Anthony Susan E, Sinclair Brent J
Physiol Biochem Zool. 2019 Mar/Apr;92(2):201-205. doi: 10.1086/702655.
Although many arthropods are freeze tolerant (able to withstand internal ice), small-bodied terrestrial arthropods such as mites are thought to be constrained to freeze avoidance. We field-collected active adult red velvet mites, Allothrombium sp. (Trombidiidae), in winter in Southwestern Ontario, Canada, where temperatures drop below -20°C. These mites froze between -3.6° and -9.2°C and survived internal ice formation. All late-winter mites survived being frozen for 24 h at -9°C, and 50% survived 1 wk. The lower lethal temperature (LLT; low temperature that kills 50% of mites) was ca. -20°C in midwinter. Hemolymph osmolality and glycerol concentration increased in midwinter, accompanied by decreased water content. Thus, this species is freeze tolerant, demonstrating that there is neither phylogenetic nor size constraint to evolving this cold tolerance strategy.
尽管许多节肢动物具有耐冻性（能够承受体内结冰），但人们认为小型陆生节肢动物，如螨虫，只能避免结冰。我们于冬季在加拿大安大略省西南部野外采集了活跃的成年红绒螨（Allothrombium sp.，绒螨科），那里的温度会降至零下20摄氏度以下。这些螨虫在零下3.6摄氏度至零下9.2摄氏度之间结冰，并在体内形成冰后存活下来。所有冬末的螨虫在零下9摄氏度下被冷冻24小时后都存活了下来，50%的螨虫在冷冻1周后仍存活。冬季中期的低温致死温度（LLT；杀死50%螨虫的低温）约为零下20摄氏度。冬末血淋巴渗透压和甘油浓度增加，同时含水量降低。因此，该物种具有耐冻性，表明在进化这种耐寒策略方面，既没有系统发育限制，也没有体型限制。
