Thinobius procerus Eppelsheim, 1859

(Figs 3, 8–10, 15, 25–26, 28, 43)

Thinobius (Thinophilus) procerus Eppelsheim, 1893: 63.

Trogophloeus teres Fall, 1926: 146., syn. n.

Examined type material – Thinobius (Thinophilus) procerus Eppelsheim – Holotype (♂): “ ♂ \ Ost-Sibirien.; Quellgebiet; des Irkut.; Leder 1891. \ procerus; Epp. \ procerus; Epp. Deutsch. ent.; Zeit. 1893. p. 63. \ c. Epplsh.; Steind. d. \ Typus \ Holotypus; Thinobius; procerus Eppelsheim; ver. Makranczy, 2013 \ Thinobius; procerus Eppelsheim; det. Makranczy, 2013” (NHMW); Trogophloeus teres Fall – Holotype (♀): “ McKin.[ley] P[ar]k [Station]; Alaska; 7[=VII.]-9-[19]24. \ Type; teres \ M.C.Z.; Type; 24055 \ H.C. Fall; Collection \ Holotypus; Trogophloeus; teres Fall; ver. Makranczy, 2000 \ Thinobius; procerus Eppelsheim; det. Makranczy, 2013” (MCZN).

Other material – RUSSIA: “♂ \ Baikal; Bang- Haas \ procerus Epp., vgl. m. Type; determ. Bernh \ Gezeichnet!; 7.IV.1942; O. Scheerpeltz \ procerus Eppelsh.; det. O. Scheerpeltz, 1942 \ Dr. M. Bernhauer; 10.XI. donavit 1942 \ ex coll.; Scheerpeltz” (2 ♂, NHMW); N-Cisbaikalia, Buryatia, Baikal Mts, Kurkula riv., [Peshekhodnyi stream,] 55°05’52.0[46.1]’’N, 108°55’33.9’’E, 725 m, 1–2.VII.2013, leg. I. V. Enushchenko (1 ♂, coll. Shavrin, 1 ♀, MHNG); N-Cisbaikalia, Buryatia, Baikal Mts., left side of Kurkula riv., [Vodopadnyi stream,] 55°05’52.0’’N, 108°47’06.5’’E, 981 m, 7–8.VII.2013, leg. I. V. Enushchenko (3 ♂, 1 ♀, HNHM, 1 ♀, NHMW); E-Siberia, KhamarDaban Mts, Komarinskiy Mts., middle flow of Slyudyanka Riv., 51.587736°N, 103.630056°E, 14–15.VII.2013, leg. A. V. Shavrin & I. V. Enushchenko (5 ♂, 2 ♀, coll. Shavrin, 1 ♂, MHNG, 4 ♀ HNHM); Transbaikalia, Chita Area, Kyrinskiy District, Bal’dzha Riv., 49°17’54.4”N, 110°09’20.8”E, 1432 m, 5.VIII.2013, leg. I. V. Enushchenko (2 ♀, coll. Shavrin, 1 ♂, HNHM); Siberia or., Chabarowskij kr., Badshalskij Geb., Mündg. des Omot-Makit [approx. 50°34’23”N, 134°19’42”E], 850 m, 12.VII.1997, leg. J. Sundukow (S31) (1 ♂ 3 ♀, coll. Schülke); Primorie, Schutzgebiet Lazowkij Kl. S-j. Log [approx. 43°12’N, 133°47’E], 5.VI.1997, leg. J. Sundukow (S32) (1 ♀, coll. Schülke); USA /ALASKA: Kenai Mts., Tern Lake Campground, 700’, 12.VI.1978, leg. A. Smetana & E. C. Becker (1 ♂, CNCI, 1 ♂, HNHM); 12mi N mi78 Denali Hwy, Windy Creek, 13.VII.1978, leg. A. Smetana (1 ♂, CNCI); mi220 George Parks Hwy, 14.VII.1978, leg. A. Smetana (2 ♂, CNCI); Prudhoe Bay Rd., 9mi N Atigun Pass, 68°14’N, 149°25’W, 3100’, 6.VII.1978, leg. J. M. Campbell & A. Smetana (1 ♂, 1 ♀, CNCI).

Redescription – Measurements (in mm, n = 10): HW = 0.35 (0.33–0.37); TW = 0.35 (0.32–0.37); PW = 0.40 (0.38–0.42); SW = 0.47 (0.43–0.50); AW = 0.51 (0.48–0.55); HL = 0.31 (0.29–0.33); EL = 0.10 (0.10–0.105); TL = 0.10 (0.095 –0.105); PL = 0.31 (0.30–0.33); SL = 0.61 (0.57–0.65); SC = 0.54 (0.51–0.57); FB = 1.26 (1.21–1.30); BL = 2.43 (2.12–2.77). Body (Fig. 3) slightly to barely bicoloured. Head, pronotum and abdomen dark brown, occasionally with slight reddish tint, elytra reddish medium brown with a darker, blackish area behind scutellum extending to shoulders. Legs, mouthparts and antennae slightly reddish medium to dark brown, only tibiae and tarsi somewhat lighter. All main body parts with very fine coriaceous microsculpture intermixed with very fine and rather dense punctation, making body moderately lustrous. Punctation on head (especially middle of vertex) stronger, moderately deep, pronotum slightly less strong and more dense, elytra even finer and denser, on abdomen more indistinct; on tergite VII both coriaceous microsculpture and punctation fading posteriorly (as also on mostly unexposed tergite VIII), making tip of abdomen much shinier than rest. Pubescence on forebody rather depressed, short, fine and dense (on elytra the most dense), on abdomen somewhat less dense but not longer hairs, apices of tergites with a row of conspicuously long hairs, abdominal sides and apex with a few darker and stronger bristles. Strong dark bristle on outer side of supraantennal tubercle at anterior border of eye and on posterior edge of vertex adjacent to temples, similar ones right behind anterior pronotal corner and on side at 3/5 length. Direction of setation on edges of head (especially at supraantennal tubercles) postero-lateral, on most of vertex medial except anteriad neck groove where rather mixed. Pronotal setation mostly medially directed, but on middle of disc turning slightly antero-medial, posterior half of middle of disc disctinctly antero-medial, posterior pronotal edge mostly anterior. Elytra and abdomen with posteriorly directed hairs. Antennae, legs and mouthparts with very short, not conspicuous setation, except for the stiff, darker hair slightly distal from middle of each tibia and ones near apices of femora. Elytra with the regular stiffer lateral setae inconspicuous, practically mixed in with other setae on side.

Head slightly wider than long, temples usually straight, with a gentle curve on the side, rounded on posterior part. Middle of vertex very gently impressed. Anterior border of neck not marked with groove, only by change of microsculpture. Frontoclypeal suture appearing as fine, often shinier groove and dark line (visible only if head lighter) connecting supraantennal tubercles, similarly darker spots situated at both sides on middle of vertex. Supraantennal tubercles moderately developed, weakly separated from vertex. Antennae somewhat elongate (Fig. 15), 6th antennomere appearing smaller than adjacent ones.

Pronotum weakly transverse, 1.30× wider than long, just a little wider than head, pronotum with only traces of impressions at sides of unmarked midline and posterior margin. Anterior corners rather weakly rounded, posterior corners very broadly, sides gently arched. Pronotal marginal bead visible on posterior margin, anterior margin only gently arched (almost straight) with traces of a marginal bead in middle. Scutellum large, setose and dull. Elytra quite long, one elytron a little bit more than twice as long as broad, quite flat and parallel-sided (very gently dilating posteriorly). Shoulders moderately developed. Along suture with fully developed but thin marginal bead, mostly at broadly rounded sutural corners. Legs of medium length, tarsal lobes broader at base but thin at apex, tibiae moderately fusiform, appear much wider in middle than at ends.

Abdomen (Fig. 8) very weakly fusiform, sides more or less straight and parallel; widest in the middle, just very slightly less wide than elytra at broadest point. Posterior margin of tergite VII with light coloured and distinct palisade fringe.

Primary and secondary sexual features – Males immediately recognizable by a variously developed but always conspicuous, posteriorly directed tooth on hind femur (Fig. 10). Sexes not appearing different in regular dorsal view. Posterior corners of tergite VIII (similar in both sexes) gently pulled out, posterior edge otherwise straight. Male sternite VIII as in Fig. 28, tergite IX as in Fig. 25, sternite IX as in Fig. 26. Aedeagus as in Fig. 43.

Distribution – The species is known from the northern areas of both the Eastern Palaearctic and the Western Nearctic regions.

Remarks – The spermathecae in all the preceding taxa are extremely weakly sclerotized, to such an extent that they are often difficult to observe. They are of a simple boomerang shape, roughly equal breadth on the whole length; this offers very little in terms of diagnosis, therefore only one specimen is illustrated here, the neotype of Thinobius angusticeps Fauvel.