Cretobrachygluta gen. nov., the first and oldest Brachyglutini in mid-Cretaceous amber from Myanmar (Coleoptera: Staphylinidae: Pselaphinae) Author Yin, Zi-Wei Laboratory of Environmental Entomology, College of Life Sciences, Shanghai Normal University, Shanghai, 200234, P. R. China Author Kurbatov, Sergey A. Museum of Entomology, All-Russian Plant Quarantine Center, Pogranichnaya 32, Bykovo 140150, Russia Author Cuccodoro, Giulio Muséum d’histoire naturelle, Case postale 6434, CH- 1211 Genève Author Cai, Chen-Yang CAS Key Laboratory of Economic Stratigraphy and Palaeogeography, Center for Excellence in Life and Paleoenvironment, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, P. R. China & School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol BS text Acta Entomologica Musei Nationalis Pragae 2019 Acta. Ent. Mus. Natl. Pragae 2019-03-04 59 1 101 106 http://dx.doi.org/10.2478/aemnp-2019-0008 journal article 5795 10.2478/aemnp-2019-0008 e3fd15a2-5823-4640-bd84-46058d760fb1 1804-6487 4505000 92E283C0-30BB-4610-8D48-12B40CF9B425 † Cretobrachygluta laurasiensis sp. nov. Type material. HOLOTYPE (SNUC-Paleo-0076): a well-preserved male in an approximately 7.2×5.0 mm clear,yellowish amber piece; upper Albian to lower Cenomanian , Hukawng Valley , northern Myanmar ( SNUC ). Diagnosis of male. As for the genus ( vide supra ), plus the following: body length 1.85 mm ; mesotrochanters protuberant at ventral margin; mesotibiae with small, triangular preapical spur. Description. Habitus ( Fig. 1 ) rather stout; total body length (combined length of head, pronotum, elytra, and abdomen) 1.85 mm . Body reddish brown, with mouthparts and tarsi paler, integument of dorsal surface densely covered with suberect fine setae. Head slightly broader than long; length from anterior margin of clypeus toward base 0.30 mm , width across eyes 0.41 mm ; eyes roundly prominent, each composed of approximately 75 facets. Length of antenna 0.86 mm ; antennomere I (scape) cylindrical, about 1.65 times as long as wide, antennomere II (pedicel) roundedcylindrical, much narrower than scape, 1.2 times as long as wide, and about 0.6 times as long as scape, antennomeres 3–7 almost moniliform, slightly elongate, antennomere 8 distinctly transverse, antennomeres 9–11 obconical, successively wider apically, antennomere 11 about twice as long as antennomere 10, truncate at base, broadest at near middle, and narrowing toward apex, with inner margin broadly emarginate in apical half (observable in Fig. 1A , right antenna). Maxillary palpi as in Figs 2 B–D; length of palpomere 1 0.03 mm , palpomere 2 0.12 mm , palpomere 3 0.06 mm , palpomere 4 0.12 mm . Pronotum slightly longer than wide, length along midline 0.41 mm , maximum width 0.37 mm ; sides roundly expanded laterally. Elytra transverse, length along suture 0.58 mm , maximum width 0.66 mm , anterior margin broadly impressed, posterior margin truncate. Legs moderately elongate, densely setose; ventral margin of mesotrochanters projecting in conspicuous process; mesotibiae bearing small, triangular preapical spur. Abdomen broadest at tergite 1 (IV), length along midline 0.66 mm , maximum width 0.57 mm ; tergites and sternites densely covered with suberect, posteriorly directed setae; tergite VIII with deep apical notch at middle of posterior margin. Fig. 2. Morphological details of † Cretobrachygluta laurasiensis gen. et sp. nov. A – left antenna; B–D – main body parts in dorsal (B), ventral (C), and lateral (D) view, with foveal pattern and other important characters annotated. Scale bar: 0.2 mm in A; 0.5 mm in B–D. Abbreviations: a1–2, 9–11 = antennomeres 1–2, 9–11; bef = basal elytral foveae; blf = basolateral fovea; dc = discal carina; gf = gular fovea; gr = gular ridge; laf = lateral antebasal fovea; lmcf = lateral mesocoxal fovea; lmsf = lateral mesoventral fovea; lmtf = lateral metaventral fovea; maf = median antebasal fovea; mmsf = median mesoventral foveae; mp4 = maxillary palpomere 4; ms = marginal stria; mtc = metacoxa; omc = ocular-mandibular carina; p = projection; plc = posterolateral cleft; s = spur; shef = subhumeral elytral fovea; sIII–VIII = sternites III–VIII; ss = sutural stria; tIV–VIII = tergites IV–VIII; tc = pretarsal claw; ts1–3 = tarsomeres 1–3; vf = vertexal fovea. Remarks. The protuberant mesotrochanters, spinose mesotibiae, and apically notched tergite VIII are interpreted as male sexual characters based on our experience in the extant brachyglutine fauna. Etymology. The specific epithet refers to the occurrence of this species on the supercontinent Laurasia some 99 million years ago. Adjective.