Stenaptinus dissolutus ( Andrewes, 1923 )

Fedorenko, D. N., 2020, Stenaptinus (Coleoptera: Carabidae: Brachininae) of Vietnam. Note 1, Russian Entomological Journal 29 (4), pp. 361-376 : 369-371

Stenaptinus dissolutus ( Andrewes, 1923) , stat.rest.

Figs 7, 10 , 22, 25 , 37, 40 , 50–51 , 55, 59 , 70 .

Andrewes, 1923: 221 ( Pheropsophus scythropus var.; Laos); 1930: 276; Csiki, 1932: 1597. — scythropus (part.): Lorenz, 1998: 15; 2005: 15; Hrdlička, 2003: 218; 2017b: 480. — ssp. kalyakini Fedorenko, 2013: 279 ( Pheropsophus ; Central Vietnam), stat.n.

MATERIAL. 14 specimens ( SIEE) from northern Vietnam, including 2♀♀, Phu Tho Province, ~ 90 km W of Hanoi, Xuan Son National Park, 21°07´52´´ N / 104°57´07´´ E, h= 400–470 m, 6– 15.VI.2014, D. Fedorenko leg.; 2♂♂, 2♀♀, same data, except for 21°08´12´´N / 104°57´04´´E, h= 450 m, 27.VI–7.VII.2014, A. Abramov & A. Shchinov leg.; ♀, Son La Province, Moc Chau, 15.V.1991, Joint Russia-Vietnam Tropical Center; 2♂♂, 2♀♀, Nghe An Province, Que Phong District, Pu Hoat National Park , 19°45´42´´N / 104°47´28´´E, h= 1130 m 15–27.V.2019, leg. D. Fedorenko; 2♀♀, same data, except for 19°45´N / 104°46´38´´E,h= 1220m; ♀, same data,except for 19°46´12´´N / 104°48´16´´E, h= 1340 m. — Holotype ♂ ( ZMMU) and 8 paratypes ( SIEE) of S. kalyakini , including 4♂♂, 3♀♀ labelled: ‘Central Vietnam, Ha Tinh Prov[ince]., Vu Quang (Phu Quon) [Nature] reserve, h~ 1.200 m, 5–26.VIII.1997, leg. M. Kaliakin’; and ♀ with same data label, except for h~ 400–700 m, 27.VIII—4.X.1997.

Additional material ( SIEE, MPSU): 4♂♂, 3♀♀, China, Southern Sichuan, env. Xichang , h= 1600 m, 21.V.2018, leg. A. Gorodinski ; ♂ ♀, same data except 18.VII.2001 .

Aedeagus examined in eight males, four from Vietnam and four from China.

REDESCRIPTION. BL 12.6–14.9 mm. Body ( Fig. 70 ) a little shiny, dorsally brown to (mostly) black; supra-antennal plates, mouthparts, legs and antennae reddish yellow; femoral apices slightly to indistinctly infuscated on sides. Head black, with labrum pale laterally, to reddish in front of eyes, with pale colour medially reaching mid-eye level; this pale pattern mostly infuscated, so that two cloudy median patches are only traceable, subtransverse clypeal and small frontal at mid-eye level. Ventral side dark coloured along sides, reddish medially. Abdominal sternites each dark brown apically and laterally, mostly deep red to reddish-brown in basal two thirds. Head ventrally red to brown black, with gula pale.

Head and pronotum with fairly coarse isodiametric microsculpture; elytral microsculpture distinct, consisting of longitudinal meshes along ridges and of coarse and very longitudinal meshes in between, being hardly traceable in specimens with very dense carinulate sculpture.

Dorsum subglabrous, head laterally with sparse or very sparse setigerous punctures, a few just behind and up to seven before supra-ocular seta; genae sparsely to moderately pilose below and just behind eyes. Pronotum rather sparsely pilose and punctate along sides (mostly in basal two thirds) and in apical third or along apex only, sometimes almost glabrous. Elytra sparsely pilose along sides and at apices, otherwise with very few short setae here and there in addition to sparse and nearly indistinct microscopic ciliae. Venter densely pilose, propleura very sparsely pilose in apical third, notopleura glabrous.

Head rather smooth medially, with sparse microscopic punctures, finely striated to rugulose along sides of frons to vertex, coarselyrugoseacrossneck.Eyesmedium-sized,convexorslightly flattened, genae very smoothly extended into neck, nearly indistinct to fairly long. Frons in lateral view slightly convex to slightly concave, frontal foveae in form of wide and shallow grooves, slightly deeper to somewhat pit-like just behind frontoclypeal suture, slightly converging basad and not quite reaching mid-eye level, extended onto clypeus into rather deep and wide grooves diverging and disappearing outside or adjoining, or almost reaching clypeal seta. Clypeus more or less sinuate apically. Labrum apically truncate to convex, with widely rounded angles.

Pronotum cordate, barely longer than wide, as wide as head, broadest a fourth from apex. Base as wide as apex, basal margin barely concave to truncate, or barely convex medially, apical margin barely or slightly concave. Sides finely beaded, evenly S-shaped, rounded in apical half, sinuate in front of and diverging toward basal angles; these slightly acute to nearly right, mostly rather sharp, not seldom distinctly acute due to apices projecting slightly basad or laterobasad. Transverse impressions vague, basal straight, apical V-shaped, median line fine between them, otherwise obliterate. Basal foveae vague, running more or less parallel to lateral margin in basal half or almost reaching apex.

Elytral ridges fine, those 2 to 5 often wider, slightly to indistinctly broadened basally, 8th slightly shortened apically and often also basally, 6th obliterate, sometimes hardly traceable, in basal 1/7–2/5 (mostly 1/4–1/5). Chetotaxy as for S. montanus .

Abdomen ( Figs 7, 10 , 22, 25 ): Tergite VII dull due to coarse isodiametric microsculpture, coarsely and densely punctate and setulose, with 1–2 fine punctures between coarse ones; with a row of 12–17 long apical setae curved ventrad in female; tergite VIII very sparsely and finely punctate, shiny in basal half and dull behind due to isodiametric microsculpture either very superficial to obliterate or coarse, respectively. Chetotaxy as for S. montanus .

Legs: as for subgenus. Profemora in dorsal view slightly tumid in male.

Aedeagus ( Figs 55, 59 ): apex of median lobe in lateral view slightly tapered, with apex blunt, in dorsal view subtriangular, with left margin straight and right margin convex; its tip wide, often sidelong (and thence looking somewhat pointed); internal sac with distal basal bulb small, smaller than aedeagus apex in dorsal view; body subcylindric and well separated from proximal basal bulbs in lateral view.

Female gonocoxite IX ensiform, slightly curved laterad, and slightly dilated apically ( Figs 37, 40 ). Receptacle incrassate, slightly to indistinctly Y-shaped, with shorter horn barely separat- ed from or absorbed by a longer horn, respectively ( Figs 50–51 ).

GEOGRAPHICDISTRIBUTION.NorthernLaosandnorthern Vietnam (Phu Tho, Son La, Nghe An, and Ha Tinh provinces); southern China (Sichuan and Yunnan).

HABITATS AND HABITS. Major part of specimens examined have been hand collected or taken using pitfall traps in montane monsoon broad-leaved forests at 400–1340 m altitudes.

COMMENTS. This species was described and then considered as the eastern subspecies (variety) of S. scythropus [ Andrewes, 1923, 1930; Csiki, 1932] until listed as its junior synonym by Lorenz [1998], and authors followed him repeatedly. The original description, however, makes no doubt about not only species status but also rather distant relationship of S. scythropus and S. dissolutus .

My re-examination of S. kalyakini has revealed that its major distinctive feature, i.e., no distal basal bulb in the inverted and inflated internal sac of aedeagus,had come from confusion.Because the dissected male paratype conserved for long in alcohol, this bulb proved to be not everted through preparation and thence invisible. The other differences of S. kalyakini from S. dissolutus are subtle. The elytral ridges are entire (vs. obliterate in eleven or very superficial in three examined specimens of S. dissolutus ); the pronotum barely longer, PW/PL 0.82–0.88 (0.84), and BL 13.6–15.6 mm (mere formality). This, combined with distribution patterns of the two species compared, invites hardly more than subspecies status for S. kalyakini .

Another local population from Sichuan, China, is very similar to the other ones of S. dissolutus in all adult characters, including aedeagal ones ( Figs 56–57, 59–60 ), but dorsal pilosity slightly denser and female gonocoxite IX slightly shorter (compare Fig.34 and Fig. 37 or 40).On the other hand, the locality recorded is much closer to the only known locality of S. yunnanensis (Gongshan, northwestern Yunnan, China) than to any hitherto recorded locality of S. dissolutus . According to the description, S. yunnanensis is only based on the female holotype and has no difference from S. dissolutus other than densely pilose elytral intervals. To clarify interrelations of the three taxa more material is required.

Figures

Figs 1—15. Sternite VIII in female: 1 — Stenaptinus beckeri; 2 — S. tamdaoensis; 3 — S. tripustulatus; 4 — S. dissolutus from China; 5 — S. obliteratus; 6 — S. montanus sp.n.; 7 — S. dissolutus from Vietnam; 8 — S. guanxiensis; 9 — S. bidoupensis; 10 — S. dissolutus kalyakini; 11 — S. glabricollis sp.n.; 12 — S. ngoclinhensis; 13 — S. bipartitus; 14 — Pheropsophus ecuadorensis Hubenthal, 1911; 15 — S. lissoderus from Thailand; ic — internal carina; sa — apical setae. Scale bar: 1 mm. Рис. 1—15. Стернит VIII самки: 1 — Stenaptinus beckeri; 2 — S. tamdaoensis; 3 — S. tripustulatus; 4 — S. dissolutus иЗ КитаЯ; 5 — S. obliteratus; 6 — S. montanus sp.n.; 7 — S. dissolutus иЗ Вьетнама; 8 — S. guanxiensis; 9 — S. bidoupensis; 10 — S. dissolutus kalyakini; 11 — S. glabricollis sp.n.; 12 — S. ngoclinhensis; 13 — S. bipartitus; 14 — Pheropsophus ecuadorensis Hubenthal, 1911; 15 — S. lissoderus иЗ Таиланда; ic — внутренний киль; sa — апикальные Щетинки. МасШтаб: 1 мм.

Figs 16—30. Tergite VIII in female: 16 — Stenaptinus beckeri; 17 — S. tamdaoensis; 18 — S. ngoclinhensis; 19 — S. dissolutus from China; 20 — S. guanxiensis; 21 — S. montanus sp.n.; 22 — S. dissolutus kalyakini; 23 — S. obliteratus; 24 — S. bidoupensis; 25 — S. dissolutus from Vietnam; 26 — S. glabricollis sp.n.; 27 — S. tripustulatus; 28 — Pheropsophus ecuadorensis; 29 — S. bipartitus; 30 — S. lissoderus from Thailand; adr — apical depigmented region; as — anterior sclerotized region; psa — postero-apical sclerotized region; psa — posteromedian sclerotized region. Scale bar: 1 mm. Рис. 16—30. Тергит VIII самки: 16 — Stenaptinus beckeri; 17 — S. tamdaoensis; 18 — S. ngoclinhensis; 19 — S. dissolutus иЗ КитаЯ; 20 — S. guanxiensis; 21 — S. montanus sp.n.; 22 — S. dissolutus kalyakini; 23 — S. obliteratus; 24 — S. bidoupensis; 25 — S. dissolutus иЗ Вьетнама; 26 — S. glabricollis sp.n.; 27 — S. tripustulatus; 28 — Pheropsophus ecuadorensis; 29 — S. bipartitus; 30 — S. lissoderus иЗТаиланда; adr— апикальнаЯ депигментированнаЯобласть; as— переднЯЯ склеротиЗациЯ; psa— постеро-апикальнаЯсклеротиЗациЯ; psm — постеро-медиальнаЯ склеротиЗациЯ. МасШтаб: 1 мм.

Figs 31—45. Urite IX ventrally in female: 31 — Stenaptinus beckeri; 32 — S. lissoderus from Thailand; 33 — S. tripustulatus; 34 — S. dissolutus from China; 35 — S. tamdaoensis; 36 — S. bidoupensis; 37 — S. dissolutus kalyakini; 38 — S. guanxiensis; 39 — S. montanus sp.n.; 40 — S. dissolutus from Vietnam; 41 — S. obliteratus; 42 — S. ngoclinhensis; 43 — S. glabricollis sp.n.; 44 — Pheropsophus ecuadorensis; 45 — S. bipartitus; bc — bursa copulatrix; gcx — gonocoxite; lsc — lateral sclerite. Scale bar: 1 mm. Рис. 31—45. Урит IX самки, вентрально: 31 — Stenaptinus beckeri; 32 — S. lissoderus иЗ Таиланда; 33 — S. tripustulatus; 34 — S. dissolutus иЗ КитаЯ; 35 — S. tamdaoensis; 36 — S. bidoupensis; 37 — S. dissolutus kalyakini; 38 — S. guanxiensis; 39 — S. montanus sp.n.; 40 — S. dissolutus иЗ Вьетнама; 41 — S. obliteratus; 42 — S. ngoclinhensis; 43 — S. glabricollis sp.n.; 44 — Pheropsophus ecuadorensis; 45 — S. bipartitus; bc — копулЯтивнаЯ сумка; gcx — гонококсит; lsc — латеральный склерит. МасШтаб: 1 мм.

Figs 46—53. Apex of abdomen and reproductive tract of female: 46—47 — Stenaptinus montanus sp.n.; 48 — S. glabricollis sp.n.; 49 — S. guanxiensis; 50 — S. dissolutus from Vietnam; 51 — S. dissolutus from China; 52 — S. obliteratus; 53 — S. bipartitus; bc — bursa copulatrix; gcx — gonocoxite IX; rp — receptacle; sa — apical setae; sg — spermathecal gland. Scale bars: 1 mm. Рис. 46—53. ВерШина брюШка и репродуктивный тракт самки: 46—47 — Stenaptinus montanus sp.n.; 48 — S. glabricollis sp.n.; 49 — S. guanxiensis; 50 — S. dissolutus иЗ Вьетнама; 51 — S. dissolutus иЗ КитаЯ; 52 — S. obliteratus; 53 — S. bipartitus; bc — копулЯтивнаЯ сумка; gcx — гонококсит IX; rp — рецептакул; sa — апикальные Щетинки; sg — желеЗа сперматеки. МасШтаб: 1 мм.

Figs 54—69. Median lobe of aedeagus with everted and inflated internal sac: 54, 58 — Stenaptinus obliteratus; 55, 59 — S. dissolutus from Vietnam; 56, 60 — S. dissolutus from China; 57, 61 — S. glabricollis sp.n.; 62, 66 — S. montanus sp.n.; 63, 67 — S. bidoupensis; 64, 68 — S. guanxiensis; 65, 69 — S. tamdaoensis; 54—57, 62—65 — left aspect; 58—61, 66—69 — dorso-apical aspect; b — body of internal sac; bbd — distal basal bulb; bbp — proximal basal bulb. Scale bars: 1 mm. Рис. 51—66. СреднЯЯ долЯ Эдеагуса с вывернутым и надутым внутренним меШком: 54, 58 — Stenaptinus obliteratus; 55, 59 — S. dissolutus иЗ Вьетнама; 56, 60 — S. dissolutus иЗ КитаЯ; 57, 61 — S. glabricollis sp.n.; 62, 66 — S. montanus sp.n.; 63, 67 — S. bidoupensis; 64, 68 — S. guanxiensis; 65, 69 — S. tamdaoensis; 54—57, 62—65 — слева; 58—61, 66—69 — дорЗо-апикально; b — тело внутреннего меШка; bbd — дистальный баЗальный пуЗырь; bbp — проксимальный баЗальный пуЗырь. МасШтаб: 1 mm.

Figs 70—75. Dorsal habitus: 70 — Stenaptinus dissolutus from Vietnam; 71 — S. dissolutus from China; 72 — S. tamdaoensis; 73 — S. guanxiensis; 74 — S. obliteratus; 75 — S. montanus sp.n., male, paratype. Рис. 70—75. Габитус, дорЗально: 70 — Stenaptinus dissolutus иЗ Вьетнама; 71 — S. dissolutus иЗ КитаЯ; 72 — S. tamdaoensis; 73 — S. guanxiensis; 74 — S. obliteratus; 75 — S. montanus sp.n., паратип, самец.