FACT SHEET
Pink Bollworm
Family Gelechiidae
RECOGNITION
Diagnostic features. Usually light brown or gray with many darker scales forming spots or splotches. Forewings much longer than wide, with a fringe of hair-like scales beginning from the middle of the posterior edge of the wing, continuing around the tip, and terminating on the front edge about ¼ or 1/3 the length of the wing from the tip. The forewing terminates in a pointed tip that may be obscured by the fringe scales which may give the appearance of a flat-tipped wing. The hindwing has broad fringe about as long as the width of the wing along the hind margin and curving around to the anterior margin where it is no more than half the width of the wing in length. The distal end of the hind wing has a sigmoidal or “s-shaped” curve producing a sharp point on the anterior edge. Labial palps upturned, with two dark bands on the terminal segment of the palps. Ocelli are absent. Antennal scape has a pecten of about 5 long scales extending in a row away from the scape.
Pectinophora gossypiella (Pink Bollworm) male collected in a Delta trap. Scale bar = 1 cm.
Photo credit: Wendy Moore
Pectinophora gossypiella (Saunders)
Photo credit: Wendy Moore
Pectinophora gossypiella (pink bollworm) male genitalia, dissected and cleared. Scale bar = 1 mm. Photo credit: Wendy Moore
ECOLOGY
Life cycle. Pink bollworm eggs take about three to four days to hatch after they are laid. They are white at first and progress to an orange color as development progresses. Freshly-hatched larvae are white with a brown head. They don’t turn pink until the fourth and last larval stage. Larvae bore into the cotton plant – usually in the cotton boll – in order to feed on the seeds. The larva moves from seed to seed within the boll, chewing through the cotton fibers as it goes. Larvae take twelve to fifteen days to develop, after which they move to the soil to pupate. The brown pupa remains immobile in the top layer of the soil for seven to eight days. Adults emerge as brownish or grayish moths with dark mottling and dark spots on their wings. The females take two or three days to mate and develop eggs within her body. After this brief period she lays the majority of her eggs within ten days. Eggs are laid under the bracts of cotton bolls.
Feeding habits. Adult males and females feed on nectaries under the cotton leaves and may live for up to two months. Pink bollworm larvae burrow into cotton bolls to feed on the cotton seeds. In the process they destroy the cotton lint. This feeding damage allows other insects and fungi to enter the boll and cause additional damage.
Seasonal emergence. Pink bollworm moths overwinter as fourth instar larvae in the soil or leftover bolls from the previous season. The larvae become active and pupate when temperatures and water conditions are right and the adults emerge around late April or early May. The pink bollworm has a generation time of about one month. There may be anywhere from one to four generations in a summer. Some larvae will enter diapause in preparation for overwintering during late August and more and more larvae do this as the days become shorter and temperatures get cooler. However, it may still be possible to see adults late into the fall. Read more about pink bollworm management and life cycles here.
Photo credit: Alex Yelich
Photo credit: Alex Yelich
Photo credit: Peter Ellsworth
Photo credit: Peter Ellsworth
Pectinophora gossypiella (pink bollworm) female genitalia, dissected and cleared. Illustration from Busck 1917.