Bothronotoxenus Eldredge, A New Genus Of Aleocharinae (Coleoptera: Staphylinidae) From Arizona, U. S. A. Author Eldredge, K. Taro Department of Ecology and Evolutionary Biology, and Division of Entomology Biodiversity Institute, 1501 Crestline Dr., Suite 140 University of Kansas, Lawrence, KS 66045 - 2811, U. S. A. taroeldredge@ku.edu text The Coleopterists Bulletin 2011 2011-12-01 65 4 381 386 journal article 10.1649/072.065.0413 1938-4394 10085419 Bothronotoxenus Eldredge , new genus Diagnosis. Bothronotoxenus and its only species, B. tishechkini , can be separated from all other Lomechusini by its unique pronotum with a bisinuate anterior margin and a pair of deep, circular depressions on the disk just posterior of the sinuations. Description. Integument without microsculpture; tarsal formula 4-5-5; antennae 11-segmented. Head ( Figs. 1–2 ): Transverse (HW = 0.57 mm , HL = 0.42 mm , HW/HL = 1.36) and widest behind eyes; temples swollen posteriorly and extending beyond occipital foramen; occipital and frontal suture absent; neck absent. Antennae compact with antennomeres IV-XI parallel-sided and pedicels scarcely visible. Labrum transverse. Mandibles with apex inwardly recurved, surpassing basointerior articulation. Maxilla ( Fig. 5 ) with cardo ventrally overlapping base of stipes; galea long and consisting of distal lobe with abundant setae; lacinia with several teeth on apex and margin partially delimited by medial dilation, overall accompanied by several layers of setae; palpi 4-segmented, palpomere IV with filamentous sensillae. Labium ( Fig. 3 ) with 3-segmented palpi; palpomeres I and III subequal in length, palpomere II shorter with membranous zone; glossa divided to near base with single terminal sensillate element on each lobe. Mentum ( Fig. 6 ) transverse and trapeziform, with apical margin broadly and shallowly arcuate, posterior-most extension at rounded basolateral angles. Pronotum ( Figs. 1–2 ): Transverse (PW = 0.72 mm , PL = 0.42, PW/PL = 1.71), shape cordiform with anterior margin bisinuate and posterior margin evenly arcuate without posterolateral angles, disk with circular impressions just behind anterior sinuations, marginal bead present and complete, hypomeron fully visible in lateral view. Mesocoxae set in cavities with complete marginal bead, moderately separated by long metaventral and mesoventral process that barely extends between coxae, isthmus short. Elytra ( Fig. 1 ) transverse (EW = 0.78, EL = 0.57, EW/EL = 1.37), laterodistal angles weakly produced but not sinuate. Hind wings fully developed. Abdomen ( Figs. 1–2 ): Widest at base and slightly tapering towards apex, macrosetae inconspicuous and secondary setae extremely long and fine. Tergite VII with transverse defensive gland opening, occupying little less than half width of segment at base. Type species. Bothronotoxenus tishechkini , new species . Etymology. The generic name is derived from Greek to mean guest with pits on its back. Its gender is masculine.