First extinct representative of the rove beetle subtribe Acylophorina from Baltic amber, and its phylogenetic placement

The recently established subtribe Acylophorina comprises several morphologically diverse genera. They were revealed as a monophyletic group primarily by molecular-based phylogenetic analysis. The morphological disparity and significantly disjunct geographical distribution of Acylophorina suggest a higher diversity in the past that has been reduced by extinctions. Consequently, the fossil record preserving extinct transitional morphologies is a very important source of data to test for monophyly and improve overall phylogenetic understanding of this subtribe. Here, we describe the first undoubted representative of the subtribe as a new species, <i>Acylophorus hoffeinsorum</i> sp. nov., and confirm its placement within Acylophorina by phylogenetic analysis using Bayesian inference and maximum parsimony methods. We question the monophyly of <i>Acylophorus</i> Nordmann, 1837, the most speciose genus in the subtribe, and call for further phylogenetic investigation and taxonomic revision of this genus and the subtribe as a whole. Additionally, we argue that the extinct Cenozoic <i>Acylophorus immotus</i> Scudder, 1900, which so far has been erroneously known as the only fossil member of Acylophorina, in fact belongs to the subfamily Tachyporinae. http://zoobank.org/urn:lsid:zoobank.org:pub:D14B76FC-E0E5-4BC6-BDCE-3D577891C55D

新近建立的Acylophorina亚族（Acylophorina）包含多个形态多样的属。该类群经基于分子的系统发育分析证实为单系群。Acylophorina亚族的形态分异度与显著的间断地理分布表明，其过往曾具有更高的多样性，后因灭绝事件而大幅锐减。因此，保存有已灭绝过渡形态的化石记录，是检验该亚族单系性、深化对其整体系统发育认知的极为重要的数据来源。本文记述了该亚族首个确凿的代表类群——新种*Acylophorus hoffeinsorum* sp. nov.，并通过贝叶斯推断与最大简约法开展系统发育分析，确认其隶属于Acylophorina亚族。我们对该亚族中物种最为丰富的属——*Acylophorus* Nordmann, 1837的单系性提出质疑，并呼吁针对该属及整个亚族开展进一步的系统发育研究与分类修订。此外，我们提出，此前被误认作Acylophorina亚族唯一化石成员的新生代已灭绝物种*Acylophorus immotus* Scudder, 1900，实则隶属于苔隐翅虫亚科（Tachyporinae）。相关LSID标识链接：http://zoobank.org/urn:lsid:zoobank.org:pub:D14B76FC-E0E5-4BC6-BDCE-3D577891C55D