spined long-horned beetle

Spined long-horned beetle is a small to large round-necked long-horned beetle. It occurs in the United States from Massachusetts to Florida west to Wisconsin, Nebraska, and Texas, in southern Ontario Canada, and in northern Mexico. It has not been reported in Minnesota. The larvae are rarely seen. They feed under the bark of dead and dying hickory at first, then move into the heartwood. They also infest hackberry and elm, and rarely pine. Adults are found in summer in deciduous and mixed woodlands.

Adults are 5⁄16″ to ⅞″ (7.5 to 23 mm) in length and are densely covered with short, velvety hairs. They are dark brown or black with reddish-brown areas and yellow markings. The body is constricted between the thorax and the abdomen, forming a distinct rounded “neck”.

The head is reddish-brown and black. There is a narrow yellow band on the top and sides of the head behind the compound eyes. The face is slanted forward or nearly vertical, and there are two vertical yellow stripes between the eyes. The small antennae-like structures (palpi) emerging from the lower jaws (maxillae) are blunt at the tip, not pointed. The antennae are long, at least half as long as the body. Each compound eye is notched at the base of the antenna but the antenna base is not surrounded by the compound eye.

The exoskeletal plate covering the thorax (pronotum) and the hardened wing covers (elytra) are mostly black. The pronotum is rounded and widest near the middle. It is black with a large reddish-brown area on each side of the middle. A thin band of yellow hairs on the margins encircles the pronotum, broken only in the middle just behind the head. There is no yellow band across the middle.

The small plate between the bases of the elytra (scutellum) is black at the base with a broad, bright yellow margin. Each elytron has four narrow bands of yellow hairs. The first band, the one nearest the base, is bordered below by a broad reddish-brown area. The first and second bands are joined in the middle by a longitudinal stripe of white hairs. Together with a longitudinal yellow stripe on the abdomen, the first and second bands almost form a circle. The third band is a forward-pointing arc. The fourth band is almost straight across. There is a distinct spine at the tip of each elytron.

The legs are mostly yellowish-brown. On the hind leg the third segment (femur) is mostly black, yellowish-brown just at the base, and has a pair of short but distinct spines at the tip. There is a single longer spine at the tip of the fourth leg segment (tibia). The last part of each leg (tarsus), corresponding to the foot, has five segments. The fourth segment is very short and is concealed within the broadened tip of the third segment, making the tarsus appear to have only four segments.

5⁄16″ to ⅞″ (7.5 to 23 mm) in length

Deciduous and mixed woodlands

One generation per year: Summer

Adults are attracted to light at night.

Larvae feed under the bark of dead and dying hickory at first, then move into the heartwood. They also infest hackberry and elm, and rarely pine.

Sources

29, 30, 82, 83.

Not reported in Minnesota

Location: Slinger, Wisconsin