Increased fecundity associated with infection by a Cytophaga–like intracellular bacterium in the predatory mite, Metaseiulus occidentalis

The endosymbiont Wolbachia has gained widespread notoriety over the past decade because of its high infection frequency among arthropods, and the unique heterogeneity of the host reproductive effects that it has been implicated as causing to enhance its own spread. Recently, another endosymbiotic bacterium from the Cytophaga–Flavobacterium–Bacteroides phylum has been shown to be widespread among arthropods and manipulate its hosts' reproduction to enhance its own spread. We show that infection by this Cytophaga–like organism (CLO) in the predatory mite Metaseiulus occidentalis (Acari: Phytoseiidae) is associated with a significant increase in the fecundity of infected females. This adds to the growing list of phenotypes that the CLO can induce in its hosts, which now include feminization, parthenogenesis induction, cytoplasmic incompatibility and fecundity enhancement, rivalling Wolbachia for overall diversity of host reproductive manipulations.