Omer S M, Cloudsley-Thompson J L
Bull World Health Organ. 1970;42(2):319-30.
The dry-season biology of a member of the Anopheles gambiae complex (probably species B) was studied in 2 areas in the Khartoum region of Sudan. It was found that in the valley of the White Nile the species maintained itself by low-level breeding, as shown by the continuing presence of larvae, male mosquitos and parous females through the dry months (9 months in the year). In the scattered villages of arid areas situated more than 20 km from the Nile Valley, on the other hand, regular sampling through the cool dry and hot dry months of the year failed to detect any An. gambiae except nulliparous females. These were found in occupied huts, deserted huts, dry wells and animal burrows.The great majority of 213 females collected in the 11 dry months between November 1966 and December 1967 had fresh or older blood-meals but the abdomen was never found fully distended in the dry season. Examination of the ovaries showed that they did not develop beyond Christophers' stage II in the period from November to February, stage III in March and April, or beyond stage IV in May. But, in June and July stage IV and V ovaries predominated and few specimens remained in stage late-II.It is inferred from these observations that the local population of An. gambiae is highly adapted to survive in the adult stage through the severe drought and heat of the arid zone of Sudan. Some feeding activity continues but ovarian development is extremely retarded, and only one batch of eggs matures during the whole 9-month period. Evidence collected in the Nile Valley indicated that female An. gambiae in that area were not subjected to similar retardation of the ovarian cycle; in fact, clear evidence was obtained there of continuous year-round breeding by the mosquito.
在苏丹喀土穆地区的两个地点，对冈比亚按蚊复合体的一个成员（可能是B种）的旱季生物学特性进行了研究。结果发现，在白尼罗河谷，该物种通过低水平繁殖得以维持，这表现为在旱季的几个月（一年中有9个月）里，幼虫、雄蚊和已产卵雌蚊持续存在。另一方面，在距离尼罗河谷20多公里的干旱地区的零散村庄，在一年中凉爽干燥和炎热干燥的月份进行定期采样，除了未产卵雌蚊外，未检测到任何冈比亚按蚊。这些未产卵雌蚊在有人居住的小屋、废弃的小屋、枯井和动物洞穴中被发现。在1966年11月至1967年12月的11个旱季月份里收集的213只雌蚊中，绝大多数都有新鲜或较陈旧的血餐，但在旱季从未发现腹部完全膨胀。对卵巢的检查表明，在11月至2月期间，卵巢发育未超过克里斯托弗斯II期，3月和4月为III期，5月未超过IV期。但是，在6月和7月，IV期和V期卵巢占主导地位，很少有标本停留在II期末期。从这些观察结果可以推断，苏丹干旱地区的当地冈比亚按蚊种群高度适应在成年阶段度过严重的干旱和炎热。一些取食活动仍在继续，但卵巢发育极度迟缓，在整个9个月期间只有一批卵成熟。在尼罗河谷收集的证据表明，该地区的冈比亚按蚊雌蚊没有受到类似的卵巢周期迟缓影响；事实上，在那里获得了该蚊子全年持续繁殖的明确证据。
