The Mediterranean fruit fly, 

commonly called medfly, or 

Moscamed in Spanish, is one 

of the world’s most destructive 

agricultural pests, threatening 

more than 300 kinds of fruits, 

nuts, and vegetables. The female 

medfly attacks ripening fruit, 

piercing the soft skin and laying 

eggs in the pulp. The eggs hatch 

into larvae, or maggots, that feed 

inside the fruit pulp. This causes 

the fruit to rot. 

Distribution

The medfly is found in most 

tropical and subtropical areas 

of the world. Originating in 

Africa, the pest has since spread 

throughout the Mediterranean 

region, southern Europe, the 

Middle East, Western Australia, 

South and Central America, and 

Hawaii. Most recently, it was also 

detected in the Caribbean. 

In general, the medfly’s 

presence in the United States 

has been limited. The only State 

with an established medfly 

population is Hawaii, where it 

has been present since 1910. No 

eradication program is underway 

in Hawaii. On the U.S. mainland, 

Animal and Plant Health Inspection Service

Plant Protection and Quarantine

Mediterranean Fruit Fly (Ceratitis capitata)

the first infestations occurred 

in Florida in 1929. Several 

infestations have been found 

and eradicated on the mainland 

since then. These efforts have 

kept the medfly from becoming 

established in the mainland 

United States. 

In 2015, the medfly was 

discovered in Punta Cana, 

Dominican Republic, and 

Cabo Rojo in Puerto Rico. The 

Caribbean had previously been 

free of this pest. In 2014, the 

medfly was also detected in 

Riverside County, CA. These 

detections are now being 

eradicated.

Damage

In the United States, the medfly 

could attack apples, apricots, 

avocados, citrus, cherries, figs, 

grapes, guavas, kumquats, 

loquats, mangoes, nectarines, 

papayas, peaches, pears, 

peppers, persimmons, plums, 

tomatoes, and several types of 

nuts, among many other crops. 

The damage medflies cause 

makes the product unfit for sale 

to consumers.

If the medfly were to become 

established in our country, 

consumer prices would go up 

and produce would become 

less available. Also, pesticide 

use would increase in backyard 

gardens and commercial farms. 

Other impacts would include 

damage to the economy from 

export sanctions, lost markets, 

treatment costs, reduced crop 

yields, and premature fruit drop.

Appearance and 

Life Cycle

The adult medfly is slightly 

smaller than a common housefly 

and is very colorful. It has dark 

blue eyes; a shiny, black thorax 

(back); and a yellowish abdomen 

with silvery crossbands. Its 

wings, normally drooping, 

display a blotchy pattern with 

yellow, brown, and black spots 

and bands.

The life cycle of the medfly has 

five phases:

1) The adult female deposits 

eggs under the fruit’s skin.

2) The eggs hatch and produce 

wormlike larvae (maggots).

Pest Alert

Medfly adult (USDA ARS, Scott Bauer) Medfly adult (USDA APHIS) Medflies can be produced in the laboratory by 

bathing their eggs in warm water—a process 

that kills the female embryos but doesn’t 

harm the male embryos. In the pupal stage, 

the males can be irradiated to render them 

sexually sterile. (USDA ARS, Scott Bauer)
Be on the lookout for the 

medfly, and support control and 

eradication efforts in your area.

USDA is an equal opportunity provider 

and employer.

APHIS 81-35-029

Issued June 2015

3) The larvae feed on the fruit’s 

pulp before dropping to the 

ground, where the larvae

burrow into the soil.

4) The larvae transform into

pupae in the soil.

5) The pupae mature into 

adults (flies) and emerge 

from the soil.

Under tropical summer weather 

conditions, the medfly completes 

its life cycle in 21 to 30 days.

Preventing Medfly 

Spread

If we find an infestation in 

the United States, the U.S. 

Department of Agriculture 

(USDA) and the States impose 

quarantine regulations to help 

keep the pest from spreading 

through the movement of 

infested fruit—via trade 

shipments or by people 

unknowingly carrying infested 

fruit from one place to another. 

Federal quarantine laws regulate 

the interstate movement of any 

products that may harbor the 

fly. State regulations control the 

movement of these products 

going to uninfested areas within 

a State. 

Regulated items include all 

medfly-host fruits and vegetables 

present in the quarantine area. 

Open-air fruit and vegetable 

stand owners, mobile vendors, 

and other fruit handlers must 

sign compliance agreements with 

the medfly eradication program 

to conduct business. Under 

these agreements, handlers must 

take basic steps to protect host 

material from pest infestation 

and sell only approved fruits and 

vegetables. Commercial and 

homegrown produce may not 

be moved without inspection, 

treatment, and certification by 

program officials. 

What You Can Do

We need your help to keep the 

medfly from spreading. Please 

cooperate with agricultural 

workers who may be in your 

area surveying for the pest 

and applying treatments to 

eradicate it. Know and follow 

any quarantine restrictions in 

medfly-infested areas. Also, 

when traveling, declare all food, 

live animals, and plant or animal 

products to a U.S. Customs 

and Border Protection officer or 

agriculture specialist at the first 

port of entry. 

Learn More

For more information about 

medfly, go to www.aphis.usda.

gov/plant-health/medfly or 

visit www.HungryPests.com. 

You may also call your nearest 

USDA Animal and Plant Health 

Inspection Service (APHIS) 

office. A list of contacts is on our 

Web site at www.aphis.usda.gov/

planthealth/sphd.

Medfly larvae consuming a highly nutritious, Medfly trap (USDA APHIS)

corn-based diet (USDA ARS, Scott Bauer)

Medfly larva (USDA APHIS)