Morphostenophanes aenescens Pic, 1925

Zhou, De-Yao, 2020, A revision of the genus Morphostenophanes Pic, 1925 (Coleoptera, Tenebrionidae, Stenochiinae, Cnodalonini), Zootaxa 4769 (1), pp. 1-81 : 10-13

Morphostenophanes aenescens Pic, 1925 ṚẘẎȐAEƤ

( Figs. 3 A–K; 4A–D; 16A, F; 17O, T; 18A, L–N; 19P; 20A, L)

Morphostenophanes aenescens Pic, 1925: 7 (type locality: Yunnan), Kaszab 1941: 10, fig. 3; Ando & Ren 2006: 90; Masumoto & Bečvář 2008: 206, fig. 1 [misidentification]; Löbl et al. 2008: 344; Gao & Ren 2009: 310 , figs. 1–7, 41 [misidentification].

Morphostenophanes aenescens var. diversus Pic, 1925: 7 , synonymized by Kaszab 1941: 10, Löbl et al. 2008: 344 (in synonymy); Gao & Ren 2009: 310 (in synonymy).

Morphostenophanes aenescens var. subparallelus Pic, 1925: 7 , synonymized by Kaszab 1941: 10, Löbl et al. 2008: 344 (in synonymy); Gao & Ren 2009: 310 (in synonymy).

Type material examined. Lectotype designated here: Yunnan [handwriting on pale label] // V. subparallelus Pic [handwriting on pale yellow label] // coll Pic [handwriting on pale yellow label] // Morphostenophanes aenescens Pic det. dr. Kaszab [handwriting of the first two lines on pale label] // MUSÉUM PARIS 1958 coll. M. PIC // SYN- TYPE [red label] // SYNTYPE Morphostenophanes aenescens var. subparallelus Pic, 1925 // MNHN EC9694 // LECTOTYPE, Morphostenophanes aenescens Pic, 1925 , ♂, des. De-Yao Zhou 2019 [printed on white label] (male, MNHN, Fig. 3 A–C) . Paralectotype labelled: Yunnan [handwriting on pale label] // Morphostenophanes aenescens Pic [handwriting on pale label] // MUSÉUM PARIS 1958 coll. M. PIC // SYNTYPE [red label] // SYNTYPE Morphostenophanes aenescens Pic, 1925 // MNHN EC9693 // PARALECTOTYPE, Morphostenophanes aenescens Pic, 1925 , ♂, des. De-Yao Zhou 2019 [printed on white label] (1 female, MNHN, Fig. 3G, H ). Both types examined through ten photographs taken by Antoine Mantilleri .

Comments on type material. This species was originally described from an unspecified number of specimens of Pic’s collection, which is now deposited in MNHN. However, characteristic descriptions of both sexes and two varieties, i.e. Morphostenophanes aenescens var. diversus , and M. aenescens var. subparallelus , were presented in the original description ( Pic, 1925); therefore at least four specimens including both sexes were examined by Pic. It is difficult to determine the exact number of the specimens in the type series because of the mess of Pic’s collection. Kaszab (1941) placed both varieties as junior synonyms of Morphostenophanes aenescens .

Here the author examined one female syntype of M. aenescens , and one male syntype of M. aenescens var. subparallelus with a handwritten identification label of Kaszab.

Additional material examined (5♂♂, 2♀♀). CHINA: Yunnan : 1♂ ( CZDY, a sample of muscle tissue was preserved in 99.7% ethanol at –18 °C), Qujin City, Xishan District, Mount Cui , 25°32’57.96’’N, 103°42’04.92’’E, ca. 2000 m, 2015.ix.20, Ye-Hui Fang ; 1♂ ( CZDY, a sample of muscle tissue was preserved in 99.7% ethanol at –18 °C), Qujin City, Zhanyi District, Zhujiangyuan , ca. 2100 m, 2018.viii, Zheng Zhou ; 1♀ ( CJQY), Qujin City, Zhanyi District, Longxijian , 25°54’18’’N, 103°55’52.18’’E, 2222 m, 2019.vii.30, Jia-Mian Liang ; 1♂ ( CZRZ, a sample of muscle tissue was preserved in 99.7% ethanol at –18 °C in CZDY), Qujin City, Fuyuan County, Fa’ao Village , Hejiafangzi, 2018.xii, native collector ; 2♂♂ ( ERPC) , 1♀ ( CZDY), Mianmianshan , 20 km W Lugu Lake, 20°42’N, 100°34’E, 2005.viii, V. Siniaev .

Diagnosis. Medium-sized, moderately elongate and convex, color dark grayish blue, somewhat purplish. Elytra with densely and irregularly scattered round or oval segments of encircled striae, each encircled area moderately convex, areas around them with pinkish luster ( Fig. 3E, J ). Head and pronotum densely scattered large and deep punctures, some connected with each other. Elytra widest in apical 2/5. Protibiae nearly straight.

Redescription. Male ( Fig. 4A, C ). Dark greyish blue, antennae, mouthparts, and claws dark brown, areas around encircled segments of elytral striae pinkish, all legs and abdomen purplish, shagreened. Body moderately elongate, length 18.6–20.4 mm, width 6.7–7.4 mm, strongly convex, noticeably constricted between pronotum and elytra.

Head ( Fig. 16A, F ) quadrate, finely microsculptured, with densely scattered large and deep punctures, some connected with each other; genal areas before eyes impunctate; with outer margin distinctly notched between genae and clypeus; clypeus transversely hexagonal, gently bent downwards in front, anterior margin weakly emarginate, frontoclypeal suture deeply grooved, widely U-shaped; genae strongly raised, depressed before eyes, strongly and roundly produced anterolaterally; frons broad, anterior part gradually sloping forwards, vertexal lateral impressions and vertexal median impression vaguely presented; eyes transversely reniform, strongly convex laterally; inner ocular sulci shallowly grooved along inner margins, becoming broader posteriorly; tempora moderately convex, coarsely punctate. OI = 58.5–60.9. Antennae ( Fig. 18A ) slender, reaching basal fifth of elytra, with antennomeres weakly thickened to apices; relative lengths of antennomeres: 0.60: 0.26: 0.90: 0.82: 0.87: 0.85: 0.83: 0.82: 0.80: 0.73: 0.87. Mentum ( Fig. 16F ) transversely quadrate, lateral margins nearly straight; medial surface coarsely punctate, with several large pores with long setae, gradually rising anteriorly, depressed along both sides.

Pronotum ( Fig. 17O ) barrel-shaped, PW/PL = 1.14–1.17, widest slightly anterior to midpoint, anterior margin bisinuate, anterior marginal border marked; lateral margins weakly rounded, more or less constricted in posterior sixth, lateral marginal borders thin, visible in dorsal view slightly exceeding anterior half, or between anterior fourth and the half, somewhat sinuate; posterior margin nearly straight, more or less emarginate, posterior marginal border marked; anterior angles rounded, more or less bent ventrally; posterior angles obtuse; disc strongly convex, shagreened, with densely scattered large and deep punctures, some connected with each other, presenting a longitude impression along midline, with a pair of vague impressions on both sides. Scutellum triangular, coarsely punctate.

Elytra elongate oval, widest in apical 2/5, EL/EW = 1.80–1.90; strongly convex, highest near middle; with densely and irregularly scattered round or oval segments of striae, each encircled area moderately convex; intervals slightly wrinkled, finely punctate.

Prosternum ( Fig. 17T ) shagreened, finely and sparsely punctate; prosternal process declivous, truncate at apex; hypomeron strongly rugulose, shagreened. Metasternum weakly wrinkled. Abdomen ( Fig. 19P ) depressed, surface somewhat rough and weakly wrinkled, densely and markedly punctate; sternites III and IV each depressed in posterior middle, with central portion of each impressions weakly convex.

Legs slender. Protibiae ( Fig. 18L ) nearly straight, slightly recurved behind apical half, apical 3/5 of inner margins emarginated and pubescent; mesotibiae ( Fig. 18M ) nearly straight, weakly curved in apical seventh, apical half of inner margins weakly pubescent; metatibiae ( Fig. 18N ) nearly straight, apical 3/5 of inner margins weakly pubescent, outer margins depressed before apices.

Aedeagus ( Fig. 20A ) elongate, curved in lateral view; parameres slender, 0.23 as long as total length, recurved in middle in lateral view, with ovoid apex, slightly bent ventrally in lateral view. Sternite VIII ( Fig. 20P ) with apical lobes broadly hooked in lateral view.

Female ( Fig. 4B, D ). Stouter than male, length 21.5 mm. IE/TD = 58.6, PW/PL = 1.21; elytra more convex, highest behind middle, EL/EW = 1.74; abdomen straight in lateral view; without impressions on sternites. Ovipositor shortened, abruptly narrowing terminally from apical third.

Variability. Only one male from Xishan District, Qujin city has the pronotum distinctly constricted before the base (as shown in Fig. 17 O-XsD), as shown in the lectotype. Species from Fuyuan County, Qujin City have pronotal anterior angles distinctely bent ventrally, lateral margin markedly projecting laterally at widest point, lateral marginal borders slightly sinuate (as shown in Fig. 17 O-FyC).

Comparative notes. Morphostenophanes aenescens most resembles M. yunnanus . It can be readily distinguished from M. yunnanus by its greyish blue body color (grey-black in the latter), head and pronotum with large and deep punctures (those in the latter are much smaller and shallower), stouter elytra than the latter, and nearly straight male protibiae (curved at apical third in the latter).

Comments. Morphostenophanes aenescens is the type species of Morphostenophanes . Pic (1925) gave a very brief description of this species, with an imprecise locality information of ‘Yunnan’. According to the original description, M. aenescens is shining and glossy, black or pitch-black, dorsum bronze (‘Nitidus, glaber, nigro aut piceo metallicus, supra aeneus’). Within the description, Pic described two varieties, i.e. M. aenescens var. diversus , and M. aenescens var. subparallelus . The former is somewhat greenish (‘aliquot viridescens’), and the latter has the habitus more parallel, impressions on elytra more coarsely punctate (‘presente une forme plus étroite, presque parallele et les elytres ont quelques gros points nets dans leurs impressions’). Later, Kaszab (1941) synonymized these two variants. In his key, Kaszab described this species as black, with very weak metallic luster (‘Schwarz, mit sehr schwachem Metallschimmer’). The identification label hand-written by Kaszab (shown in Fig. 3F ) also attests that he did examine the type series. In Kaszab’s work (1941), only one indistinct photo of M. aenescens was displayed. Subsequent works ( Masumoto & Bečvář 2008; Gao & Ren 2009) also presented photos of male M. aenescens , but they are different from each other.

Though the newly designated lectotype and paralectotype were seriously damaged, some important features were visible. Their heads and pronota are covered with large deep punctures, some connected with each other; prothorax of male constricted before base; and elytra possess rows of small encircled segments of striae, each with pinkish luster. The author found three males and two female specimens possessing these characteristics, thus allowing for a better characterization and more accurate location of this species. The author also found many similar specimens from Dali Prefecture and neighboring areas, distinguished from M. aenescens by darker body color, more glossy head and pronotum, strongly curved protibiae and sinuous metatibiae (nearly straight in M. aenescens ), elytral impressions without pinkish luster. Thus these specimens are identified as new and name as M. yunnanus . Based on the revised diagnostic characters and known locality of M. aenescens , specimens examined by Masumoto & Bečvář (2008) and the record reported by Gao & Ren (2009) from Hetaoping, Binchuan County are considered as misidentifications of M. yunnanus ; another pair of specimens cited by Gao & Ren (2009) from Longxin, Longling County may belongs to M. gaoligongensis , which belongs to the elegantulus -group.

Pinkish luster on elytral impressions is a common character in M. cuproviridis , sometimes observed in M. aenescens yelang , and vaguely shown in M. papillatus , and on some individuals of M. iridescens . These species together with M. aenescens are successively distributed from east Yunnan to east Guizhou ( Map 1 ). This character is also faintly present on the smallest individuals of M. yunnanus , which occurrs in midwestern Yunnan. Therefore, such character may reveals closer relations of these species within aenescens -group, and shows a gradual spreading and speciation scene from west to east.

Distribution. ( Map 1 ) CHINA: Yunnan.

Figures

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

FIGURE 3. Type specimens and labels of Morphostenophanes aenescens Pic. Male syntype of M. aenescens var. subparallelus Pic in dorsal (A), ventral (B), and lateral (C) view, with enlargements of pronotum (D) and elytra (E). Female syntype of M. aenescens Pic in in dorsal (G) and lateral (H) view, with enlargements of pronotum (I) and elytra (J). Scale bars of A–C, G, H = 5 mm; E, F, I–K not to scale.

FIGURE 4. Habitus of Morphostenophanes aenescens Pic. Male from Xishan District, Qujin City (A, C) and female from Mianmian Mountain (B, D); in dorsal (A, B) and lateral view (C, D). Scale bars = 5 mm.

FIGURE 16. External characters of Morphostenophanes species in the aenescens- and chongli-group: M. aenescens Pic (A, F), M. cuproviridis Gao & Ren (B, G), M. curvitibialis Zhou new species (C, H, V), M. iridescens Zhou new species (D, I), M. luoxiaoshanus Zhou new species (E, J, U), M. papillatus Kaszab (K, O), M. purpurascens Zhou new species (L, P), M. aenescens yelang Zhou new subspecies (M, Q), M. chongli Zhou new species (N, R), and M. yunnanus Zhou new species (S, T). Male heads in dorsal view (A–E, K–N, S), and in ventral view (F–J, Q–R, T). Flanks of mesosterna (U, V). Scale bars of A–R = 1 mm, S–V not to scale. Abbreviations: ptp, posterior tentorial pits. Full meaning of all abbreviations of M. yunnanus habitats expounded as in Map 2.

FIGURE 17. Male prothoraces of Morphostenophanes species in the aenescens- and chongli-group: M. cuproviridis Gao & Ren (A, F), M. curvitibialis Zhou new species (B, G), M. iridescens Zhou new species (C, H), M. luoxiaoshanus Zhou new species (D, I), M. papillatus Kaszab (E, J), M. purpurascens Zhou new species (K, P), M. aenescens yelang Zhou new subspecies (L, Q), M. chongli Zhou new species (M, R), M. chongli glaber Zhou new subspecies (N, S), M. aenescens Pic (O, T) and M. yunnanus Zhou new species (S, T); in dorsal view (A–N, K–O, U, d), and in ventral view (F–J, P–T, v). Scale bars of A–N, P–S = 1 mm; O, T, U not to scale. Abbreviations of M. aenescens: XsD, Xishan District; FyC, Fuyuan County. Abbreviations of M. yunnanus habitats expounded as in Map 2, except CDll, Central Dali population; CDls, small individual of Central Dali population.

FIGURE 18. External characters of Morphostenophanes species in the aenescens- and chongli-group: M. aenescens Pic (A, L–N), M. cuproviridis Gao & Ren (B, O–Q), M. curvitibialis Zhou new species (C, R–T), M. iridescens Zhou new species (D, U–W), M. luoxiaoshanus Zhou new species (E, X–Z), M. papillatus Kaszab (F), M. purpurascens Zhou new species (G, Gv), M. aenescens yelang Zhou new subspecies (H), M. chongli Zhou new species (I), and M. yunnanus Zhou new species (J), and M. chongli glaber Zhou new subspecies (K). Male antennae in dorsal view (A–K), a variation of antennomere XI (Gv). Male protibiae, in dorsal view (L, O, R, U, X); mesotibiae, in ventral view (M, P, S, V, Y); and metatibiae, in dorsal view (N, Q, T, W, Z). Scale bars of A–K = 2 mm; L–Z = 1 mm. Full meaning of all abbreviations standing for M. yunnanus habitats expounded as in Map 2.

FIGURE 19. External characters of Morphostenophanes species in the aenescens- and chongli-group: M. aenescens Pic (P), M. cuproviridis Gao & Ren (Q), M. curvitibialis Zhou new species (R), M. iridescens Zhou new species (S), M. luoxiaoshanus Zhou new species (T), M. papillatus Kaszab (A–C, U), M. purpurascens Zhou new species (D–F, V), M. aenescens yelang Zhou new subspecies (G–I, W), M. yunnanus Zhou new species from the type locality (J–L, X), and M. chongli Zhou new species (M–O, Y). Male protibiae, in dorsal view (A, D, G, J, M); mesotibiae, in ventral view (B, E, H, K, N); and metatibiae, in dorsal view (C, F, I, L, O). Male abdomens (P–Y). Scale bars of A–O = 1 mm; P–Y = 2 mm.

FIGURE 20. Anatomic structures of Morphostenophanes species in the aenescens- and chongli-group: M. aenescens Pic (A, L), M. cuproviridis Gao & Ren (B, M), M. curvitibialis Zhou new species (C, N), M. iridescens Zhou new species (D, O), M. luoxiaoshanus Zhou new species (E, P), M. papillatus Kaszab (F, Q), M. purpurascens Zhou new species (G, R, V), M. aenescens yelang Zhou new subspecies (H, S), M. yunnanus Zhou new species from the type locality (I, T, W), M. chongli Zhou new species (J, U) and M. chongli glaber Zhou new subspecies (K). Aedeagi (A–K), male sternites VIII (L–U), and female reproductive organs (V, W); in dorsal view (d), lateral view (l), and enlargements of parameres apices (p). Scale bars of A–U= 1 mm; V–W = 2 mm; all parameres apices not to scale. Abbreviations: al, apical lobes of parameres.