Departamento de Conservación de la Biodiversidad, El Colegio de la Frontera Sur (ECOSUR), Avenida Centenario Km 5.5, Chetumal 77014, Quintana Roo, Mexico.
Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 118 route de Narbonne, 31062 Toulouse Cedex 09, France.
Sci Rep. 2016 Jul 21;6:29995. doi: 10.1038/srep29995.
Mites are frequent ant symbionts, yet the exact nature of their interactions with their hosts is poorly known. Generally, myrmecophilous mites show adaptations for dispersal through phoresis, but species that lack such an adaptation may have evolved unusual specialized relationships with their hosts. The immature stages of Macrodinychus multispinosus develop as ectoparasitoids of pupae of the invasive ant Paratrechina longicornis. Feeding stages show regressed locomotor appendages. These mites complete their development on a single host, sucking all of its body content and therefore killing it. Locally high proportions of parasitized host pupae suggest that M. multispinosus could serve as a biological control agent. This is the ninth species of Macrodinychus reported as ant parasite, and the third known as parasitoid of invasive ants, confirming a unique habit in the evolution of mite feeding strategies and suggesting that the entire genus might be parasitic on ants. Several mites' characteristics, such as their protective morphology, possible viviparity, lack of a specialized stage for phoretic dispersal, and low host specificity, combined with both the general low aggressiveness of invasive P. longicornis towards other ants and its possible susceptibility to generalist ectoparasites would account for the host shift in native macrodinychid mites.
螨虫是蚂蚁的常见共生体，但它们与宿主的确切相互作用性质知之甚少。一般来说，拟蚁螨具有通过 phoresis 进行扩散的适应能力，但缺乏这种适应能力的物种可能与它们的宿主进化出了不寻常的特殊关系。Macrodinychus multispinosus 的幼虫期发育为入侵蚂蚁 Paratrechina longicornis 的蛹外寄生蜂。取食阶段表现出退化的运动附肢。这些螨虫在单个宿主上完成发育，吸食其所有的身体内容物，从而杀死它。寄生的宿主蛹的局部高比例表明，M. multispinosus 可以作为生物防治剂。这是第九种被报道为蚂蚁寄生虫的 Macrodinychus 物种，也是第三种已知的入侵蚂蚁寄生蜂，证实了螨虫取食策略进化中的独特习性，并表明整个属可能以蚂蚁为寄生对象。一些螨虫的特征，如它们的保护形态、可能的胎生、缺乏用于 phoretic 扩散的专门阶段以及宿主特异性低，再加上入侵的 P. longicornis 对其他蚂蚁的一般攻击性较低及其对节肢动物通用外寄生虫的可能易感性，解释了原生 Macrodinychus 螨的宿主转移。
