Molecular Correlation between Larval, Deutonymph and Adult Stages of the Water Mite Arrenurus (Micruracarus) Novus

Abstract

<jats:p>The systematics of many groups of organisms has been based on the adult stage. Morphological transformations that occur during development from the embryonic to the adult stage make it difficult (or impossible) to identify a juvenile (larval) stage in some species. Hydrachnidia (Acari, Actinotrichida, which inhabit mainly continental waters) are characterized by three main active stages—larval, deutonymph and adult—with intermediate dormant stages. Deutonymphs and adults may be identified through diagnostic morphological characters. Larvae that have not been tracked directly from a gravid female are difficult to identify to the species level. In this work, we compared the morphology of five water mite larvae and obtained the molecular sequences of that found on a pupa of the common mosquito Culex (Culex) pipiens with the sequences of 51 adults diagnosed as Arrenurus species and identified the undescribed larvae as Arrenurus (Micruracarus) novus. Further corroborating this finding, adult A. novus was found thriving in the same mosquito habitat. We established the identity of adult and deutonymph A. novus by morphology and by correlating COI and cytB sequences of the water mites at the larval, deutonymph and adult (both male and female) life stages in a particular case of ‘reverse taxonomy’. In addition, we constructed the Arrenuridae phylogeny based on mitochondrial DNA, which supports the idea that three Arrenurus subgenera are 'natural': Arrenurus, Megaluracarus and Micruracarus, and the somewhat arbitrary distinction of the species assigned to the subgenus Truncaturus.</jats:p>

Species boundaries among extremely diverse and sexually dimorphicArrenuruswater mites (Acariformes: Hydrachnidiae: Arrenuridae)

“…To date, there are very few studies targeting certain aspects of taxonomical assesments of Arrenurus , where the validity of morphospecies is tested with the application of molecular markers (e.g. Blattner et al, 2019; Alarcón-Elbal et al, 2020). However, in the recent published article of Alarcón-Elbal et al (2020) phylogenetic relationships among Arrenurus species were missinterpreted.…”

“…Blattner et al, 2019; Alarcón-Elbal et al, 2020). However, in the recent published article of Alarcón-Elbal et al (2020) phylogenetic relationships among Arrenurus species were missinterpreted. Whereas the authors stated that subgenera Arrenurus, Megaluracarus and Micruracarus are “natural” and only subgenus Truncaturus is an arbitrary assemblage of species, in fact non of the examined by the authors subgenera is monophyletic when interpreting results of the phylogenetic tree presented by the authors (Alarcón-Elbal et al, 2020).…”

Species boundaries among extremely diverse and sexually dimorphic Arrenurus water mites (Acariformes: Hydrachnidia: Arrenuridae)

“…Further studies with more genes are needed. To date, there are very few studies targeting certain aspects of taxonomical assessments of Arrenurus, where the validity of morphospecies is tested with the application of molecular markers (e.g Blattner et al 2019;Alarcón-Elbal et al 2020;Montes-Ortiz et al 2022)…”

“…. However, in the article ofAlarcón-Elbal et al (2020) phylogenetic relationships among Arrenurus species were missinterpreted. Whereas the authors stated that subgenera Arrenurus, Megaluracarus and Micruracarus are "natural" and only the subgenus Truncaturus is an arbitrary assemblage of species, in fact none of the subgenera examined by the authors is monophyletic when interpreting results of the phylogenetic tree they present (Fig.12,Alarcón-Elbal et al 2020).…”

Molecular Phylogenetics and Mitochondrial Evolution

“…Different strains of the cattle protozoan parasite Theileria parva are identified using mitochondrial single nucleotide polymorphisms in the work by Mwamuye and colleagues [11]; the population structure of the endangered freshwater mussel Unio crassus from Eastern Europe is unraveled by Kilikowska and colleagues [12] using one nuclear and two mitochondrial markers; similarly, the population genetics of the Portuguese oyster Crassostrea angulata is addressed by Chiesa and colleagues [13]. Conversely, Alarcón-Elbal and colleagues [14] provide a high-quality example of tracking the complete life cycle the water mite Arrenurus (Micruracarus) novus by means of morphology interwoven with the sequence of mitochondrial genes cox1 and cytb at different life stages.…”