Intraspecific Variation of Second Internal Transcribed Spacer of Nuclear Ribosomal DNA Among Populations of Anopheles (Kerteszia) cruzii (Diptera: Culicidae)

Anopheline species of the subgenus Kerteszia, including Anopheles (Kerteszia) cruzii Dyar & Knab (Diptera: Culicidae), are bromeliad-malaria vectors in the Atlantic rain forest of Brazil. Morphological, genetic, and molecular polymorphisms among different populations of An. cruzii have been reported, and it has been suggested that this taxon includes a complex of cryptic species. Specimens of An. cruzii were collected in the states of São Paulo and Santa Catarina, from locations where autochthonous malaria cases have been reported during the last decade. The second internal transcribed spacers (ITS2) of nuclear ribosomal DNA of the captured specimens were sequenced and compared with each other. Intraspecific ITS2 sequence polymorphisms were identified, and nucleotide divergence among specimens varied from 0.3 to 0.9%. The number of nucleotides in the ITS2 sequences of these mosquitoes varied from 327 to 334, and the CG contents varied from 61.7 to 62%. The data provide further indication of An. cruzii being a complex of cryptic species.