Squash Vine Borer
Head: Top of head dark bronze-black. Eyes orange. Nose cone (palpi) orange, white on underside.
Antenna: Black. Males have row of hairs on one side (pectinate), antenna appear thicker.
Thorax: Dark bronze-black with white tuft a side edges.
Wings: Forewing bronze-black; fringe thick sometimes slightly lighter in colour. Hindwing transparent, veins and fringe brown.
Legs: Black with orange and black scaling. Hind legs thickly covered with orange and black hair. Front foot black, mid and hind feet striped.
Abdomen: Colour can vary from yellow to orange. Segments 1 and 2 black. Segment 3 orange. Other segments mostly orange with a large black dot at center of segment. Male abdomen usually has last 2 segments dark, with pointed hair tuft. Female tip bluntly rounded, usually red. Underside orange-yellow.
Size: 14 to 16 mm long. Wingspan 25 to 32 mm.
Habitat: Gardens and meadows.
Food: Adults often found on milkweed blossoms and flowering garden herbs. Larvae feed on squashes, pumpkin, zucchini, gourds. Sometimes on cucumber and watermelon.
Flight Time: Late June to August.
Life Cycle: Reddish-brown, somewhat flattened, very tiny eggs laid on crown root to 1 foot above on stems, on leaf stalks, leaves and fruit buds. Larva bores into plant stems and feed on juices, leaving a sawdust trail. Mature larvae burrow 25 to 50 mm into the soil and over-winter, pupating in the spring in the same tunnel. Larvae appear grub-like, but with legs – 3 pair on thorax and 5 pair on abdomen. Mature larvae are 25 mm long, white with a dark head. Adults are day flyers. One generation per year in Ontario.
Comments: Essex County – Ojibway Prairies; Pelee Island. Common in Ontario.
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