Stenaptinus Maindron, 1906

Fedorenko, D. N., 2020, Stenaptinus (Coleoptera: Carabidae: Brachininae) of Vietnam. Note 1, Russian Entomological Journal 29 (4), pp. 361-376 : 362-363

Stenaptinus Maindron, 1906

Maindron, 1906: 15; Erwin, 1970: 34; 1971: 281. — Pheropsophus (part.): Solier, 1833: 461; 1834: 655–658, pl.16, fig.4; Chaudoir, 1876: 16; Arrow, 1901: 193; Hubenthal, 1911: 547; 1914: 437; Andrewes, 1930: 270; Csiki, 1932 –1933: 1595–1604; Jeannel, 1949: 1084; Lorenz, 1998: 14; 2005: 14; Hrdlička, 2003: 217; 2017b: 479.

— subg. Parapheropsophus Hubenthal,1914 (type species: Brachinus verticalis Dejean, 1825 ); Jeannel, 1949: 1084; Erwin, 1970: 34; 1971: 281.

— subg. Aptinomorphus Jeannel,1949:1084 (type species: Pheropsophus acutecostatus Fairmaire, 1892 ); Erwin, 1970: 36; 1971: 281.

Type species: Pheropsophus krichna Maindron, 1906 , designated by Jeannel, 1949.

REDESCRIPTION. Unnecessary here, except for notes on comparative morphology of terminal abdominal urites and reproductive tract in female.

Sternite VIII ( Figs 1–13, 15 ): divided into two hemisternites by fairly narrow membranous area and more or less (the tripustulatus -group) widely membranous mediobasally and medioapically, with a subquadrate basolateral apophysis and 1–2 internal (dorsal) carinae on each side, inner carina being oblique and outer carina longitudinal. The species of the javanus -group have either both carinae subequally developed or one of them much reduced, and the only carina traceable is a supposedly derived condition characteristic of the other groups. The inner carina has been retained in the dissolutus -group and outer carina in Aptinomorphus , the tripustulatus -group and the bidoupensisgroup. The inner carina (or the only carina traceable) runs either near (the dissolutus -group, the javanus -group) or at a considerable distance from the corner ( Aptinomorphus , the tripustulatus - group, the bidoupensis -group), ranging between middle and outer margin of the basolateral apophysis.

Pilosity dense except in the bidoupensis -group. Apical setae, especially median ones, very slightly differentiated from ventral pilosity in Aptinomorphus only,otherwise strong, straight or curved inward (dorsad); arranged in row of about five (the tripustulatus -group), or 6–8 ( Aptinomorphus , the bidoupensisgroup), or multiple (the dissolutus -group, the javanus -group) setae. The tripustulatus -group is also very distinctive in having medio-apical sclerite projecting apicad.

Tergite VIII ( Figs 16–27, 29–30 ) with three sclerotized (pigmented) regions on each side, termed anterior sclerotization (as), posterior sclerotization (ps), and smaller lateral sclerotization (ls), with ps being either median (psm) or apical (psa) in position.These regions are more or less separated by depigment- ed, transparent, zones and followed by apical depigmented region (adr). All the taxa have as similar in shape, except that the tripustulatus -group is very distinctive in having as very large, strongly sclerotized, not or barely separated from vague psa, combined with ls indistinct and adr very short, with dense spiniform setae. The latter three characters (psa, ls, adr) drive this group closer to the bidoupensis -group, of which members well-defined triangular psa and sparsely setulose adr are characteristic. Aptinomorphus is similar to either and shares large as with species of the tripustulatus -group. The dissolutus -group and the javanus -group are much more similar to each other than to the remaining groups in all integral parts, primarily adr long, a third as long as the tergite, tuberculate and setulose, and also by as triangular and psm subrectangular, narrow and transverse. Interspecific differences within the bidoupensis -group and the dissolutus -group are slight and more material is required to clarify significance of these differences and geographical variability of the integral parts.

Urite IX ( Figs 31–43, 45 ): similar in the taxa examined, except that gonocoxites are very short in Aptinomorphus or very long and sparsely setulose along dorsal edges in the tripustulatus -group; this latter pattern, combined with ventral membrane grooved to receive gonocoxites and a slender longitudinal sclerotization between these grooves, makes the tripustulatus -group very peculiar within the genus.

Reproductive tract ( Figs 47–48, 50–53 ): bursa copulatrix either membranous or with two lateral sclerites ( Fig. 45 ), its narrow proximal portion telescoped into large distal portion. Spermathecal receptacle short Y-shaped, more or less asymmetric owing to one horn somewhat shortened or absorbed by the incrassate body (secondarily bulbous in some species), about as long as seminal canal, which enters bursa copulatrix ventro-apically.

GEOGRAPHIC DISTRIBUTION. Throughout Paleotropical realm north to the southernmost Palearctic and east to Australia.

COMMENTS. From the above comparison one could conclude or suggest that (1) the tripustulatus -group is peculiar and may be close to the bidoupensis -group; (2) the dissolutus -group and the javanus -group are close to each other than to any other group; (3) Aptinomorphus seems to be more primitive than the other taxa compared, being supposedly closer to the first couple.

The javanus -group and the dissolutus -group with certainty, and the bidoupensis -group probably, belong to the nominotypical subgenus, whereas the tripustulatus -group is most likely to be conformable to the subgenus Parapheropsophus . However, we do not use this latter name here because the type species of the subgenus has not been dissected.

While Pheropsophus krichna Maindron, 1906 is the type species of the genus, in describing Stenaptinus Maindron [1906] mentioned that Ph. melancholicus ( Schmidt-Göbel, 1846) can be considered as type of this section of aptiniform Pheropsophus , which phrase meant predication rather than surmise. The combination ‘ Pheropsophus melancholicus ’ was first introduced by Chaudoir [1876] for a species of Pheropsophus he misidentified, therefore S. melancholicus : ( Maindron, 1906) = S. melancholicus : ( Chaudoir, 1876) = S. scythropus ( Andrewes, 1923) , non Brachinus melancholicus ( Schmidt-Göbel, 1846) .

According to the description, the subgenus Aptinomorphus includes two aptiniform Madagascan species defined by the elytra having no apical setulose fringe, nor humeri following apterous condition of the adult, and also by a longer pronotum and the body dorsum without variegated pattern. Erwin [1970] used also sharply carinate elytral ridges (vs. wide and costate) to differentiate Aptinomorphus from Stenaptinus sensu Erwin, 1970 (= Stenaptinus sensu Maindron, 1906 ). All these differences, however, do not serve their purpose because two examined females S. bipartitus (Fairmaire, 1868) have been found to have while all examined species of Stenaptinus sensu Erwin, 1970 have no apical elytral fringe, and the elytral ridges are very narrow in most species of the latter taxon. Rather distinctive female genitalia of Aptinomorphus may be used at the moment for the purpose instead: very short and broad gonocoxite IX [ Erwin, 1970], bursa copulatrix with lateral sclerites in its distal part (vs. membranous), tergite VIII sclerotized in a different manner, and sternite VIII with apical setae only slightly differentiated from the pilosity around ( Fig. 13 ).

The species reviewed below are arranged into two separate species groups, the bidoupensis -group and the dissolutus -group, which include more than a dozen Oriental species combined. These are confined to northern Indochina west to northeastern India and Bhutan, while reaching southern China. The eastern species are very similar in appearance, and some of them are sympatric and often live syntopically. At the moment, I consider two western species, S. aptinoides ( Chaudoir, 1876) and S. prophylax ( Heller, 1903) as incertae sedis. These, as well as the species from the Sunda Islands are beyond the scope of this paper and thence not included in the key below. This is true also of two little-known species from Myanmar, S. cardoni ( Maindron, 1898) and S. heathi ( Arrow, 1901) .

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.