Morphostenophanes vietnamicus ( Kaszab, 1980 )

Zhou, De-Yao, 2020, A revision of the genus Morphostenophanes Pic, 1925 (Coleoptera, Tenebrionidae, Stenochiinae, Cnodalonini), Zootaxa 4769 (1), pp. 1-81 : 50-53

Morphostenophanes vietnamicus ( Kaszab, 1980) ḪṀẎȐAEƤ

( Figs. 30 A–D; 31U–X, Z; 32F, V–X; 33F, L)

Promorphostenophanes atavus vietnamicus Kaszab, 1980: 219 (type locality: Hoang Lien Son: Gebirge bei Sa pa [=Mount Sapa], Vietnam), figs.122–124 (pro- and mesotibia, parameres); synonymized by Masumoto & Bečvář 2008: 210; Gao & Ren 2009: 307 (in introduction).

Pseudomorphostenophanes (sic) atavus vietnamicus: Kaszab 1980: 218 (in figure caption).

Morphostenophanes vietnamicus ( Kaszab, 1980) : Masumoto & Bečvář 2008: 210, fig.5, also misspelled in 207 as ‘ M. vietnamensis ’ in figure caption; Gao & Ren 2009: 308 (in introduction).

Materials examined. (8♂♂, 1♀). VIETNAM: 1♂, 1♀ ( MYNU, a sample of muscle tissue was preserved in 99.7% ethanol at –18 °C in CZDY) , Lào Cai Province, Mount Sapa , 1600 m, native collector ; 2 ♂ ♂ ( CZDY) , Yên Bái Province, Mù Cang Ch ải District , 1700 m, 2016.v–vii, native collector ; 1♂ ( HNHM, identified by Ottó Merkl) , Lào Cai Province, 16 km W of Sa Pa, 1800 m, first Frontier base camp, 1998.iii.18, under bark, L. Peregovits & T. Vásárhelyi ; 4♂♂ ( HNHM, identified by Ottó Merkl) , Yên Bái Province, Mù Cang Ch ải District, Che Tao commune, Mù Cang Ch ải Species and Habitats Conservation Area , around Cong Troi ( Gate to Heaven ) Pass , 21.7686°N, 104.0442°E, 1940 m, upper montane evergreen forest, hand-collected from dead trees at night, 2019.ix.24–29, Ottó Merkl & Phu Pham Van .

Diagnosis. Body large and elongate, aeneous, with metallic luster. Elytra striate, with aspect ratio of 1.8 in male, and of 1.7 in female; protibiae and mesotibiae each bulged in apical 2/5.

Redescription. Male ( Fig. 30A, C ), aeneous, with metallic luster. Body elongate, length 22.3–23.9 mm, width 8.1–8.7 mm, strongly convex dorsad, noticeably constricted between pronotum and elytra.

Head ( Fig. 31U, W ) transversely subquadrate, densely and markedly punctate, with outer margin strongly notched between genae and clypeus; clypeus transversely hexagonal, gently bent downwards in front, convex before middle of the frontoclypeal suture, with anterior margin straight; frontoclypeal suture furrowed, becoming weaker laterad, widely U-shaped; genae strongly raised, depressed before eyes, strongly and roundly produced anterolaterally; frons broad, anterior part gradually sloping forwards; eyes transversely reniform, strongly convex laterally; inner ocular sulci shallowly grooved along inner margins; tempora slightly convex, punctures as those on frons. OI = 48.7. Antennae ( Fig. 32F ) slender, reaching basal 2/7 of elytra, with antennomeres weakly thickened to apices; relative lengths of antennomeres: 0.77: 0.37: 1.28: 1.21: 1.34: 1.38: 1.33: 1.22: 1.21: 1.14: 1.33. Mentum ( Fig. 31W ) rounded, medial surface weakly wrinked, coarsely punctate, with several large pores bearing long setae; gradually rising from base to apex, depressed along each side.

Pronotum ( Fig. 31V ) quadrate, PW/PL = 1.13, widest slightly before anterior third, anterior margin strongly projecting in middle, with marked marginal border; lateral margins nearly straight, roundly projecting laterally in anterior half, lateral marginal borders thin, visible in dorsal view along anterior half; posterior margin nearly straight, posterior marginal border marked, becoming thinner in middle; anterior angles broadly rounded, posterior angles obtuse; disc convex, finely and sparsely punctate. Scutellum widely triangular, glossy, finely punctate.

Elytra fusiform, widest in middle, EL/EW = 1.8; strongly convex, highest before middle; with 9 continuous furrowed striae, 8 th ending at apical sixth of elytra; 1 st and 9 th; 2 th, 3 rd, and 7 th converging at ends, 4 th, 5 th successively joined 6 th at each end; intervals strongly convex, sparsely and finely punctate.

Prosternum ( Fig. 31X ) shagreened, finely and sparsely punctate; prosternal process declivous, truncate at apex; hypomeron weakly rugulose, shagreened. Metasternum glossy, finely wrinkled on metaventral anterior process. Abdomen weakly depressed, surface smooth in middle and weakly wrinkled on sides and anterior margin of each sternite, sparsely and finely punctate, sternites III and IV sulcate on sides.

Legs slender. Protibiae ( Fig. 32V ) thick, curved in apical fourth, apical 2/5 of inner margins concave, bulged in apical 2/5, pubescent; mesotibiae ( Figs. 31Z , 32W ) weakly curved in apical sixth, apical 2/5 of inner margins concave, bulged in apical 2/5, pubescent; metatibiae ( Fig. 32X ) sinuous, apical half of inner margins pubescent, outer margins depressed before apices.

Aedeagus ( Fig. 33F ) elongate, curved in lateral view; parameres slender, 0.21 as long as total length, with ovoid apex. Sternite VIII ( Fig. 33L ) with apical lobes constricted at base, and expanded posteriorly in lateral view, oblong, slightly curved.

Female ( Fig. 30B, D ). Less shiny and wider than male, length 26.5 mm. OI = 48.7, PW/PL = 1.24; elytra more convex, highest near middle, EL/EW = 1.68; abdomen straight in lateral view. Pro- and mesotibiae without bulges, metatibiae without pubescent sinuosity. Ovipositor elongate, gradually narrowing posteriorly, apex of gonocoxite acute.

Comments. This species is originally treated as a subspecies of Promorphostenophanes atavus by Kaszab (1980). Later, it was elevated to species rank by Masumoto & Bečvář (2008). The unique bulges on inner sides of male pro- and mesotibiae clearly separate it from every other congeners and verify its species-level status.

The known localities of M. vietnamicus are extremely close to Jinping County, southeastern Yunnan, where this species may be found in the future, and thus be recorded in China.

Distribution. ( Map 1 ). North VIETNAM.

Figures

Map 1. Distribution of the Morphostenophanes species. A. Enlargement of Central and Western Yunnan Province.

FIGURE 30. Habitus of Morphostenophanes vietnamicus (Kaszab). Male (A, C), and female (B, D); in dorsal (A, B), and lateral view (C, D). Scale bars = 5 mm.

FIGURE 31. External characters and anatomic structure of Morphostenophanes species in the atavus-group: M. atavus (Kaszab) (A, E, K, P), M. bannaensis Zhou new species (B, G, L, Q), M. birmanicus (Kaszab) (C, H, M, R), M. brevigaster Zhou new species (D, I, N, S), M. lincangensis Zhou new species (E, J, O, T, Y), and M. vietnamicus (Kaszab) (U–X, Z). Male heads in dorsal (A–E, U) and ventral view (F–J, W); male prothoraces in dorsal (K–O, V) and ventral view (P–T, X); female reproductive organs (Y); and male mesotibiae in dorsal view (Z). Scale bars of A–X = 1 mm; Y = 2 mm.

FIGURE 32. External characters of Morphostenophanes species in the atavus-group: M. atavus (Kaszab) (A, G–I), M. bannaensis Zhou new species (B, J–L), M. birmanicus (Kaszab) (C, M–O), M. brevigaster Zhou new species (D, P–R), M. lincangensis Zhou new species (E, S–U), and M. vietnamicus (Kaszab) (F, V–X). Male antennae in dorsal view (A–F). Male protibiae in dorsal view (G, J, M, P, S, V), mesotibiae in ventral view (H, K, N, Q, T, W) and metatibiae in dorsal view (I, L, O, R, U, S). Scale bars = 2 mm.

FIGURE 33. Anatomic structures of Morphostenophanes species in the atavus-group: M. atavus (Kaszab) (A, G), M. bannaensis Zhou new species (B, H), M. birmanicus (Kaszab) (C, I), M. brevigaster Zhou new species (D, J), M. lincangensis Zhou new species (E, K), and M. vietnamicus (Kaszab) (F, L). Aedeagi (A–F) and male sternites VIII (G–L); in dorsal view (d), lateral view (l), and enlargements of parameres apices (p). Scale bars = 1 mm; all parameres apices not to scale.