Lindsley & Grell, 1972, p. 18
origin: X ray induced in In(2R)Cy; In(3R)P. (The first X-ray-induced mutation recovered in the USSR.)
discoverer: Serebrovsky, 28a.
synonym: Xa.
references: Serebrovsky and Dubinin, 1930, J. Heredity 21: 259-65.
phenotype: Wings reduced in length to about 70 percent normal; irregular in outline with a V-shaped incision with apex at L2, uniformly present, giving wing a mittenlike shape with the thumb between marginal vein and L2. Excellent dominant with no overlap. Fertile and fully viable in heterozygote. Usually lethal in homozygous conditions, but occasionally ecloses very late as pale dwarf with wings and balancers like vg. Waddington reports deep notch visible in tip of wing fold in prepupa [1939, Proc. Natl. Acad. Sci. U.S. 25: 299-307; 1940, J. Genet. 41: 75-139 (fig.)]. In homozygotes and in combination with ap4, ap6, or M(2)S24 wings are straplike and 30-70 percent normal length, and haltere length is 25-50 percent normal; longevity, fertility like ap4/ap4 except for an occasional long-lived apXa/M(2)S24 female that may be fertile (Schultz; Butterworth and King). apXa/apblt has combined phenotypes of apXa/+ and apblt/apblt (Schultz). RK1A.
cytology: Shown by Sturtevant (1934, DIS 2: 19) to be associated with T(2;3)apXa = T(2;3)41F; 89E8-Fl which is superimposed on In(2R)Cy and In(3R)P (Morgan, Bridges, and Schultz, 1936, Carnegie Inst. Wash. Year Book 35: 294; Lewis, 1951, DIS 25: 109).
color figure: P. A. Otto (original)
b & w figure: Bridges and Brehme, 1944, Carnegie lnst. Wash. Publ. No. 552: 228 (original drawn by Edith M. Wallace)