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The jumping organ (furcula) is the most characteristic structure among collembolans, and it is of great taxonomical values at higher levels. The largest superfamily Entomobryoidea is traditionally classified into four families only by the morphology of the furcula. Actually, many taxa among these families are strikingly similar in morphology without considering furcula. The phylogeny of Entomobryoidea was reconstructed here based on mitochondrial and ribosomal fragments. This indicated that both Paronellidae and Cyphoderidae were ingroups within Entomobryidae with the former polyphyletic. Topology tests, which used the likelihood and Bayesian approaches, also rejected the traditional hypotheses relying on furcula morphology. Further ancestral state reconstructions have revealed that traditional taxonomical characters, i.e., furcula and body scales, had multiple independent origins in Entomobryoidea whereas tergal specialized chaetae (S-chaetae) exhibited strong phylogenetic signals. By integrating both molecular and morphological evidence, the results of this study drastically undermine the present classification of Entomobryoidea. Tergal S-chaetotaxic pattern in combination with other characters are more reasonable in taxonomy at suprageneric levels than convergent furcula. This study provides new insights of the jumping organ, which could be adaptively modified during evolution of Collembola.

Springtails (Collembola) are a group of arthropods that are found in terrestrial ecosystems throughout the world. Two species complexes, Tomocerus ocreatus and T. nigrus complexes, are widely distributed in the southern and northern parts of eastern China, respectively. There is a poor understanding of the species diversity within these complexes and of the factors affecting their diversification and dispersal. Species delimitation using a general mixed Yule coalescent model and a Bayesian multilocus approach recognized 22 DNA‐based species. This supports the presence of extensive cryptic diversity in species that are geographically widespread. In addition to genetic differences, we discovered corresponding morphological differences in jumping organs among the major clades. Analyses of divergence times and historical biogeographical processes revealed that ocreatus and nigrus complexes originated in southern and northern China, respectively. We estimated their divergence at 27.8–44.9 Mya during the Eocene–Oligocene, at the time when the transmeridional Qinling–Dabie Mountains uplifted and formed the north–south geographical boundary of eastern China. Diversification analyses suggest that the subsequent orogenesis of the Qinghai–Tibetan Plateau in western China had little impact on divergences within the two species complexes so that they maintained their geographical patterns from the Paleogene to the present day. Our findings also point to a potentially important influence of the Qinling–Dabie Mountains on patterns of animal speciation and distribution in China.

Collembola are a basal group of Hexapoda renowned for both unique morphological characters and significant ecological roles. However, a robust and plausible phylogenetic relationship between its deeply divergent lineages has yet to be achieved. We carried out a mitophylogenomic study based on a so far the most comprehensive mitochondrial genome dataset. Our data matrix contained mitogenomes of 31 species from almost all major families of all four orders, with 16 mitogenomes newly sequenced and annotated. We compared the linear arrangements of genes along mitochondria across species. Then we conducted 13 analyses each under a different combination of character coding, partitioning scheme and heterotachy models, and assessed their performance in phylogenetic inference. Several hypothetical tree topologies were also tested. Mitogenomic structure comparison revealed that most species share the same gene order of putative ancestral pancrustacean pattern, while seven species from Onychiuridae, Poduridae and Symphypleona bear different levels of gene rearrangements, indicating phylogenetic signals. Tomoceroidea was robustly recovered for the first time in the presence of all its families and subfamilies. Monophyly of Onychiuroidea was supported using unpartitioned models alleviating LBA. Paronellidae was revealed polyphyletic with two subfamilies inserted independently into Entomobryidae. Although Entomobryomorpha has not been well supported, more than half of the analyses obtained convincing topologies by placing Tomoceroidea within or near remaining Entomobryomorpha. The relationship between elongate-shaped and sphericalshaped collembolans still remained ambiguous, but Neelipleona tend to occupy the basal position in most trees. This study showed that mitochondrial genomes could provide important information for reconstructing the relationships among Collembola when suitable analytical approaches are implemented. Of all the data refining and model selecting schemes used in this study, the combination of nucleotide sequences, partitioning model and

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