Genetic evidence for the existence of cryptic species in theAnopheles albitarsis complex in Brazil: Allozymes and mitochondrial DNA restriction fragment length polymorphisms

Abstract

Allozyme and mitochondrial DNA (mtDNA) restriction studies were undertaken to determine the extent of genetic divergence among field populations of Anopheles albitarsis in Brazil. Two sympatric species, An. deaneorum and An. marajoara, were identified in collections from Costa Marques (CM), Rondonia. Genetic evidence includes (1) the presence of two types of individuals, each with diagnostic allelic clusters (for Had-1, Pgi-1, Pep-1, Mpi-1, and Idh-1), (2) a deficiency of heterozygotes, and (3) characteristic mtDNA haplotypes. In addition, two allopatric cryptic species of An. marajoara were identified, one from Iguape (An. marajoara form IG), Sao Paulo state, and the other from the Island of Marajo (An. marajoara form MA). Though form IG and form-MA resemble form CM in wing spot morphology, they differ from it in diagnostic allozymes and mtDNA haplotypes. An. marajoara form CM had a higher variability (mean heterozygosity, H = 0.22, and percentage of polymorphic loci, P = 66.7) than did form IG and form MA (H = 0.08 in both, and P = 25.0 and 33.3, respectively). Form MA and form IG are genetically more similar to each other than both are to form CM. Based on wing morphology, estimates of F statistics, and genetic similarities, we propose that An. albitarsis in Brazil is a species complex. It comprises at least two morphologically distinguishable species: (1) An. deaneorum (currently one taxon) and (2) the An. marajoara species complex, which further consists of at least three cryptic forms, marajoara form MA, marajoara form IG, and marajoara form CM.

Malaria vectors in the Brazilian Amazon: Anopheles of the subgenus Nyssorhynchus

“…Some anophelines were individually tested but most of them were tested in groups of up to 10 selected according to species, location, date and hour of capture. For studies of species complexes, morphological characters, chromosomal 12 and electrophoretic techniques 21 as well as ribosomal 10 and mitochondrial DNA analyses 13 were utilized on both immature and adult anophelines.…”

Genetic Structure of Anopheles (Nyssorhynchus) marajoara (Diptera: Culicidae) in Colombia

“…Three allopatric populations were detected, with a noteworthy heterozygote deficit and unique haplotypes in each of the populations studied. 12 The second study, using the whole mtCOI gene, 13 found multiple signatures of a demographic expansion event in the eastern Brazilian Amazon. More recently, a third study was done.…”

Genetic divergence in mitochondrial DNA of Anopheles nuneztovari (Diptera: Culicidae) from Brazil and Colombia

“…The high rate of substitution in mtDNA makes it a powerful tool to address evolutionary questions, especially for those groups which include recently evolved taxa, such as the anopheline mosquitoes. The restriction patterns of mtDNA were used to distinguish the isomorphic species A, B, C and D of the A. dirus complex (Yasothornsrikul et al, 1988), as well as species of the A. quadrimaculatus (Mitchell et al, 1992) and A. albitarsis (Narang et al, 1993) complexes. At the intraspecific level, mtDNA studies have enabled the estimation of intra-and interpopulational variability, sequence divergence, and historical and phylogeographic patterns, as well as the degree of gene flow in A. aquasalis (Conn et al, 1993a), A. quadrimaculatus, A species (Perera et al, 1995), A. darlingi (Freitas-Sibajev et al, 1995;Conn et al, 1999), A. gambiae and A. arabiensis Besansky et al, 1997), A. rangeli and A. trinkae (Conn et al, 1997) and A. nuneztovari .…”