1167 Accepted by P. Adler: 27 Feb. 2006; published: 6 Apr. 2006 47 ZOOTAXA ISSN 1175-5326 (print edition) ISSN 1175-5334 (online edition) Copyright © 2006 Magnolia Press Zootaxa 1167: 47–60 (2006) www.mapress.com/zootaxa/ Simulium (Inaequalium) margaritatum, a new species of black fly (Diptera: Simuliidae) from the central region of Bahia State, Brazil MATEUS PEPINELLI 1 , NEUSA HAMADA 2 & SÉRGIO LUIZ BESSA LUZ 3 1 Laboratório de Entomologia Aquática, Departamento de Hidrobiologia, Universidade Federal de São Car- los, Caixa Postal 676, 13565-905, São Carlos, SP, Brazil. E-mail: mateuspepi@yahoo.com.br 2 Coordenação de Pesquisas em Entomologia, Instituto Nacional de Pesquisas da Amazônia, Caixa Postal 478, 69011-970, Manaus, AM, Brazil. E-mail: nhamada@inpa.gov.br 3 Centro de Pesquisa Leônidas e Maria Deane - Biodiversidade em Saúde, Fundação Oswaldo Cruz, Rua Tere- sina n. 476, Adrianópolis, 69057-070, Manaus, AM, Brazil. E-mail: sergioluz@amazonia.fiocruz.br Abstract A new species of black fly, Simulium (Inaequalium) margaritatum, is described based on the male, female, pupa, and larva. This new species was collected in small streams in the Chapada Diamantina National Park and surrounding area in the state of Bahia, Brazil. Key words: aquatic insects, black flies, Inaequalium, Neotropical Region, taxonomy, Parque Nacional Chapada Diamantina Introduction Simulium (Inaequalium) Coscarón & Wygodzinsky is a subgenus of black flies that includes 19 species, 17 of which occur in Brazil (Crosskey & Howard 2004; Pessoa et al. 2005). There are two species groups (inaequale and botulibranchium); thirteen species are included in the first group and three in the second; one species, Simulium lurybayae Smart, was not included in either of these groups (Coscarón 1987, 1991; Coscarón & Coscarón- Arias 1997). Strieder & Py-Daniel (2002) corroborated these two species groups but placed Simulium travassosi D’Andretta & D’Andretta, formerly in the inaequale species group, in the botulibranchium group. However, Crosskey & Howard (2004) maintained S. travassosi in the inaequale species group, listed S. lurybayae in the botulibranchium species group, and did not include Simulium pseudoexiguum Nunes de Mello & Barbosa de Almeida in any species group. Recently, a new species was described from the state of