Atypically Shaped Setae in Gall Mites (Acariformes, Eriophyoidea) and Mitogenomics of the Genus Leipothrix Keifer (Eriophyidae).

The setae in Eriophyoidea are filiform, slightly bent and thickened near the base. Confocal microscopy indicates that their proximal and distal parts differ in light reflection and autofluorescence. Approximately 50 genera have atypically shaped setae: bifurcated, angled or swollen. These modifications are known in the basal part of prosomal setae u', ft', ft″, d, v, bv, ve, sc and caudal setae h2. We assessed the distribution of atypically shaped setae in Eriophyoidea and showed that they are scattered in different phylogenetic lineages. We hypothesized that the ancestral setae of eriophyoid mites were bifurcated before later simplifying into filiform setae. We also proposed that hypo-furcating setae are a synapomorphy that unites Eriophyoidea with Nematalycidae. We analyzed four new mitochondrial genomes of Leipothrix, the largest genus with bifurcated d, and showed that it is monophyletic and has a unique mitochondrial gene order with translocated trnK. We exclude Cereusacarus juniperensisn. comb. Xue and Yin, 2020 from Leipothrix and transfer five Epitrimerus spp. to Leipothrix: L. aegopodii (Liro 1941) n. comb., L. femoralis (Liro 1941) n. comb., L. geranii (Liro 1941) n. comb., L. ranunculi (Liro 1941) n. comb., and L. triquetra (Meyer 1990) n. comb.

Integrative Taxonomy of the Gall Mite Nothopoda todeica n. sp. (Eriophyidae) from the Disjunct Afro-Australasian Fern Todea barbara: Morphology, Phylogeny, and Mitogenomics.

Eriophyoidea is a group of phytoparasitic mites with poorly resolved phylogeny. Previous studies inferred Eriophyidae s.l. as the largest molecular clade of Eriophyoidea, and Nothopodinae as the basal divergence of Eriophyidae s.l. We investigate the morphology and molecular phylogeny of Nothopoda todeican. sp. (Nothopodinae, Nothopodini), associated with a disjunct Afro-Australasian fern Todea barbara (Osmundaceae) from South Africa. Our analyses (1) determine new erroneous sequences (KF782375, KF782475, KF782586) wrongly assigned to Nothopodinae instead of Phyllocoptinae, (2) confirm the basal position of Nothopodinae in Eriophyoidea s.l., (3) question the monophyly of the Colopodacini and Nothopodini tribes, and (4) show the nested position of African fern-associated Nothopoda within a clade dominated by Asian nothopodines from angiosperms, which implies (a) a secondary association of nothopodines with ferns and (b) no relation between geography (continents) and the phylogenetic relationships of Nothopodinae species. Finally, we obtained a first complete mitochondrial genome for Nothopodinae and revealed a new gene order in the mitogenome of N. todeican. sp., notably deviating from those in other investigated eriophyoids. Our results contribute to resolving the phylogeny of Eriophyoidea and provide an example of an integrative study of a new taxon belonging to an economically important group of acariform mites.

Molecular phylogeny of the phytoparasitic mite family Phytoptidae (Acariformes: Eriophyoidea) identified the female genitalic anatomy as a major macroevolutionary factor and revealed multiple origins of gall induction.

Phytoptidae s.str. is a lineage of eriophyoid mites associated with angiosperms. Based on representative taxon sampling and four gene markers (COI, HSP70, 18S, and 28S), we inferred the molecular phylogeny of this group and performed comparative analyses of cuticle-lined female internal genitalia. Although basal relationships were unclear, several well supported clades were recovered. These clades were supported by geography, host associations, and female genital anatomy, but contradicted the current morphology-based systematics. The monophyly of each of five conventional supraspecific groupings (Fragariocoptes, Phytoptus, Phytoptinae, Sierraphytoptinae, and Sierraphytoptini) is rejected based on a series of statistical tests. Additionally, four morphological characters (the absence of tibial solenidion φ and opisthosomal seta c1, presence of telosomal pseudotagma, and 'morphotype') were found to be homoplasies that cannot be used to confidently delimit supraspecific lineages of phytoptids. However, our molecular topology was highly congruent with female genital characters. Eight molecular clades were unambiguously supported by the shapes and topography of the spermathecal apparatus and genital apodemes. This suggests that the female genital anatomy could be an important factor affecting cladogenesis in Phytoptidae, a conclusion contrasting with the general expectation that host characteristics should be a major macroevolutionary force influencing the evolution of host-specific symbionts. Indeed, despite the high host-specificity, there were no apparent cophylogenetic patterns. Furthermore, we show that gall-inducing ability evolved multiple times in phytoptids. Because gall formation creates nearly instantaneous niche partitioning and the potential loss or reduction of gene flow, we hypothesize that it could be an important evolutionary factor affecting speciation within different host-associated clades of phytoptid mites.

Gnathosomal interlocking apparatus and remarks on functional morphology of frontal lobes of eriophyoid mites (Acariformes, Eriophyoidea).

Comparative study of eriophyoid mite gnathosomata using different microscopic techniques shows presence of new dorsoproximal structures (here described as "interlocking apparatus"), which could consolidate mouthparts in rest (non-feeding) position and during feeding actions. Four types of the interlocking apparatus are described. Differences in the interlocking mechanisms coincide with the results of recent molecular phylogenetic studies of Eriophyoidea and provide additional support for the major clades revealed in those studies. Comparative analysis on the morphology of the frontal lobe of the prodorsal shield shows that mechanical protection of the motivator surrounding area and interlocking apparatus are possibly the primary function of the frontal lobe. Unusual shapes of the frontal lobe in selected eriophyoids (elongated, broadened, notched lobes) might result from additional functions that the frontal lobe can perform, e.g. providing additional guide for palps and stylets, or hermeticity of the space between dorsoproximal palpcoxae during feeding.

CLSM anatomy of internal genitalia of Mackiella reclinata n. sp. and systematic remarks on eriophyoid mites from the tribe Mackiellini Keifer, 1946 (Eriophyoidea: Phytoptidae).

A new mackielline mite, Mackiella reclinata n. sp., from a South African indigenous palm-tree, Phoenix reclinata, is described in detail using different microscopy techniques. A CSLM study of M. reclinata n. sp. internal genitalia shows that mites of this genus possess teardrop shaped spermathecae, sausage-like spermathecal tubes directed anteriad and a subtrapezoidal anterior genital apodeme with a peculiar apical plate, orthogonal to the anterior-posterior body axis. Pairwise angles between the spermatheca, spermathecal tube and the longitudinal bridge of M. reclinata n. sp. females were measured. The angle between the spermathecal tube and longitudinal bridge is a quite stable morphometric character and thus is considered to be appropriate for comparison of different eriophyoid taxa. LTSEM and CLSM study shows that M. reclinata n. sp. possesses a unique, broadened frontal lobe of the prodorsal shield comprised of apical and basal parts entirely covering the dorsal palpcoxae. The incompletely described mite species Mackiella borasis Mohanasundaram, 1981 does not conform to the diagnosis of Mackiella and herein is transferred to the subfamily Phytoptinae incertae sedis.