CHRISTOPHER A. GREENLEONARD E. MUNSTERMANNS. G. TANSAKOL PANYIMVISUT BAIMAIMahidol UniversityUniversity of Notre DameUniversiti Putra Malaysia2018-08-102018-08-101992-01-01Medical and Veterinary Entomology. Vol.6, No.1 (1992), 29-36136529150269283X2-s2.0-0026456473https://repository.li.mahidol.ac.th/handle/20.500.14594/22247Abstract. Mixtures of chromosomal forms A, B, C and D in natural populations of Anopheles dirus Peyton & Harrison sensu lato in Thailand show significant positive values of Wright's fixation index for six enzyme‐electromorph loci. The mean value of FIS over all loci was found to be +0.28 (SD 0.02), with a range of +0.57 (Odh) to +0.10 (Idh‐2). Partitioning electromorph data for the chromosomal forms reduces the mean FIS to 0.03 (SD 0.01), which suggests that positive assortative mating is a characteristic of each form. This supports the hypothesis that the chromosomal/electrophoretic forms A, B, C and D represent four distinct biological species within the An.dirus complex. An example is given of the use of enzyme electromorphs as a means of vector identification during a malaria entomological field study involving a mixture of An.dirus species A and D. Electromorph identifications of 323 sp. A and 161 sp. D were more than 98% correct when cross‐referenced to specific DNA probes. Copyright © 1992, Wiley Blackwell. All rights reservedMahidol UniversityAgricultural and Biological SciencesImmunology and MicrobiologyVeterinaryArticleSCOPUS10.1111/j.1365-2915.1992.tb00031.x