FIRST RECORDS OF ZAPRIONUS INDIANUS (DIPTERA: DROSOPHILIDAE), A PEST SPECIES ON COMMERCIAL FRUITS FROM PANAMA AND THE UNITED STATES OF AMERICA

Zaprionus indianus Gupta 1970 (Diptera: Drosophilidae) is native to Africa, the Middle East, and southern Eurasia (Chassagnard & Kraaijeveld 1991; Baichli 1999-2005). It was first found in the Americas in 1999, when it was reported from Sao Paulo, Brazil (Vilela 1999). Since then, it has spread rapidly through Brazil (Santos et al. 2003; Tidon et al. 2003; Ledo & Tidon 2004; da Silva et al. 2005) and Uruguay (Goni et al. 2001, 2002) and has been predicted to reach the USA in the near future (David et al. 2006). Here we report the first records of Z. indianus from Panama and the USA. On 6 and 7 Oct 2003, DH collected several individuals of Z. indianus on Isla Contadora, Panama. KH reared several individuals of Zaprionus (Steck 2005) from fruits of longan, Dimocarpus longan Lour., and Barbados cherry, Malpighia emarginata Sess6 & Moc. ex DC., collected on 26 Jul 2005 in St. Lucie Co., Florida. Dr. C. Ribeiro Vilela confirmed the identification as Z. indianus.


Zaprionus indianus
is native to Africa, the Middle East, and southern Eurasia (Chassagnard & Kraaijeveld 1991;Bächli 1999Bächli -2005. It was first found in the Americas in 1999, when it was reported from São Paulo, Brazil (Vilela 1999). Since then, it has spread rapidly through Brazil (Santos et al. 2003;Tidon et al. 2003;Leão & Tidon 2004;da Silva et al. 2005) and Uruguay (Goní et al. 2001(Goní et al. , 2002 and has been predicted to reach the USA in the near future (David et al. 2006). Here we report the first records of Z. indianus from Panama and the USA.
On 6 and 7 Oct 2003, DH collected several individuals of Z. indianus on Isla Contadora, Panama. KH reared several individuals of Zaprionus (Steck 2005) (Chassagnard 1988;Chassagnard & Tsacas 1993) and by direct comparison with alcohol-preserved material from a laboratory stock of Z. indianus provided by Dr. Jean David. Zaprionus indianus is yellowish overall and has an even number of distinctive silvery-white stripes on the top of the head and the thorax and a series of 4 to 6 distinct composite spines on the anterior femora. These spines are not located on small tubercles, and each has a second short branch at its base, functioning as a rest for the tibia of the folded leg. The narrow (relative to those of other species) black bands bordering the silvery thoracic stripes do not widen on the scutellum, and the scutellum is without a white tip (see van der Linde 2006 for more details). This combination of characters is sufficient to distinguish Z. indianus from all other known species of the genus.
This species has been recorded as a pest on oranges, peaches, and figs in Brazil (Santos et al. 2003) and might therefore become a pest in the USA. A pest alert has been issued by the Division of Plant Industry, Florida Department of Agriculture & Consumer Services (Steck 2005). The species will be difficult to control because its breeding substrates are not limited to cultivated fruits (Santos et al. 2003;Steck 2005) and because of its ability to lay eggs on fruits that are still on the plant Tidon et al. 2003;Steck 2005). In Florida, we reared Z. indianus from ripe M. emarginata , P. granatum , E. japonica , and D. longan fruits that were collected directly from the tree. In most host species, fruit damage is necessary to allow Z. indianus access to fruit on the tree. An important exception is figs, where the eggs are laid at the ostiole, which gives easy and direct access to the soft contents of the fruits (Vilela et al. 2001;. Infested figs are unsuitable for human consumption. As a result, fig production has been reduced by 40-50% in some areas (Stein et al. 2003) and exports by up to 80% (Stein et al. 2003). Closing the ostiole with adhesive (producer) tags, gel, or Bordeaux mixture reduced the infestation with Z. indianus dramatically .
Catching a species in the act of arriving offers a rare opportunity to study the dynamics of such an invasion in progress. We are confident that these are recent introductions for both countries, as we did not find this species in previous collections in the same areas. Individuals of this species collected in Tallahassee will be deposited at the American Museum of Natural History. Other Florida specimens are deposited in the Florida State Collection of Arthropods in Gainesville.

S UMMARY
Zaprionus indianus has continued its range expansion in the Western Hemisphere. We report here the first observations from Panama (2003) and Florida, USA (2005). We are confident that the invasions were discovered in progress in both places. This species is a generalist that uses both cultivated and native fruits as breeding substrates. It has been reported as a pest species on figs in Brazil but generally breeds only on fallen fruits or on damaged fruits still on the tree.