TY  - JOUR
JF  - Acarologia
T1  - Morphological adaptations of phytoseiid predatory mites (Acari: Mesostigmata) to overwintering sites
VL  - 66
IS  - Suppl
SP  - 164
EP  - 164
PY  - 2026
SN  - 0044-586X
SN  - 2107-7207
PB  - Les Amis d'Acarologia
AU  - Farid, Faraji
UR  - https://doi.org/10.24349/vbip-lepg
DO  - 10.24349/vbip-lepg
DA  - 2026-07-20
ET  - 2026-07-20
KW  - Morphology
KW  - Overwintering
KW  - Phytoseiidae
KW  - Refuge sites
KW  - Temperate zones
AB  - To identify the morphological adaptations in phytoseiid predatory mites associated with overwintering in refuge spaces. During the autumn and winter seasons of 2020–2025, various parts of trees, weeds, and soil were examined to identify the overwintering sites of Phytoseiidae. Relevant literature and SEM images were also reviewed. Leaf litter, bark and woody plant structures, evergreen plants, and weeds serve as natural winter refuges. On deciduous trees in cold temperate zones, phytoseiid predatory mites hide in acute-angled or tight parallel microhabitats such as cracks and crevices in tree bark, under loose bark scales, and within bud scales or around dormant buds of trees and shrubs. A high degree of adaptation and synchronization among different body parts allows phytoseiids to fit well within such spaces. Flattened bodies, gradual increases in the length of dorsal shield setae toward the posterior and lateral margins, the direction of seta j1 (forward) relative to j3 (backward), longer JV5 ventral seta, curvature of legs I–IV that remain at the level of the dorsal shield, having more setae on dorsal side of the tibiae and genua I-IV (set often on tubercles) and not having macrosetae on the tibiae and genua II-III can be considered adaptive morphological traits. Most species of the subfamily Typhlodrominae in cold temperate zones exhibit these features. Species of Phytoseius (subfamily Phytoseiinae), which are mainly tree-inhabiting predatory mites, display a unique morphology of thickened dorsal shield setae Z4 (curved up and forward) and Z5 (curved up and backward). This characteristic represents an adaptation that facilitates fixing and fitting into acute angles during overwintering. Most species of the subfamily Amblyseiinae (except for Euseius finlandicus and Kampimodromus spp.) overwinter in leaf litter and plant debris. Amblyseius and Proprioseiopsis species, characterized by long s4, Z4, and Z5 setae with other setae being short or minute, having erected macrosetae on legs II-IV, as well as relatively larger, pear-shaped bodies, show adaptations to their heterogeneous habitats. Some Neoseiulus species exhibit features similar to those of Typhlodromus. As shown by Kawashima and Jung (2010), in weeds with rosette-type leaves, Neoseiulus californicus overwinters between leaf bases that form acute angles. More data, especially direct observations and SEM images, are needed to better understand the body posture and configuration of different body parts when the phytoseiid predatory mites are positioned within refuge sites.
ER -