Description of a new relict eriophyoid mite, Loboquintus subsquamatus n. gen. & n. sp (Eriophyoidea, Phytoptidae, Pentasetacini) based on confocal microscopy, SEM, COI barcoding and novel CLSM anatomy of internal genitalia

A new pentasetacine mite Loboquintus subsquamatus n. gen. & n. sp. was found living under scale-like leaves of 2-3 years old twigs of Cupressus sempervirens in Montenegro. This mite species possesses a number of morphological features (uncommon teardrop-shaped body, traits of prosoma, atypical primitive anatomy of the genital apparatus and morphological traits of immatures) which clearly distinguish it from all other known eriophyoids. Adults of L. subsquamatus have seta vi situated on the anterior margin of a uniquely elongate lingua-like thin frontal lobe, three pits on the posterior prodorsal shield margin, a remarkable tube-like structure in the basal part of gnathosoma, a complicated three-layered epigynium, spermathecae directed antero-laterad, short spermathecal tubes and setae eu suppressed in males and possibly expressed in females. External genitalia of males and females of L. subsquamatus are fundamentally similar. Hypothesized remnants of coxisterna III or IV (forming a postgenital plate) are remarkably distinct in males. Two new morphometrical variables are proposed to supplement the CLSM protocol for description of internal genitalia of eriophyoids proposed by Chetverikov et al. (Zootaxa 3560:41-60, 2012b): (a) the length of ventral projection of the transvers genital apodeme and (b) the length of the posterior (=postspermathecal) part of the longitudinal bridge which in L. subsquamatus is remarkably long, whereas in many other eriophyoids it is reduced

Basal divergence of Eriophyoidea (Acariformes, Eupodina) inferred from combined partial COI and 28S gene sequences and CLSM genital anatomy

Eriophyoids are an ancient group of highly miniaturized, morphologically simplified and diverse phytoparasitic mites. Their possible numerous host-switch events have been accompanied by considerable homoplastic evolution. Although several morphological cladistic and molecular phylogenetic studies attempted to reconstruct phylogeny of Eriophyoidea, the major lineages of eriophyoids, as well as the evolutionary relationships between them, are still poorly understood. New phylogenetically informative data have been provided by the recent discovery of the early derivative pentasetacine genus Loboquintus, and observations on the eriophyoid reproductive anatomy. Herein, we use COI and D1-2 rRNA data of 73 eriophyoid species (including early derivative pentasetacines) from Europe, the Americas and South Africa to reconstruct part of the phylogeny of the superfamily, and infer on the basal divergence of eriophyoid taxa. In addition, a comparative CLSM study of the female internal genitalia was undertaken in order to find putative apomorphies, which can be used to improve the taxonomy of Eriophyoidea. The following molecular clades, marked by differences in genital anatomy and prodorsal shield setation, were found in our analyses: Loboquintus(Pentasetacus((Eriophyidae + Diptilomiopidae)(Phytoptidae-1, Phytoptidae-2))). The results of this study suggest that the superfamily Eriophyoidea comprises basal paraphyletic pentasetacines (Loboquintus and Pentasetacus), and two large monophyletic groups: Eriophyidae s.l. [containing paraphyletic Eriophyidae sensu Amrine et al. 2003 (=Eriophyidae s.str.) and Diptilomiopidae sensu Amrine et al. 2003] and Phytoptidae s.l. [containing monophyletic Phytoptidae sensu Boczek et al. 1989 (=Phytoptidae s.str.) and Nalepellidae sensu Boczek et al. 1989]. Putative morphological apomorphies (including genital and gnathosomal characters) supporting the clades revealed in molecular analyses are briefly discussed