Kahl O, Knülle W
Institut für Angewandte Zoologie, Freie Universität Berlin, West Germany.
Exp Appl Acarol. 1988 Feb;4(1):73-83. doi: 10.1007/BF01213843.
Contrary to current opinion, fully engorged and detached larvae and nymphs of some ixodid ticks consistently take up substantial amounts of atmospheric water vapour and thereby display their regulative capacity for maintaining water balance in subsaturated air. Net uptake of vapour generally begins some days after detachment and the capability persists until shortly after initiation of apolysis, a period which in diapausing specimens may extend up to several months. This was shown for Ixodes ricinus, Haemaphysalis punctata, and the North American I. dammini. Apparently, some other engorged ixodid immatures fail to exhibit net vapour uptake, as was shown for both larvae and nymphs of Dermacentor marginatus and nymphs of Hyalomma anatolicum excavatum. But there is some evidence for engorged nymphs of D. marginatus that active uptake of vapour does occur, masked by spiracular transpiration. Net uptake of vapour is apparently not possible during the pharate phases. In I. ricinus both teneral nymphs and adults are capable of achieving net water gains by active vapour uptake on the first day following ecdysis. There is new evidence from fully engorged I. ricinus immatures for the decisive role of agranular alveoli in the production of the salivary secretion involved in vapour uptake.
与当前观点相反，一些硬蜱科蜱虫完全饱血并脱离宿主的幼虫和若虫持续摄取大量大气中的水蒸气，从而展现出它们在亚饱和空气中维持水平衡的调节能力。水蒸气的净摄取通常在脱离宿主几天后开始，这种能力一直持续到蜕皮开始后不久，在滞育标本中，这段时间可能长达数月。蓖麻硬蜱、微小牛蜱和北美达敏硬蜱都有此现象。显然，其他一些饱血的硬蜱科未成熟蜱虫未表现出净水蒸气摄取，边缘革蜱的幼虫和若虫以及小亚璃眼蜱的若虫都是如此。但有证据表明，边缘革蜱的饱血若虫存在水蒸气的主动摄取，只是被气门蒸腾掩盖了。在预成虫期显然无法进行水蒸气的净摄取。在蓖麻硬蜱中，羽化后的若虫和成虫在蜕皮后的第一天都能够通过主动摄取水蒸气实现净水分增加。有来自饱血的蓖麻硬蜱未成熟蜱虫的新证据表明，无颗粒小泡在摄取水蒸气所涉及的唾液分泌过程中起决定性作用。
