Cytogenetic, hybridization and molecular evidence of four cytological forms of Anopheles nigerrimus (Hyrcanus Group) in Thailand and Cambodia. Issue 2 (December 2013)

• Record Type: Journal Article
• Authors: Songsawatkiat, Siripan; Baimai, Visut; Saeung, Atiporn; Thongsahuan, Sorawat; Otsuka, Yasushi; Srisuka, Wichai; Choochote, Wej
• Is Part Of: Journal of vector ecology. Volume 38:Issue 2(2013:Dec.)
• Page Start: 266
• Page End: 276
• Publication Date: 2013-12
• Subjects: Arthropod vectors -- Ecology -- Periodicals; Animals as carriers of disease -- Periodicals; Animal ecology -- Periodicals; Host-parasite relationships -- Periodicals; Pests -- Control -- Periodicals; 571.986
• DOI: 10.1111/j.1948-7134.2013.12040.x
• Languages: English
• ISSNs: 1081-1710

Abstract

<abstract abstract-type="main"> <title>ABSTRACT</title> <p>Thirteen isoline colonies of <italic>Anopheles nigerrimus</italic> were established from individual wild‐caught females collected from cow‐baited traps at locations in Thailand and Cambodia. Three types of X (X<sub>1</sub>, X<sub>2</sub>, X<sub>3</sub>) and 4 types of Y (Y<sub>1</sub>, Y<sub>2</sub>, Y<sub>3</sub>, Y<sub>4</sub>) chromosomes were recovered, according to differing amounts of extra heterochromatin. Four karyotypic forms were designed depending upon apparently distinct figures of X and Y chromosomes, i.e., Form A (X<sub>1</sub>, X<sub>2</sub>, X<sub>3</sub>, Y<sub>1</sub>), B (X<sub>2</sub>, X<sub>3</sub>, Y<sub>2</sub>), C (X<sub>1</sub>, Y<sub>3</sub>), and D (X<sub>3</sub>, Y<sub>4</sub>). Forms C and D were new metaphase karyotypes discovered in this study. Form A appeared to be common in both Thailand and Cambodia. Forms B and D were found to be rather specific to southern and northeastern Thailand, respectively, whereas Form C was confined to Cambodia. Hybridization experiments among the eight isoline colonies, which were representative of four karyotypic forms of <italic>An. nigerrimus</italic>, demonstrated genetic compatibility in giving viable progenies and synaptic salivary gland polytene chromosomes through F<sub>2</sub>‐generations. These results elucidated the conspecific relationship, comprising four cytological forms within this taxon. Supportive evidence was confirmed further by very low intraspecific sequence variations (average genetic distance = 0.002–0.007) of the nucleotide sequences in ribosomal DNA [second internal transcribed spacer (ITS2)] and mitochondrial DNA [cytochrome <italic>c</italic> oxidase subunit I (COI) and subunit II (COII)].</p> </abstract>