The past and the present through phylogenetic analysis: the rove beetle tribe Othiini now and 99 Ma
Kypke, J.L., Solodovnikov, A., Brunke, A., Yamamoto, S., Żyła, D. (2019). The past and the present through phylogenetic analysis: the rove beetle tribe Othiini now and 99 Ma. Systematic Entomology, [online] 44(1), 1-18. http://dx.doi.org/10.1111/syen.12305
Plain language summary
The rove beetle subfamilies Staphylininae and Paederinae are two closely related, diverse, and entirely predaceous lineages that are diverse globally. They have been classified as these two groups since historical times, yet are not well defined. Thus, their classification may be inadequate. A recent surge in the discovery of exciting 100 MY old amber fossils has allowed systematists to re-examine evolutionary hypotheses about a wide range of beetles. The fossil taxa are often challenging to identify because they represent intermediate forms between different groups and their morphology often brings critical insight into phylogeny. A series of a new fossil genus was discovered and described by an international team of authors, which appeared to be intermediate between subfamilies Staphylininae and Paederinae. The authors conducted a phylogenetic analysis of morphological data, including these fossils. The results confirmed recent doubts from molecular data about the validity of a two-subfamily system. This new dataset and conclusions, combined with the existing molecular data, will form the basis for a wider re-examination of rove beetle higher classification.
In order to classify and taxonomically describe the first two fossil Othiini (Coleoptera: Staphylinidae: Staphylininae) species from three well-preserved specimens in Cretaceous Burmese amber, a phylogenetic analysis was conducted, combining extant and extinct taxa. A dataset of 76 morphological characters scored for 33 recent species across the subfamilies Staphylininae and Paederinae was analysed using maximum parsimony and Bayesian inference methods. The many differing phylogenetic hypotheses for higher-level relationships in the large rove beetle subfamilies Staphylininae and Paederinae were summarized and their hitherto known fossil record was reviewed. Based on the analyses, the new extinct genus Vetatrecus gen.n. is described with two new species: V. adelfiae sp.n. and V. secretum sp.n. Both species share character states that easily distinguish them from all recent Othiini and demonstrate a missing morphological link between subfamilies Staphylininae and Paederinae. This is the first morphology-based evidence for the paraphyly of Staphylininae with respect to Paederinae, suggested earlier by two independent molecular-based phylogenies of recent taxa. Our newly discovered stem lineage of Othiini stresses the importance of fossils in phylogenetic analyses conducted with the aim of improving the natural classification of extant species. It also suggests that the definitions of Staphylininae and Paederinae, long-established family-group taxa, may have to be reconsidered. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:817F39C4-F36B-4FD9-96CD-5F8F....