Integrative Taxonomy of the Gall Mite <i>Nothopoda todeica</i> n. sp. (Eriophyidae) from the Disjunct Afro-Australasian Fern <i>Todea barbara</i>: 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 todeica n. 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. todeica n. 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

A New Webbing <i>Aberoptus</i> Species from South Africa Provides Insight in Silk Production in Gall Mites (Eriophyoidea)

Arthropods include a high diversity of lineages adapted for silk production. Several species of microscopic phytophagous mites of the hyperdiverse superfamily Eriophyoidea spin web; however, the origin of their silk is unknown. We described a new web-spinning mite, Aberoptus schotiae n. sp., collected from leaves of Schotia brachypetala (Fabaceae) in South Africa and showed that it has a complex life cycle, including two morphotypes of adults and nymphs. Molecular phylogenetic analyses and 28S sequence comparison showed conspecificity of heteromorphic females and rejected synonymy of Aberoptus and Aceria proposed by previous authors. For the first time, we provided SEM images of the web nests and, using a set of different microscopic techniques, described the silk-producing anal secretory apparatus (ASA) of Aberoptus. It comprises two pairs of anal glands (hypertrophied in web-spinning females), three cuticular sacs and a rectal tube leading to the anal opening. This is a unique case (analogy) of anal silk secretion in Chelicerata previously reported only in Serianus (Pseudoscorpiones). Recent findings of rudimentary ASA in distant eriophyoid lineages and the results of this study transform the current paradigm of exoticism of web-spinning eriophyoid taxa into the concept of synapomorphic specialization of the hindgut for excreting the anal gland secretions in Eriophyoidea

A New Webbing Aberoptus Species from South Africa Provides Insight in Silk Production in Gall Mites (Eriophyoidea)

Arthropods include a high diversity of lineages adapted for silk production. Several species of microscopic phytophagous mites of the hyperdiverse superfamily Eriophyoidea spin web; however, the origin of their silk is unknown. We described a new web-spinning mite, Aberoptus schotiae&nbsp;n. sp., collected from leaves of Schotia brachypetala (Fabaceae) in South Africa and showed that it has a complex life cycle, including two morphotypes of adults and nymphs. Molecular phylogenetic analyses and 28S sequence comparison showed conspecificity of heteromorphic females and rejected synonymy of Aberoptus and Aceria proposed by previous authors. For the first time, we provided SEM images of the web nests and, using a set of different microscopic techniques, described the silk-producing anal secretory apparatus (ASA) of Aberoptus. It comprises two pairs of anal glands (hypertrophied in web-spinning females), three cuticular sacs and a rectal tube leading to the anal opening. This is a unique case (analogy) of anal silk secretion in Chelicerata previously reported only in Serianus (Pseudoscorpiones). Recent findings of rudimentary ASA in distant eriophyoid lineages and the results of this study transform the current paradigm of exoticism of web-spinning eriophyoid taxa into the concept of synapomorphic specialization of the hindgut for excreting the anal gland secretions in Eriophyoidea

Atypically Shaped Setae in Gall Mites (Acariformes, Eriophyoidea) and Mitogenomics of the Genus <i>Leipothrix</i> 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 juniperensis n. 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

Molecular Phylogenetics and Light Microscopy Reveal “True” and “False” Calacarines and Novel Genital Structures in Gall Mites (Acariformes, Eriophyoidea)

Gall mites (Eriophyoidea) are cosmopolitan microscopic phytoparasites that often transmit viruses and induce gallogenesis. The tribe Calacarini is diagnosed by a set of plesiomorphic and homoplastic traits, including elimination of setae sc shared with other lineages of Eriophyoidea. We reviewed data on the generic diversity of calacarines, revised the concept of the type genus Calacarus Keifer 1940, and proposed three zones (MZ, SMZ, LZ) in the prodorsal shields of calacarines to simplify descriptions of their shield patterns. We describe three new calacarine species (Calacarus baviensisn. sp., C. burchelliaen. sp., and Viginticus searsiaen. sp.) from indigenous dicotyledonous trees from South Africa and Vietnam and report on new findings of Paracalacarus podocarpi Keifer in Brazil, Jiangsuacarus sp. in the USA, and Calacarus pusillus Pye in Latvia and Russia. The latter represents the new most northern locality of Calacarini. Reinvestigating the type species of Jaranasia Chandrapatya & Boczek 2000 revealed that absence of setae l’’ II is the only character separating it from Jiangsuacarus Xue 2009. We proposed two new combinations: Jiangsuacarus sesleriae (Skoracka 2004) n. comb. (transferred from Jaranasia) and Procalacarus mussaendae (Keifer 1977) n. comb. (transferred from Calacarus). Partial sequences of Cox1 and 28S genes were obtained for six calacarines, some of them originating from old ethanol material kept at room temperature. Molecular phylogenetics revealed a stable cluster of “true” calacarine sequences comprising Calacarus, Jaranasia, Latitudo, and Viginticus and a polyphyletic group of erroneous sequences assigned to Calacarini in GenBank. All investigated females of calacarines have a pair of genital tubules associated with the vestibulum and hypothesized to participate in fertilization. This finding may contribute to resolving the question on how the fusion of gametes happens in gall mites