Systematic relationships and the evolution of some life history aspects in the mite genus Ensliniella Vitzthum, 1925 (Acari: Winterschmidtiidae)

Abstract

A phylogenetic analysis of relationships is carried out for the species of the mite genus Ensliniella Vitzthum, 1925, all of which are associated with eumenine vespid wasps of the genus Allodynerus Blüthgen. Vespacarus Baker and Cunliffe, 1960, Kennethiella Cooreman, 1954 and Monobiacarus Baker and Cunliffe, 1960 are used as outgroups, following the results of an analysis of generic relationships in the study group. The genus Ensliniella is revised, two new species are described, and the previously known species are redescribed. The resutls suggest that the characteristic of producing a second type of male (small type male) evolved in the ancestor of Kennethiella, Vespacarus and Ensliniella, probably for adaptive reasons. Its maintenance in the latter two genera however, is hypothesized to be the result of phylogenetic inertia, rather than some adaptive function. The feeding behaviour in the ancestor of Kennethiella, Vespacarus and Ensliniella changed from feeding off the host, to feeding on the host larva and pupa, while the behaviour of never leaving the host originated in the Vespacarus-Ensliniella lineage. Host specificity within Ensliniella and the other genera in the study group is very high. Individual species of Ensliniella occur only on a single host, even if several potential host species are sympatric. The available data suggest cospeciation as a possible explanation for the host association patterns within Ensliniella, but colonization has to be invoked to explain the pattern of association at the generic level.

Keywords :

• Phylogenetics
• cospeciation
• Acari
• Winterschmidtiidae
• Ensliniella
• Vespidae
• Eumeninae