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EENY-021
Papaya Fruit Fly (suggested common name),
Toxotrypana curvicauda Gerstaecker (Insecta: Diptera:
Tephritidae)1
H. L. Selman, J. B. Heppner, and T. R. Fasulo2
1. This document is EENY-021, one of a series of the Department of Entomology and Nematology, UF/IFAS Extension. Original publication date March
2001. Revised April 2015. Reviewed April 2018. Visit the EDIS website at http://edis.ifas.u.edu. This document is also available on the Featured
Creatures website at http://entnemdept.ifas.u.edu/creatures/.
2. H. L. Selman; J. B. Heppner (retired); and T. R. Fasulo (retired), Department of Entomology and Nematology; UF/IFAS Extension, Gainesville, FL 32611.
The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and other services only to
individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex, sexual orientation, marital status, national
origin, political opinions or aliations. For more information on obtaining other UF/IFAS Extension publications, contact your county’s UF/IFAS Extension oce.
U.S. Department of Agriculture, UF/IFAS Extension Service, University of Florida, IFAS, Florida A & M University Cooperative Extension Program, and Boards of County
Commissioners Cooperating. Nick T. Place, dean for UF/IFAS Extension.
Introduction
e papaya fruit y, Toxotrypana curvicauda Gerstaecker,
is the principal insect pest of papaya (Carica papaya L.)
throughout the tropical and subtropical areas of the New
World. e insect was introduced into Florida in 1905,
most likely from the West Indies on papaya shipments. It
rst became established in the Florida Keys and Miami,
then spread throughout the state wherever papayas are
grown. Papaya fruit y larvae and adults have been found
in Florida in every month of the year. Although originally
considered to be monophagous, infesting only wild and
cultivated papaya, the insect has also been reported on
mango and milkweed in Florida, and other plant species in
Mexico.
Synonymy
Mikimyia furcifera Bigot.
Distribution
e papaya fruit y is distributed throughout the Carib-
bean, particularly in Puerto Rico, the Dominican Republic,
Trinidad, Cuba, and the Bahamas. It is also found in
Central America (Belize, Costa Rica, Guatemala, Hon-
duras, Mexico, Panama) and South America (Columbia,
Venezuela). In the United States, the y is found in south-
ern Texas and southern Florida.
Description
Adult
Commonly mistaken for a vespid wasp due to its size, form,
coloration, and behavior, the papaya fruit y is predomi-
nantly yellow marked with black. e female has a very
long, slender abdomen with a greatly elongated, curved
ovipositor which exceeds the length of its body (body
length: 8.5–12.5 mm; ovipositor length: 9–14 mm). e
Figure 1. Adult female papaya fruit y,
Toxotrypana curvicauda
Gerstaecker.
Credits: Doug Caldwell, UF/IFAS
2
Papaya Fruit Fly (suggested common name), Toxotrypana curvicauda Gerstaecker (Insecta: Diptera: Tephritidae)
male y resembles the female with a hairy, but less mark-
edly banded, stalked abdomen and without the ovipositor
(body length: 11–13.5 mm; wing width: 8.5–11 mm).
Egg
e egg is long, slender, and yellow with a long cylindrical
stalk. e average length is approximately 2.5 mm, and the
largest diameter is 0.2 mm.
Larva
Larvae are white and the typical fruit y shape (cylindrical-
maggot-shape, elongate, with the anterior end narrowed
and somewhat recurved ventrally, with anterior mouth
hooks, ventral fusiform areas and attened caudal end). e
last instar is large compared to other species at 13–15 mm
in length. Other features include the venter with fusiform
areas on segments 4 through 11, anterior buccal carinae
narrow, long and usually 13 to 15 in number, anterior
spiracles nearly straight on dorsal edge but with noticeable
depression centrally, with tubules numerous, varying from
22 to 28 and usually with some tubules in a somewhat
secondary dorsal row.
e primary diagnostic characters for papaya fruit y larvae
involve the large anterior spiracles, the number of narrow
buccal carinae (13 to 15), the lack of prominent tubercles
on the caudal end of the larva, and a bid anal elevation.
e anterior spiracles are longer than in most other known
fruit y larvae. e caudal end of the body is particularly
distinctive in lacking any prominent tubercles or papillules
and has only the spiracular region as a depressed plate, but
some indistinct and small tubercles and papillules are pres-
ent. However, relative to other tephritid larvae the species
Figure 2. Florida distribution of the papaya fruit y,
Toxotrypana
curvicauda
Gerstaecker, in 2014.
Credits: G. J. Steck and B. D. Sutton, Division of Plant Industry
Figure 3. Adult female papaya fruit y,
Toxotrypana curvicauda
Gerstaecker.
Credits: Division of Plant Industry
Figure 4. Adult male papaya fruit ies,
Toxotrypana curvicauda
Gerstaecker, dorsal view (lower left) and ventral view (upper right).
Credits: James L. Nation, UF/IFAS
3
Papaya Fruit Fly (suggested common name), Toxotrypana curvicauda Gerstaecker (Insecta: Diptera: Tephritidae)
has the appearance of a smooth caudal end. e pharyngeal
skeleton is particularly distinctive due to the sclerotization
along the dorsal margin of the pharyngeal plate.
Cephalo-pharyngeal skeleton with large convex mouth
hook (approx. 2X hypostome length), having a large
bulbous lower muscle attachment; hypostomium long, with
bulbous subhypostomium; post-hypostomial plates curved
dorsally to dorsal bridge sclerotizations; parastomium
prominent, pointed; anterior of dorsal bridge with a slightly
sclerotized point, more extensive internally towards dorsal
wing plate; pharyngeal plate somewhat shorter than dorsal
wing plate, both with relatively extensive sclerotizations,
especially distinctive along the mid-dorsal margin of the
pharyngeal plate beneath median hood.
e sclerotizations of the cephalo-pharyngeal skeleton
vary to some extent (see Figure 35 in Phillips 1946), but
the prominent sclerotization of the dorsal margin of the
pharyngeal plate, the strong central sclerotizations and
the large mouth hooks are distinctive for the species. e
anterior spiracles usually have a large number of tubules
when there is an apparent secondary row of tubules.
Illustrations and descriptions of the caudal end of the
larva of this species have been incorrect in past works
(Berg 1979, Phillips 1946) in not noting the small D1-2
and triangle of L1-3 papillules. Compared to other fruit
y larvae these papillules, as well as the small tubercle for
papillule V1, are not readily evident; thus, the larvae appear
to have a nondescript smooth caudal end. Careful examina-
tion, however, reveals the papillules, tubercles and raised
plates as illustrated herein. Published keys to larvae (e.g.,
Berg 1979) are not compromised, however, since routine
identication eorts will not generally make note of the
small papillules and tubercles. Larvae examined came from
veried samples from Florida in the larval collection of the
Florida State Collection of Arthropods.
Caudal end lacking any prominent tubercles or papillules
but with several small papillules; the caudal end generally
convex, with depressed subquadratic spiracular plate; all
papillules not easily seen, with paired dorsal papillules
(D1 and D2) angled dorsally, an obtuse triangle of three
intermediate papillules (I1-3) ventral to spiracular plate,
and a single small V1; all tubercles or raised plates very
slightly elevated to maintain an overall impression of a
Figure 5. Larvae of the papaya fruit y,
Toxotrypana curvicauda
Gerstaecker, in papaya.
Credits: Scott Bauer, USDA
Figure 6. Head and buccal carinae (lateral view) of the larva of the
papaya fruit y,
Toxotrypana curvicauda Gerstaecker.
Credits: Division of Plant Industry
Figure 7. Anterior spiracles of the papaya fruit y larva.
Figure 8. Cephalo-pharyngeal skeleton (left side) of the larva of the
papaya fruit y,
Toxotrypana curvicauda Gerstaecker.
Credits: Division of Plant Industry
4
Papaya Fruit Fly (suggested common name), Toxotrypana curvicauda Gerstaecker (Insecta: Diptera: Tephritidae)
relatively smooth caudal end; L1 papillule not evident;
I1 somewhat more prominent than all other papillules;
posterior spiracles elongate (approx. 4X to 5X width), with
central spiracles nearly straight, dorsal pair slightly angled,
and ventral pair angled ventrally; interspiracular processes
(hairs) in small tus with needle-like extensions; spiracular
wall thick and internal bars prominent; anal elevation with
lobes bid, rounded.
Pupa
e puparia are stout and cylindrical with rounded ends
and vary in length from 8.5–12 mm. ey are yellow to
almost black. e color does not indicate age, as some
remain light colored until the adults emerge.
Life Cycle
e female is capable of producing 100 or more eggs. e
female fruit y oviposits in the green immature fruit by
thrusting her ovipositor through the esh of the fruit. She
then deposits a group of 10 or more long, slender eggs in
the papaya’s central cavity where the young larvae feed on
developing seeds and the interior parts of the fruit. As the
larvae mature, they eat their way out of the fruit, drop to
the ground beneath the plant, and pupate just below the soil
surface. Flies emerge in about two to six weeks, depending
upon humidity and temperature of the soil. Eggs are usually
laid in small fruit, about two to three inches in diameter,
but they may be deposited in smaller or larger fruit. How-
ever, unripe papaya juice is fatal to the larvae so the fruit
must be ripe before the larvae begin to eat their way out
of the inner cavity. Eggs hatch approximately 12 days aer
oviposition and larval development in the fruit lasts about
15 to 16 days.
Damage
Fruit infected with papaya fruit y larvae will turn yellow
and drop from the tree prematurely. Damage levels in
Florida uctuate between 2 and 30% of fruits infested
during the spring-summer season.
Figure 9. Caudal end of the larva of the papaya fruit y,
Toxotrypana
curvicauda
Gerstaecker.
Credits: Division of Plant Industry
Figure 10. Posterior spiracles (left side) of the papaya fruit y larva.
Credits: Division of Plant Industry
Figure 11. Anal lobes of the papaya fruit y larva.
Credits: Division of Plant Industry
5
Papaya Fruit Fly (suggested common name), Toxotrypana curvicauda Gerstaecker (Insecta: Diptera: Tephritidae)
Management
Prevention of egg-laying is the key to controlling papaya
fruit y. It is necessary to kill the adult female before she
deposits eggs in the fruit.
Florida Crop/Pest Management Prole: Papaya, http://edis.
ifas.u.edu/pi053
Bagging can be an eective control measure for the fruit
y in small plantings (one to 25 plants or less than 1/10
hectare). Bagging should begin when the fruit is small,
shortly aer the owers have fallen o. Each fruit should
be enclosed in a paper bag or rolled tube of newspaper and
tied around the stem. is method can be very practical
and successful if enough labor is available. Attention to
covering new fruit and increasing the covering as the fruits
increase in size is necessary.
Sanitation is also important in the control of the papaya
fruit y. All dropped and prematurely ripe fruit, as well as
infested young fruit, must be destroyed in order to prevent
the larvae from developing into adults.
Very little research has been done on the biological control
of papaya fruit y, considering its economic importance.
One parasitic wasp in particular, Doryctobracon toxotrypa-
nae Marsh (Hymenoptera: Braconidae), from southern
Mexico and Costa Rica, may have potential for control.
Pheromone lures and traps are critical for monitoring fruit
y populations, measuring distribution, and acquiring
control or eradication. Research in Miami and Gainesville,
Florida, has resulted in the development of a pheromone
lure and functional trap for this species. Studies are pres-
ently being performed to test female pheromone lures with
the addition of host odor chemicals in order to increase
the attraction of ies and to improve its performance in
competition with males.
Other possible control measures have been suggested for
future research, such as papaya fruit without seeds. Due
to the strong dependence of larval feeding on the seeds as
an early food source, a seedless papaya variety could be
explored. For similar reasons, thicker pulp could possibly
provide enough resistance to hinder the ovipositor from
successfully depositing eggs. Another suggestion has been
to look for varieties of papaya with higher levels of chemi-
cals that are toxic to the larvae.
Selected References
Benjamin FH. 1934. Descriptions of some native trypetid
ies with notes on their habits. U.S. Department of Agricul-
ture Technical Bulletin 401: 1–95.
Berg GH. 1979. Pictorial key to fruit y larvae of the
family Tephritidae. San Salvador: Organ. Internac. Region.
Sanidad Agropec. 36 pp.
Castrejon-Ayala F, Camino-Lavin M. 1991. New host plant
record for Toxotrypana curvicauda (Diptera: Tephritidae).
Florida Entomologist 74: 466.
Greene CT. 1929. Characters of the larvae and pupae of
certain fruit ies. Journal of Agricultural Research 38:
489–504.
Heppner JB. (1986. Larvae of Fruit Flies III. Toxo t ry pan a
curvicauda (papaya fruit y) (Diptera: Tephritidae). http://
www.freshfromorida.com/pi/enpp/ento/entcirc/ent282.
pdf (11 March 2015).
Ibrahim RB. 1980. Fruit Flies of Florida (Diptera:
Tephritidae). Ph. D. Dissertation: University of Florida.
Toxotrypana curvicauda Gerstaecker. p. 188–190.
Knab F, Yothers WW. 1914. Papaya fruit y. Journal of
Agricultural Research 2: 447–453.
Landolt PJ. 1994. Fruit of Morrenia odorata (Asclepia-
daceae) as a host for the papaya fruit y, Tox o tr y pan a
curvicauda (Diptera: Tephritidae). Florida Entomologist
77:287-288.
Landolt PJ. 1990. Behavior of the papaya fruit y (Diptera:
Tephritidae): host nding and oviposition. Environmental
Entomology 19: 1305–1310.
Landolt PJ. 1984. Behavior of the papaya fruit y, Tox o-
trypana curvicauda Gerstaecker, (Diptera: Tephritidae).
Folia Entomologica Mexicana 61: 215–224.
Landolt PJ, Heath RR. 1996. Development of phermone-
based trapping systems for monitoring and controlling
tephritid fruit ies in Florida. pp. 197–207. In Rosen D,
Bennett FD, Capinera JL. (editors). Pest Management in the
Subtropics. Intercept Limited, United Kingdom.
Mason AC. 1922. Biology of the papaya fruit y, Toxo t ry pa-
na curvicauda, in Florida. U.S. Department of Agriculture
Technical Bulletin 1081. 10 pp.
6
Papaya Fruit Fly (suggested common name), Toxotrypana curvicauda Gerstaecker (Insecta: Diptera: Tephritidae)
Norrbom AL. (31 October 2001). Toxotrypana curvicauda
Gerstaecker. e Diptera site. http://www.sel.barc.usda.gov/
diptera/tephriti/Toxotryp/curvic.htm (11 March 2015)Peña
JE. 1988. Eectiveness of pesticides against two tropical
fruit pests. Proceedings of the Florida State Horticultural
Society 101: 249–251.
Peña JE, Howard DF, Litz RE. 1986. Feeding behavior of
Toxotrypana curvicauda (Diptera: Tephritidae) on young
papaya seeds. Florida Entomologist 69: 427–428.
Peña JE, Johnson FA. (August 2006). Insect management in
papaya. EDIS. (no longer available online).
Phillips VT. 1946. e biology and identication of trypetid
larvae (Diptera: Trypetidae). Memoirs of the American
Entomological Society 12: 1–161.
Weems Jr. HW. (July 1969).. Papaya fruit y (Tox otr y pan a
curvicauda Gerstaecker), 1860 (Diptera: Tephritidae).
FDACS - Division of Plant Industry. http://www.freshfrom-
orida.com/pi/enpp/ento/entcirc/ent086.pdf (11 March
2015).
White IM, Elson-Harris MM. 1994. Fruit Flies of Economic
Signicance: eir Identication and Bionomics. CAB
International. Oxon, UK. 601 pp.
Wolfenbarger DO, Walker SD. 1974. Two major pest
problems of papayas. Proceedings of the Florida State
Horticultural Society 87: 384–385.
