RESEARCH ARTICLE Genetic diversity of Parides ascanius (Lepidoptera: Papilionidae: Troidini): implications for the conservation of Brazil’s most iconic endangered invertebrate species N. Seraphim 1,7 • M. A. Barreto 2 • G. S. S. Almeida 3 • A. P. Esperanc ¸o 4 • R. F. Monteiro 4 • A. P. Souza 2,5 • A. V. L. Freitas 1 • K. L. Silva-Branda ˜o 6 Received: 8 July 2015 / Accepted: 7 December 2015 Ó Springer Science+Business Media Dordrecht 2015 Abstract Parides ascanius (Lepidoptera: Papilionidae) is a butterfly endemic to the sand forests (‘‘restingas’’) of one of the most populated areas of Brazil (from Rio de Janeiro state to South Espı ´rito Santo state), and was the first invertebrate officially recognized as being threatened in Brazil. Here we present a panel of eight polymorphic microsatellite loci and partial sequences of mitochondrial gene COI aiming to characterize this butterfly’s genetic diversity and understand its distribution among the extant populations. We estimate F ST metrics, migration rates, cluster assignment, and spatial structure of genetic diver- sity. F ST and statistics indicate low genetic structure and no evidence for endogamy, with all populations connected by high migration rates. Seven populations have low perma- nence rates (68–75 %) with increased migration probabilities for all populations. One population displays higher permanence rate (87.7 %), as the metropolitan matrix isolates it. Spatial analysis shows a global structure around the city of Rio de Janeiro and the Guanabara Bay; assignment analysis recovers six clusters evenly spread among sampled populations. These findings are consistent with a natural scenario of metapopulation dynamics for P. ascanius, with low genetic diversity and no endogamy, but progressively isolated by the metropolitan matrix. Con- servation efforts should focus in connecting the isolated population, broaden the searches for new populations, and preserve all extant habitat patches where P. ascanius still occurs. Keywords Metapopulation Á Butterfly Á Microsatellites Á Restinga Á Brazilian sand forests Á Atlantic rainforest Á Invertebrate conservation Electronic supplementary material The online version of this article (doi:10.1007/s10592-015-0802-5) contains supplementary material, which is available to authorized users. & N. Seraphim noemyseraphim@gmail.com 1 Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Cidade Universita ´ria Zeferino Vaz, Caixa postal 6109, Bara ˜o Geraldo, Campinas, SP 13083-970, Brazil 2 Centro de Biologia Molecular e Engenharia Gene ´tica, Universidade Estadual de Campinas (UNICAMP), Cidade Universita ´ria Zeferino Vaz, Bara ˜o Geraldo, Campinas, SP 13083-875, Brazil 3 Departamento de Biologia Geral, Instituto de Biologia, Universidade Federal Fluminense, Caixa Postal 100.436, CEP: 24020-971, Nitero ´i, RJ CEP 24020-150, Brazil 4 Laborato ´rio de Ecologia de Insetos, Departamento Ecologia, Instituto de Biologia, Universidade Federal do Rio de Janeiro, CP68020, Rio de Janeiro, RJ CEP 21941-590, Brazil 5 Departamento de Biologia Vegetal, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Cidade Universita ´ria Zeferino Vaz, Caixa postal 6109, Bara ˜o Geraldo, Campinas, SP 13083-970, Brazil 6 Laborato ´rio de Melhoramento de Plantas, Centro de Energia Nuclear na Agricultura, Universidade de Sa ˜o Paulo, Campus ‘‘Luiz de Queiroz’’. Av. Centena ´rio, 303, Piracicaba, SP 13400-970, Brazil 7 Present Address: Institudo Federal de Educac ¸a ˜o, Cie ˆncia e Tecnologia de Sa ˜o Paulo, Campus Capivari, Avenida Dr E ˆ nio Pires de Camargo, 2971, Capivari, SP CEP 13360-000, Brazil 123 Conserv Genet DOI 10.1007/s10592-015-0802-5