Throscidae (Coleoptera) relationships, with descriptions of new fossil genera and species Author Muona, Jyrki text Zootaxa 2019 2019-04-03 4576 3 521 543 journal article 10.11646/zootaxa.4576.3.6 7abdc62c-c350-49dd-8060-4ed64da07362 1175-5326 3715772 56BC8573-D4A1-4B18-9BF6-7AB5F7984BFD Tyrannothroscus new genus Type species : Tyrannothroscus rex new species Diagnosis . Elateroidea synapomorphy: pro-mesothoracic joint with clicking mechanism. Throscidae synapomorphies: a2 as wide as a3–a4, antennal grooves running along notosternal suture and then bending laterally along proleg cavity ( Fig. 6 ). Synapomorphies of Rhomboaspis + Tyrannothroscus + Potergini + Throscini : antennal grooves and proleg impressions separated by septum, metaventrite with tarsal grooves, abdomen with tarsal grooves. Synapomorphies of Rhomboaspis + Tyrannothroscus : elytra with strong and sharp, at most minutely punctate striae, body form very wide. Tyrannothroscus apomorphies: head with strong carinae above antennal insertions ( Fig. 7 ), metasternal discrimen well developed, meso- and metatarsomeres 4 lobed beneath ( Fig. 8 ). Diagnostic other characters: pronotal lateral carinae complete, head without median carina, antennal insertions located in fossae, antennae with apical, symmetrical club, prosternal process basally straight in lateral view. Description . Body wide, flattened, pronotum strongly narrowing anteriorly ( Figs. 6 , 9 ). Head with strong supraocular ridges uniting in mid-line, frontoclypeus narrow, elongate, eyes large, antennae stout, a1 wide and short, a2 shorter than a3 and a4 but as wide, a9–a11 forming a club. Clypeus well slerotized, small. Anterior edge of prosternum strongly developed, projecting downwards as a wide arched extension. Metaventrite large and wide, cavity for pro- and mesolegs well-developed, ridged around and with separate sections for both legs, proleg area exceptionally wide, metatarsal grooves long, lateroposteriorly directed ( Fig. 6 ). Prosternal process slightly narrowed in middle, diverging strongly posteriorly, lateral carniae complete and apex rounded ( Figs. 1 , 6 ). Metacoxae with prominent median apex, abdominal tarsal grooves extending to ventrite four. Elytral striae sharp, interstices flat, wide. Tibiae simple, without tarsal grooves, tarsi delicate, t4 lobed below. Etymology . Tyrannothroscus refers to the relatively large size of this throscid, the largest known.