Abstract

It is widely accepted in literature that members of Diptilomiopidae possess a “long-form” oral stylet which is usually nearly as long as the cheliceral stylets. However, it is not only the length of the oral stylet itself that is the character to discriminate diptilomiopids, but also its shape and the orientation of the pharynx. We reinvestigated the gnathosoma of Rhyncaphytoptus longipalpis Xue et Hong, 2005, a “diptilomiopid” species from China, and demonstrated that this mite has an angled short-form oral stylet and an almost horizontally oriented pharynx, which is not typical for Diptilomiopidae. We reassign “longipalpis” to a new genus Bambusacarus n. gen. in a different family-group (Eriophyidae, Phyllocoptinae, Anthocoptini) and provide a supplementary description of this species based on the material from Hungary where it was found on six introduced bamboo species of the genus Phyllostachys (Poaceae). Similar to members of endoparasitic genus Novophytoptus (Phytoptidae), B. longipalpis n. comb. has elongate, forceps-shaped gnathosomal structures and it lacks setae d and v on palps. We conclude that in some “non-diptlilomiopid” lineages of Eriophyoidea (1) the elongation of palps and changing of the length and curvature of the gnathosomal stylets may not be correlated with transformation of the shape of the oral stylet and reorientation of pharynx, and (2) when this happens, the mite homoplastically acquires the well-recognized “diptilomiopid-like” phenotype as seen in B. longipalpis n. comb. In future, careful reinvestigation of the shape of the oral stylet in Diptilomiopidae may reveal new examples of similar phenotypic convergency in Eriophyoidea.