The larva, pupa, male and female of Simulium daltanhani n. sp.
are described and illustrated. This species shares diagnostic
characteristics with Simulium quadrifidum Lutz, Simulium
cauchense Floch & Abonnenc, Simulium brevifurcatum Lutz and
Simulium siolii Py-Daniel. It was collected in three counties
(Manaus, Presidente Figueiredo and Itacoatiara) in the State of Amazonas,
Brazil. Its habitat includes streams in disturbed, open areas where the
forest has been cut for road construction; it was not collected in adjacent
forested streams, suggesting that it colonizes disturbed habitats. The
larval subesophageal ganglion is discussed as a useful character, when
pigmented, to distinguish this species within a limited geographic
area.
