. Oak, sweetgum, and hickory trees are common hosts. Though the Asian Horntail does not attack healthy trees, care is being taken to discourage its expansion across the region. It does not have any known predators that could help control its numbers should the insect ever change how it chooses host plants. For now, slowing the spread of the Asian Horntail by teaching prudent firewood practices is underway. Little is known about its life history despite decades of its presence in North America.

The appearance of the female Asian Horntail is unique. Males are rarely seen and may have variations in how much yellow color they have on their bodies. Unlike native horntails, the female's abdomen has a ring of fine hairs that encircle it. The long black abdomen has yellow rings on it. More fine hairs may also cover other parts of the body. A bright yellow thorax sits just behind the head. Legs have wide yellow and black bands on them. Her thick ovipositor at the tip of the abdomen looks like a syringe, and she uses it to inject fertilized eggs into trees. Like other horntails, the larvae likely tunnel in or around the wood inside as they grow.
Flying insect icon
Hairy insect icon
Striped or banded insect icon




Taxonomic Hierarchy
Kingdom: Animalia
  Phylum: Arthropoda
    Class: Insecta
      Order: Hymenoptera
        Family: Siricidae
          Genus: Eriotremex
            Species: formosanus
Identifying Information
Scientific Name: Eriotremex formosanus
Category: Bee, Ant, Wasp and Similar
Size (Adult; Length): 28mm to 30mm (1.09in to 1.17in)
Colorwheel Graphic Colors: black, yellow, red
Descriptors: hairy, tail, hairs, flying, big, banded, tinted wings
Territorial Map
Alaska  
Hawaii  
Prince Edward Is.  
State of Alabama graphic
State of Arizona graphic
State of Arkansas graphic
State of California graphic
State of Colorado graphic
State of Delware graphic
State of Florida graphic
State of Georgia graphic
State of Idaho graphic
State of Illinois graphic
State of Indiana graphic
State of Iowa graphic
State of Kansas graphic
State of Kentucky graphic
State of Louisiana graphic
State of Maine graphic
State of Maryland graphic
State of Michigan graphic
State of Minnesota graphic
State of Mississippi graphic
State of Missouri graphic
State of Montana graphic
State of Nebraska graphic
State of Nevada graphic
State of New England graphic
State of New Jersey graphic
State of New Mexico graphic
State of New York graphic
State of North Carolina graphic
State of North Dakota graphic
State of Ohio graphic
State of Oklahoma graphic
State of Oregon graphic
State of Pennsylvania graphic
State of South Carolina graphic
State of South Dakota graphic
State of Tennessee graphic
State of Texas graphic
State of Utah graphic
State of Virginia graphic
State of Washington graphic
State of West Virginia graphic
State of Wisconsin graphic
State of Wyoming graphic
Canadian territory of Alberta graphic
Canadian territory of British Columbia graphic
Canadian territory of Manitoba graphic
Canadian territory of New Brunswick graphic
Canadian territory of Newfoundland and Labrador graphic
Canadian territory of Ontario graphic
Canadian territory of Quebec graphic
Canadian territory of Saskatchewan graphic
Territory map graphic of the country of Mexico
Contiguous United States shape map layer graphic




Territorial Reach (A-to-Z)
Alabama
Alaska
Arizona
Arkansas
California
Colorado
Connecticut
Delaware
Florida
Georgia
Hawaii
Idaho
Illinois
Indiana
Iowa
Kansas
Kentucky
Louisiana
Maine
Maryland
Massachusetts
Michigan
Minnesota
Mississippi
Missouri
Montana
Nebraska
Nevada
New Hampshire
New Jersey
New Mexico
New York
North Carolina
North Dakota
Ohio
Oklahoma
Oregon
Pennsylvania
Rhode Island
South Carolina
South Dakota
Tennessee
Texas
Utah
Vermont
Virginia
Washington
West Virginia
Wisconsin
Wyoming
Canadian National Flag Graphic
Alberta
British Columbia
Manitoba
New Brunswick
Newfoundland and Labrador
Nova Scotia
Ontario
Prince Edward Island
Quebec
Saskatchewan
Mexican National Flag Graphic
Mexico
Note: An insect's reach is not limited by lines drawn on a map and therefore species may appear in areas, regions and/or states beyond those listed above as they are driven by environmental factors (such as climate change), available food supplies and mating patterns. Grayed-out selections indicate that the subject in question has not been reported in that particular territory. U.S. states and Canadian provinces / territories are clickable to their respective bug listings.




Ant, Bee, and Wasp Anatomy
Graphic showing basic anatomy of both a bee and an ant insect
1
Antennae: Ants and Bees both have a pair of antennae on the head that senses their surroundings.
2
Head: The head contains the insect's compound eyes, antennae, and mandibles.
3
Thorax: Contains various vital parts such as the aorta and nervous system.
4
Abdomen: Contains various organs including the heart, gut, venom glands, and anus.
5
Legs: Ants and Bees have three pairs of legs attached to the thorax (center-body section).
NOTE: Ants, Bees and Wasps are part of the Hymenoptera order because they share many similarities.