A revision of the tribe Phytoseiini Berlese with a world review of the purseglovei species group in the genus Phytoseius Ribaga (Acari: Phytoseiidae)

Abstract

The complete absence of setae in the S-series on the adult dorsal opisthoscutum is a synapomorphy which distinguishes the species in the tribe Phytoseiini Berlese from those in the tribe Typhlodromini Karg. The tribe Phytoseiini contains only one genus, Phytoseius Ribaga, and 143 known species, which are among the most hypotrichous in the family Phytoseiidae. The presence/absence of the only variable dorsal setae in the genus, J2 and R1, produces 3 dorsal setal patterns and these are the basis for 3 proposed species groups. The 3 species groups are: the plumifer group with 40 species; the purseglovei group with 9 species; and the horridus group with 94 species. The idiosomal setal patterns, based on the combined dorsal and ventral patterns, are known for the females of 136 species and for the males of 47 species. The probable evolution of the 3 groups and the setal patterns in the genus Phytoseius are discussed. Keys to the adult females of the 3 species groups in the genus Phytoseius and to the species in the purseglovei group are provided. Descriptions of each species in the purseglovei group also are given. Phytoseius taianensis Liang and Ke is designated as a new junior synonym and P. cotini Wang and Xu as a provisional junior synonym of P. aleuritius Wu.