Generic Concept of the Phytoseiids (Acari: Phytoseiidae) according to Athias-Henriot

The economic importance of the Phytoseiidae motivated many scientists to work on the systematics of this family. One of them was the French acarologist Claire Athias-Henriot. In her first work, she tackled the question of supraspecific groupings within this family from an evolutionistic point of view, and suggested a system for numbering dorsal shield setae, that could be applied to both hypotrichous and holotrichous forms. She also looked for other characters, such as the ratios of the distance between the insertions of some setae on dorsal and sternal shields, the presence of macrosetae on legs, and the length/width ratio of the ventrianal shield. Following Dosse (1957; 1958) who used the shape of the insemination apparatus (spermatheca) for taxonomic purposes, she also adopted this character to define genera, initially without giving it a particular weight. Meanwhile, she also studied other gamasids, and in 1966 considered the insemination apparatus as the main character for distinguishing families of Gamasida. She distinguished the Phytoseiidae within the Laelapoidea (sic), by the type of insemination apparatus and the dorsal hypotrichy. In 1966, she adopted Lindquist and Evans (1965) chaetotactic nomenclature system in her "Contribution \ue0 l\u2019\ue9tude des Amblyseius pal\ue9arctiques (Acariens anactinotriches, Phytoseiidae)". In 1967, she advanced the hypothesis that the insemination apparatus was best for defining phylogenetic relationships because it was less subject to hereditary modifications than external body parts that are in direct contact with the environment. One year later, Athias-Henriot published an exhaustive study on the insemination apparatus of Laelapoidea stating the taxonomic importance of this structure. She also studied adenotaxy and sigillotaxy in order to find characters to define natural lineages. In 1975, she studied the dorsal organotaxy of Amblyseiini in order to define species characters. Two years later she redefined the genus Cydnodromus emphasizing both the importance of the insemination apparatus and the evolution of solenostome gv3. In 1978 and 1981, while describing respectively the new genera Dictydionotus and Pegodromus, Athias-Henriot considered the insemination apparatus and the other characters as having the same weight. In 1983, Ragusa and Athias-Henriot redescribed the genus Neoseiulus; in this case the insemination apparatus was considered as the main character for the definition of the genus, with a series of other (related) characters