title: Molecular characterization and identification of members of the Anopheles subpictus complex in Sri Lanka.
abstract: BACKGROUND
  Anopheles subpictus sensu lato is a major malaria vector in South and Southeast Asia. Based initially on polytene chromosome inversion polymorphism, and subsequently on morphological characterization, four sibling species A-D were reported from India. The present study uses molecular methods to further characterize and identify sibling species in Sri Lanka.
  
  
  METHODS
  Mosquitoes from Sri Lanka were morphologically identified to species and sequenced for the ribosomal internal transcribed spacer-2 (ITS2) and the mitochondrial cytochrome c oxidase subunit-I (COI) genes. These sequences, together with others from GenBank, were used to construct phylogenetic trees and parsimony haplotype networks and to test for genetic population structure.
  
  
  RESULTS
  Both ITS2 and COI sequences revealed two divergent clades indicating that the Subpictus complex in Sri Lanka is composed of two genetically distinct species that correspond to species A and species B from India. Phylogenetic analysis showed that species A and species B do not form a monophyletic clade but instead share genetic similarity with Anopheles vagus and Anopheles sundaicus s.l., respectively. An allele specific identification method based on ITS2 variation was developed for the reliable identification of species A and B in Sri Lanka.
  
  
  CONCLUSIONS
  Further multidisciplinary studies are needed to establish the species status of all chromosomal forms in the Subpictus complex. This study emphasizes the difficulties in using morphological characters for species identification in An. subpictus s.l. in Sri Lanka and demonstrates the utility of an allele specific identification method that can be used to characterize the differential bio-ecological traits of species A and B in Sri Lanka.
authors.affiliation: Department of Zoology, Faculty of Science, University of Jaffna, Jaffna 40000, Sri Lanka. noble@jfn.ac.lk.
authors.forename: Sinnathamby N
authors.initials: SN
authors.lastname: Surendran
authors.forename: Devojit K
authors.initials: DK
authors.lastname: Sarma
authors.forename: Pavilupillai J
authors.initials: PJ
authors.lastname: Jude
authors.forename: Petri
authors.initials: P
authors.lastname: Kemppainen
authors.forename: Nadarajah
authors.initials: N
authors.lastname: Kanthakumaran
authors.forename: Kanapathy
authors.initials: K
authors.lastname: Gajapathy
authors.forename: Lalanthika B S
authors.initials: LB
authors.lastname: Peiris
authors.forename: Ranjan
authors.initials: R
authors.lastname: Ramasamy
authors.forename: Catherine
authors.initials: C
authors.lastname: Walton
mesh_terms: D000818:Animals; D000852:Anopheles / Q000033:anatomy & histology / Q000145:classification* / Q000235:genetics*; D016000:Cluster Analysis; D045304:Cytochromes c / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D004199:Disease Vectors; D005260:Female; D005838:Genotype; D006239:Haplotypes; D008969:Molecular Sequence Data; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D013188:Sri Lanka
chemical_list: D021903:DNA, Ribosomal Spacer; D045304:Cytochromes c