THE BIOLOGY OF SIMULIUM ARCTICUM MALLOCH IN ALBERTA. PART I. OBLIGATE ANAUTOGENY IN S. ARCTICUM AND OTHER BLACK FLIES (DIPTERA: SIMULIIDAE)

Abstract

AbstractThe primary follicles of all 291 laboratory-reared Simulium arcticum Malloch females provided with only sucrose and water did not develop beyond stage II. This was true for flies derived from field-collected eggs, larvae, or pupae, and for laboratory-reared larvae that received either standard, concentrated, or unsupplemented river water diets. Conversely, all 59 females that digested a meal of cattle blood had follicles at stage IV by 85 h and stage V (mature eggs) by 109 h post-engorgement. Simulium arcticum populations from the Athabasca and Crowsnest River were thus characterized by obligate anautogeny and gonotrophic concordance. Most non-blood-fed females were dissected and examined when 4–19 days old. The presence or absence of a meconium, quantity of fat body, and other internal features were compared in young and old non-blood-fed females.