Schiefer and Bright (2004) provide a thorough detailed description of the female. The males are relatively scarce. In comparison with other members of the tribe Xyleborini, X. mutilatus is relatively large at 3.46-3.88 mm long (Schiefer and Bright, 2004). The adult beetles are black, with reddish-brown legs and antennae. The elytra are 0.78 times longer than they are wide (Schiefer and Bright, 2004) and appear shorter than the pronotum, making them readily recognisable (Thomas, 2007). In dorsal view, the head is completely hidden by the pronotum, which is 0.86 times longer than it is wide and 1.11 times longer than the elytra (Schiefer and Bright, 2004;Coyle, 2006). The antennal club is round and appears to be obliquely cut (Coyle, 2006;Thomas, 2007). The body is generally smooth and shining (Coyle, 2006), with a long, golden and moderately dense pubescence on the abdomen (Schiefer and Bright, 2004).
Ambrosia beetles construct galleries (tunnels) in the xylem wood of their host plants, wherein the adults and larvae will be found with their fungal associates and accompanying staining of the wood. External evidence of Xylosandrus presence will be pin-hole sized entrance wounds in the bark that may be either bleeding or contain a light colored boring dust. There may be tooth-pick-like curling frass at the entrance holes (Rabaglia, 2003). Attacked plants may be wilting, exhibiting twig dieback, or dead. Often such plants are of small diameter, less than 5 cm.
Related invasive species
- Xylosandrus mutilatus
Related Farm Practice
- Comparisons
- Cuttings
X. mutilatus is a polyphagous ambrosia beetle, of possible relevance as a pest, that is indigenous to at least 10 countries in eastern and southern Asia (Japan to India). It has been recently discovered (1999) in the warm temperate, southeastern United States (Alabama, Georgia, Florida, Mississippi, Tennessee, and Texas), the only region occupied outside of its native Asian range. In northern Mississippi, it has multiplied prolifically and appears therefore highly capable of surviving and spreading in its newly adopted territory.
In its natural range, reported hosts of X. mutilatus are as follows (Schiefer and Bright, 2004): Acer spp. Acer sieboldianum Albizia spp. Benzoin [ Lindera ] spp. Camellia spp. Carpinus laxiflora Castanea spp. Cinnamomum camphora Cornus spp. Cryptomeria japonica Fagus crenata Lindera erythrocarpa Lindera triloba Machilus thunbergii [ Persea thunbergii ] Ormosia hosiei Osmanthus fragrans Parabenzoin praecox [ Lindera praecox ] Platycarya spp. Swieitenia macrophylla.
In North America, reported hosts of X. mutilatus are as follows (Stone et al., 2007):
Acer palmatum Acer rubrum Acer saccharum Carya spp. Juglans nigra Liquidambar styraciflua Liriodendron tulipifera Melia azedarach Ostrya virginiana Pinus taeda Prunus serotina Prunus americana Ulmus alata
Vitus rotundifolia.
Host Plants and Other Plants Affected
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Plant name|Family|Context
Acer (maples)|Aceraceae
Acer palmatum (Japanese maple)|Aceraceae
Acer rubrum (red maple)|Aceraceae
Acer saccharum (sugar maple)|Aceraceae
Acer sieboldianum|Aceraceae
Albizia|Fabaceae
Camellia|Theaceae
Carpinus laxiflora|Betulaceae
Carya (hickories)|Juglandaceae
Castanea (chestnuts)|Fagaceae
Cinnamomum camphora (camphor laurel)|Lauraceae
Cornus (Dogwood)|Cornaceae
Cryptomeria japonica (Japanese cedar)|Taxodiaceae
Fagus crenata (Japanese beech)|Fagaceae
Juglans nigra (black walnut)|Juglandaceae
Lindera (spicebush)|Lauraceae
Lindera erythrocarpa|Lauraceae
Lindera praecox|Lauraceae|Unknown
Lindera triloba|Lauraceae
Liquidambar styraciflua (Sweet gum)|Hamamelidaceae
Liriodendron tulipifera (tuliptree)|Magnoliaceae
Melia azedarach (Chinaberry)|Meliaceae
Ormosia hosiei|Fabaceae
Osmanthus fragrans|Oleaceae
Ostrya virginiana (American hophornbeam)|Betulaceae
Persea thunbergii|Lauraceae
Pinus taeda (loblolly pine)|Pinaceae
Platycarya|Juglandaceae|Unknown
Prunus americana (American plum)|Rosaceae
Prunus serotina (black cherry)|Rosaceae
Swietenia macrophylla (big leaved mahogany)|Meliaceae
Ulmus alata (Winged elm)|Ulmaceae
Vitis rotundifolia (Muscadine grape)|Vitaceae
List of Symptoms/Signs
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Sign|Life Stages|Type
Stems / dieback
Stems / discoloration
Stems / internal discoloration
Stems / internal feeding
Stems / mycelium present
Stems / necrosis
Stems / ooze
Stems / visible frass
Whole plant / discoloration
Whole plant / frass visible
Whole plant / internal feeding
Whole plant / plant dead;dieback
Biology and Ecology
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X. mutilatus is univoltine. Adult females make dispersal flights from June to August, seeking small diameter hosts in which to establish a gallery in the wood. Reported host plants in its natural range include Acer spp., Acer sieboldianum, Albizia spp., Benzoin [ Lindera ] spp., Camellia spp., Carpinus laxiflora, Castanea spp., Cinnamomum camphora, Cornus spp., Cryptomeria japonica, Fagus crenata, Lindera erythrocarpa, Lindera triloba, Machilus thunbergii [ Persea thunbergii ], Ormosia hosiei, Osmanthus fragrans, Parabenzoin praecox [ Lindera praecox ], Platycarya spp., and Swieitenia macrophylla (Schiefer and Bright, 2004). In North America its reported hosts thus far include Acer rubrum, Acer saccharum, Acer palmatum, Carya spp., Liriodendron tulipifera, Liquidambar styraciflua, Melia azedarach, Ostrya virginiana, Pinus taeda, Prunus serotina, Prunus americana, Ulmus alata, and Vitus rotundifolia (Stone et al., 2007). The gallery system excavated in the xylem is inoculated with spores of several species of ambrosia fungi (Kajimura and Hijii, 1992;Stone et al., 2005) carried in mycangia, a pair of dorsally located pits between the pronotum and mesonotum. As many as 38 eggs (average is 10) are laid per gallery. The female guards the gallery entrance and will block the entrance hole with her body as a defence against enemies. However, little has been reported about the nature and importance of natural enemies of X. mutilatus. Egg hatch begins about 7 days post oviposition and the larvae feed on the mycelia of the ambrosia fungi. Larvae are c-shaped and cream colored, without legs. Pupation occurs 2-3 weeks later, and adults emerge after about 1 week (Rabaglia, 2003;Schiefer and Bright 2004). As is typical of many ambrosia beetles, X. mutilatus has inbred polygamy. Mating occurs within the gallery immediately after eclosion. Only one to three males develop in each gallery where they remain and mate with their sisters. Males die after mating, and the females overwinter within the natal gallery (Rabaglia, 2003;Schiefer and Bright, 2004).