In this report, we describe the development of seven new polymorphic microsatellite markers for Cochliomyia hominivorax, a parasitic insect pest of primary agricultural and veterinary importance throughout the Neotropics. The number of alleles found ranged from 3 to 13 per locus, with the expected heterozygosity ranging from 0.4220 to 0.9045. The across-taxa amplification of some of these new microsatellite loci was successful in four additional Calliphoridae species. In combination with the 10 polymorphic microsatellite markers previously described, the markers developed here should provide a high resolution for assessing the fine-scale genetic structure of New World screw-worms. © 2005 Blackwell Publishing Ltd.54815817Billotte, N., Lagoda, P.J.L., Risterucci, A.M., Baurens, F.C., Microsatellite-enriched libraries: Applied methodology for the development of SSR markers in tropical crops (1999) Fruits, 54, pp. 277-288Edwards, K.J., Barker, J.H.A., Daly, A., Jones, C., Karp, A., Microsatellite libraries enriched for several microsatellite sequences in plants (1996) BioTechniques, 20, pp. 758-759(2000) Genetic Sexing and Population Genetics of Screw Worms, , August 7-11, 2000, Vienna, Austria. 19ppRaymond, M., Rousset, F., GENEPOP (version 1.2): Population genetics software for exact tests and ecumenicism (1995) Journal of Heredity, 86, pp. 248-249Rice, W.R., Analyzing tables of statistical tests (1989) Evolution, 43, pp. 223-225Rozen, S., Skaletsky, H.J., (1998) PRIMER 3, , http://www-genome.wi.mit.edu/genome_software/other/primer3.html, Code availableTorres, T.T., Brondani, R.P.V., Garcia, J.E., Azeredo-Espin, A.M.L., Isolation and characterization of microsatellite markers in the New World screw-worm Cochliomyia hominivorax (Diptera: Calliphoridae) (2004) Molecular Ecology Notes, 4, pp. 182-184Wyss, J.H., Galvin, T.J., Central America regional screw-worm eradication program (benefit/cost study) (1996) Annals of the New York Academy of Sciences, 791, pp. 241-247