Morphological support for a clade comprising two vermiform mite lineages: Eriophyoidea (Acariformes) and Nematalycidae (Acariformes)

A morphology-based parsimony analysis (50 taxa; 110 characters) focused on relationships among basal acariform mites places Eriophyoidea (formerly in Trombidiformes) within Nematalycidae (Sarcoptiformes). Although both taxa have worm-like bodies, this grouping is unexpected because it combines obligate plant inhabitants (Eriophyoidea) with obligate inhabitants of deep-soil or mineral regolith (Nematalycidae sensu stricto). The Eriophyoidea + Nematalycidae clade, which is strongly supported (Bremer =5; bootstrap =85%), retains moderately good support (Bremer=3; bootstrap=66%) when three ratio-based characters pertaining to body shape are excluded. A total of eleven unambiguous synapomorphies unite all or some of Nematalycidae with Eriophyoidea. These include an annulated opisthosoma, an unpaired vi seta on the prodorsum, fusion of the palp trochanter with the palp femur, and a large relative distance between the anus and the genitalia. Three of the four Triassic genera of eriophyoid-like...

一项基于形态学的简约性分析（morphology-based parsimony analysis）共纳入50个分类单元（taxa）与110个性状（characters），聚焦基干螨形螨类（basal acariform mites）的系统发育关系，研究结果将瘿螨总科（Eriophyoidea，原隶属于绒螨目Trombidiformes）归入线螨科（Nematalycidae，疥螨目Sarcoptiformes）。尽管两类群均具有蠕虫状躯体，但该分组结果出人意料：它将专性营植物寄生的瘿螨总科，与严格仅栖息于深层土壤或矿物风化层的狭义线螨科（Nematalycidae sensu stricto）合并为一支。瘿螨总科+线螨科分支得到了极强支持（Bremer支持度（Bremer support）=5；自举支持率（bootstrap）=85%）；当剔除3个与躯体形状相关的比例型性状后，该分支仍保留中等支持度（Bremer支持度=3；自举支持率=66%）。总计有11项明确的共有衍征（synapomorphies）将线螨科全部或部分类群与瘿螨总科关联起来，包括具环纹的后体部（annulated opisthosoma）、前足体上单根vi毛、须肢转节（palp trochanter）与须肢股节（palp femur）愈合，以及肛门与生殖孔间相对间距较大。目前已发现的4个类瘿螨类三叠纪属（Triassic genera）中，有3个...