Image Credit: Image copyright www.InsectIdentification.org; No Reproduction Permitted
The Squash Vine Borer is a moth that mimics stinging bees and is harmless to people, but its offspring are efficient damage dealers.
The Squash Vine Borer moth is harmless to squash, zucchini, pumpkin, and melon plants, but its larvae are destructive. Females lay fertilized eggs that look like small, brown footballs on the plant. Once larvae hatch, they bore into the stem of the plant and begin eating the pith inside it. They look like white wormy grubs with brown heads. Look for entry holes and frass at the base of a stem. Wilting leaves is a sign of infiltration, followed by rotting stems and eventually the entire plant if left unchecked. Nymphs are grayish-white and resemble aphids. They move in groups and can be found under leaves and along the stem.
Preventing adults from laying eggs in the first place is the best measure of defense against this insect. The red and black adult moth is conspicuous and easy to see. Moth traps may help eliminate them before they reproduce. Using row covers for a few weeks also prevents them from laying eggs on the host plant. Planting a second round of squash after the adults have reproduced will ensure a later harvest. If a stem is found to be infected (wilting leaves, pinholes and frass at the base), cut it off the plant. Cut down the length of the stem and a look inside to confirm the presence of the larval worm.
Scientific Name: Melittia cucurbitae
Butterfly or Moth
Size (Adult; Length): 28mm to 32mm (1.09in to 1.25in)
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.
Butterfly and Moth Anatomy
Antennae: Butterflies and Moths have a pair of antennae on the head used as sensors.
Head: The head is home to the insect's eyes, antennae, and proboscis.
Thorax: Home to the three pairs of legs as well as vital internal organs.
Abdomen: Contains vital internal organs such as the heart(s) and reproduction facilities.
Forewing: The upper, forward wing pair used for flying.
Hindwing: The lower, rearward wing pair used for flying.
NOTE: Butterflies and Moths are part of the Lepidopteran order as they share many similarities.