A review of Nearctic Lathrobium (Coleoptera, Staphylinidae), with revision and descriptions of new flightless species from the mountains of the southeastern U. S. Author Haberski, Adam https://orcid.org/0000-0002-4062-178X Department of Plant & Environmental Sciences, Clemson University, Clemson, SC 29634 - 0310, USA ahaberski@gmail.com Author Caterino, Michael S. https://orcid.org/0000-0002-2597-5707 Department of Plant & Environmental Sciences, Clemson University, Clemson, SC 29634 - 0310, USA text ZooKeys 2024 2024-04-25 1198 193 277 http://dx.doi.org/10.3897/zookeys.1198.118355 journal article http://dx.doi.org/10.3897/zookeys.1198.118355 1313-2970-1198-193 59053839702C46C9B0F6AA37C61C0E45 0257BC4776C25532B6CEB2BDECD8E7AB Lathrobium (Lathrobium) amplipenne Casey, 1905 Lathrobium amplipenne Casey, 1905: 81. Type material. Lectotype , Lathrobium amplipenne Casey, herein designated (USNM): "N. Y. / CASEY bequest 1925 / [red] TYPE USNM 38107 / [handwritten] Lathrobium amplipenne / Lectotype Lathrobium amplipenne Casey Desg. Haberski & Caterino." Other material. Illinois: Union Co., 1 mi E Wolf Lake, 8.V.1976 , A. Smetana (2, CNC); 2 mi NE Reynoldsville, 9.V.1976 , A. Smetana (1, CNC). Indiana: Tippecanoe Co., 27.X.1956 , N.M. Downie (1, CNC). Louisiana: Concordia Pa. [Park?], 5 mi W Ferriday, 1.V.1976 , A. Smetana (1, CNC). Missouri: St. Louis Co., 9.V.1920 , G.W. Bock (1, CNC). New York: Tompkins Co.: Ithaca Valley, (9, USNM). Pennsylvania: 'Penn.' . F. C. Bowditch (1, MCZ). South Carolina: Charleston Co.: Ravenel, 05 May 2001 , J. C. Ciegler, UV light (2, CUAC); Dorchester Co.: Bluff Trail, McAlheny Nature Preserve, Reevesville, 11 May 2013 , J. C. Ciegler (1, CUAC); Marion Co.: Woodbury, 10 Sep 2011 , J. C. Ciegler (1, CUAC). Diagnosis. The habitus of this species closely resembles that of L. armatum , L. geminum , L. praelongum , and L. pedale . Males differ from those species in their unique sternite VIII, which has three small emarginations at the apex and two longitudinal patches of dense setae (Fig. 34B ). Females are difficult to tell apart from L. armatum and L. praelongum . Their paraprocts are slightly shorter than those of L. armatum , and longer than those of L. amplipenne , relative to the basal portion of tergite IX. Females can be easily distinguished from L. geminum , which has gonocoxites shorter than paraprocts, and L. pedale , which has valvifers and coxites divided. Description. Large species, body length 10 mm; body coloration dark, appendages lighter red, elytra bicolored. Gular sutures converging, nearly touching posteriorly; antennomeres V-VII longer than wide. Elytra 1.3 x as long as pronotum. Females with paraprocts undivided, apices shorter than basal portion; sternite VIII conical with shallow notch at tip. Male sternite VIII with three emarginations (Fig. 34B ). Genitalia as in Fig. 34 . The length of the ventral process of the aedeagus can vary. Distribution. Canada: ON, NB, QC ( Bousquet et al. 2013 ). USA; IL , IN , LA , MI, MO , NY, PA , SC.