Morphostenophanes yunnanus Zhou

Zhou, De-Yao, 2020, A revision of the genus Morphostenophanes Pic, 1925 (Coleoptera, Tenebrionidae, Stenochiinae, Cnodalonini), Zootaxa 4769 (1), pp. 1-81 : 25-29

Morphostenophanes yunnanus Zhou , new species Ä¢ẎȐAEƤ

( Figs. 12 A–D; 13; 16S, T; 17U; 18J; 19J–L, X; 20I, T, W)

Type materials. CHINA: Yunnan: ♂ (Holotype, SNUC) , Dali Prefecture, Weishan County, Mount Weibao , 2450– 2580 m, 2017.vii.7, Wen-Xuan Bi. Paratypes (65♂♂, 46♀♀) : CHINA: Yunnan: 1♀ ( SNUC) , 1♂, 1♀ ( MHBU) , 10♂♂, 6♀♀ ( CBWX, three samples each including eggs and muscle tissue were preserved in 99.7% ethanol at –18 °C in CZDY) , Dali Prefecture, Weishan County, Mount Weibao , 2450–2580 m, 2017.vii.7, Wen-Xuan Bi; 1♂, 1♀ ( CZDY) , 6♂♂, 4♀♀ ( CBWX) , Dali Prefecture, Weishan County, Mount Weibao , 2400–2500 m, 2015. viii.16–18, Wen-Xuan Bi; 2 ♂♂, 2♀♀ ( CZDY, a sample of muscle tissue was preserved in 99.7% ethanol at –18 °C) , 1 ♂♂, 2♀♀ ( CDZW) , 2♂♂, 2♀♀ ( KIZ) Dali Prefecture, Weishan County, Ma’anshan Country , 25°19’59.67”N, 100°3’13.91”E, 2019.I, Zhi-Wei Dong; 1 ♂ ( CZDY, a sample of muscle tissue was preserved in 99.7% ethanol at –18 °C) , 1♀ ( CZJZ) , Dali Prefecture, Mount Cang , ca. 2100 m, 2018.vii.20, Jia-Zhi Zhang; 13 ♂♂, 6♀♀ ( MYNU) , Dali Prefecture, Mount Cang, Jiangjundong , 2015.vii.27, Xin-Ran Li & Zhi-Wei Qiu; 2 ♂♂, 2♀♀ ( MYNU) , Dali Prefecture, Mount Cang, Malong Peak , 2500 m, 2011.ii.17, Yun-Chun Li & Yong-Sheng Pan; 1 ♂, 1♀ ( CZDY) , Dali Prefecture, Binchuan County, Jizushan Nature Reserve , 25°57’37.75’’N, 100°23’13.38’’E, 2297 m, 2010.vii.12, Xiao-Bin Song; 1 ♂, 1♀ ( MHBU) , 5 ♂♂, 4♀♀ ( CZDY, a sample of eggs tissue was preserved in 99.7% ethanol at –18 °C) Dali Prefecture, Binchuan County, Jizushan Nature Reserve , 2.5 km WS. Jizushan Town , 2400–2600 m, 2019.vi.7, native collector; 4 ♂♂, 2♀♀ ( MYNU) , Dali Prefecture, Binchuan County, Jizushan Nature Reserve , 2350 m, 2016.ii.20, Hao Xu & Jian-Yue Qiu; 1 ♂ ( CZDY, a sample of muscle tissue was preserved in 99.7% ethanol at –18 °C) , Dali City, Binchuan County, nr. Shifenshuiliangzi , 2018.iv.16, native collector. 1♀ ( CZDY) , Dali City , Binchuan County, 2 km N Muzhulong, 2019.iii, native collector. 2♂♂, 2♀♀ ( CBWX, a sample of eggs was preserved in 99.7% ethanol at –18 °C in CZDY) , Mount Wuliang, near De’an Village, Sheyaoqing , 2300–2450 m, 2017.vii.10–11, Wen-Xuan Bi; 2 ♂♂ ( CZDY, a sample of muscle tissue was preserved in 99.7% ethanol at –18 °C) , Lincang City, Yun County, Manwan Town , Shuibatou Village , 24°41’43’’N, 100°21’10’’E, 1942 m, 2016.ii.10, Zi-Chun Xiong; 1♂ ( CZDY) , Lincang City, Yun County, Manwan Town , Shuibatou Village , 2200 m, 2017.viii, Zi- Chun Xiong; 1 ♂, 1♀ ( CZDY) , Lincang City, Manwan Town, Shuibatou Village , 2200 m, 2018.x, Zi-Chun Xiong; 2 ♂♂, 2♀♀ ( MYNU) , Lincang City, Manwan Town , 2016.iii.8, Zi-Chun Xiong; 1 ♂, 1♀ ( CYM) , Lijiang City, Qina Town, Dongfeng Country , 2017.viii.9, Zhen-Lian Ya; 1 ♂ ( CZDY) , Lijiang City, Yongsheng County, Ludila Town , nr. Zhiduping Village , 2018.viii, native collector; 1♂, 1♀ ( MYNU) , 1 ♂ ( CZDY) , 1 ♂, 2♀♀ ( CQL) , Xinping County, Mount Ailao, Laoniuchang , 23°58’27”N, 101°33’18”E, 1987m, in pine forest, 2018.v.24, Lu Qiu & Zhi-Wei Dong; 1 ♂ ( CQL) , Xinping County, Mount Ailao, Gasa Town , Yaonan Village , 2016.v.13, Lu Qiu .

Diagnosis. Medium sized, elongate, moderately convex, uniformly grey-black, elytral encircled segments of striae usually without pinkish luster, in very few individuals with extremely indistinct pinkish luster. Elytra widest at apical 2/ 5 in male, with densely and irregularly scattered round or oval segments of striae, each encircled area moderately convex. Male protibiae curved in apical third, each with dorsal side of inner margin more concave than ventral one.

Description. Male ( Figs. 12A, B, D ; 13 ). Grey-black, shagreened, mouth parts, and tarsi dark brown. Body elongate, length 17.8–22.3 mm, width 6.0– 7.2 mm, moderately convex dorsad, noticeably constricted between pronotum and elytra.

Head ( Fig. 16S, T ) transversely quadrate, finely microsculptured, with densely scattered marked punctures; with outer margin moderately notched between genae and clypeus; clypeus transversely hexagonal, gently bent downwards in front, anterior margin nearly straight, emarginate, clypeal transverse impression marked to absent, frontoclypeal suture deeply grooved, widely U-shaped; genae strongly raised, depressed before eyes, roundly produced anterolaterally; frons broad, anterior part gradually sloping forwards, frontal impressions and vertexal lateral impressions vague to marked, frontal impressions sometimes connected in middle, vertexal median impression shallow, vaguely presented; eyes transversely reniform, strongly convex laterally; inner ocular sulci sharply grooved along inner margins; tempora weakly convex, coarsely punctate. Distance between eyes about 2–2.5 times as transverse diameter of an eye. Antennae ( Fig. 18J ) slender, reaching basal 2/9 to 2/7 of elytra, with antennomeres weakly thickened to each apices. Mentum ( Fig. 16T ) quadrate, lateral margins nearly straight; medial surface sparsely and coarsely punctate, with several large pores with long setae, gradually rising anteriorly, depressed along both sides.

Pronotum ( Fig. 17U ) barrel-shaped, slightly wider than long, widest at or anterior to the midpoint, anterior margin nearly straight, more or less projecting in middle, anterior marginal border marked; lateral margins rounded, more or less widened at widest point, lateral marginal borders thin, visible in dorsal view slightly behind anterior half; posterior margin nearly rounded, emarginate, posterior marginal border; anterior angles rounded or obtuse; posterior angles obtuse or nearly vertical; disc moderately convex, a pair of impressions vague to absent in middle, a stria connecting small strial punctures presented before the posterior marginal border, shagreened, sparsely and finely to coarsely punctate. Scutellum triangular, glossy.

Elytra oblong, widest near apical 2/5, the length about two times the width; moderately convex, with densely and irregularly scattered round or oval segments of striae, each encircled area moderately convex; intervals more or less wrinkled, densely and finely punctate.

Prosternum ( Fig. 17 U-CDls-v) shagreened, finely and sparsely punctate; prosternal process declivous, pointed at apex; hypomeron strongly rugulose, shagreened. Metasternum transversely wrinkled. Abdomen ( Fig. 19X ) depressed, surface somewhat rough and wrinkled, densely and finely punctate; sternites III and IV each shallowly depressed in posterior middle, with central portion of each impressions weakly convex.

Legs slender. Protibiae ( Fig. 19J ) curved in apical third, apical 3/5 of inner margins concave, each with dorsal side of inner margin more concave than ventral one, pubescent; mesotibiae ( Fig. 19H ) curved in apical third, apical half of inner margins pubescent; metatibiae ( Fig. 19L ) more or less sinuous, apical 3/5 of inner margins weakly pubescent, outer margins depressed before apices.

Aedeagus ( Fig. 20I ) elongate, curved in lateral view; parameres slender, about 0.21 as long as total length, with flabellate apex. Sternite VIII ( Fig. 20T ) with apical lobes nearly rounded, each inferior margin projecting, forming a hook.

Female. Wider than male, length 17.9–22.2 mm. OI = 55.6–59.2. Elytra more convex, elytra much wider, widest in middle; abdomen straight in lateral view; without impressions on sternites. Ovipositor ( Fig. 20W ) shortened, abruptly narrowing terminally from apical third.

Variability. This species is widely distributed from central to eastern Yunnan with distinct geographical variation, which can be divided into seven populations. All comparisons are based on the general properties of specimens from the locality of the holotype, i.e., Weibao Mountain. Ranges of all seven populations are shown in Map 2.

The populations from Weibao Mountain, Cang Mountain, and Ma’an Mountain are extremely similar, and are defined here as a Central Dali population (CDl in Figs. 13 , 16 , 17 , 18 ). They are characterized by having clypeus weakly protruding anteriorly, with anterior margin gently rounded and weakly emarginate in middle; antennae reaching basal fourth of elytra; relative lengths of antennomeres: 0.73: 0.34: 1.24: 1.12: 1.16: 1.19: 1.12: 1.02: 1.00: 0.95: 1.12; male OI = 49.4; pronotum barrel-shaped in most individuals, sometimes variable in shape, with anterior angles more strongly projecting anteriorly with lateral margins buckled in middle, PW/PL = 1.03–1.12, disc with densely scattered shallow but conspicuously marked punctures, punctures more or less connected with each other on middle of disc, pronotal anterior angles only weakly protruded, feebly rounded, but in few small individuals more strongly protruding anteriorly, obtusely angled. Female OI = 55.5. Pronotum moderately convex, PW/PL = 1.12–1.21. Elytra wider, EL/EW = 1.74–1.79, dorsum nearly straight, gradually risen posteriorly, highest slightly behind basal half.

The population from Jizu Mountain (JzM in Figs. 13 , 16 , 17 , 18 ) has darker pitch-black body color, head and pronotum more coarsely punctate, punctures on all legs also larger and deeper; head notably narrower, with eyes narrower and less protruding laterally; antennae slightly shorter, with antennomeres III, IV, X and XI notably shorter; head notably narrower; elytral intervals more strongly wrinkled.

The population from Shifenshuiliangzi and adjacent mountains on the east side of Binchuan County is defined here as Eastern Binchuan population (EBc in Figs. 13 , 16 , 17 , 18 ), which resembles the type population, but with widier head, narrower eyes less protruding laterally, distance between eyes extremely longer than transverse diameter of an eye, OI = 55.3 in male, and 2.43 in female. Antennae distinctly shorter, with antennomeres III and IV notably shortened, relative lengths of antennomeres: 0.65: 0.27: 1.05: 0.95: 0.97: 0.99: 0.97: 0.95: 0.90: 0.83: 0.99. Pronotum densely and markedly punctate, with punctures merely connected with each other on median area of disc.

The population from Yongsheng County, Lijiang City (YsC in Figs. 13 , 16 , 17 , 18 ) is with darker pitch-black body color, clypeus more protruding anteriorly, with anterior margin more distinctly emarginate; antennae distinctly short, only reaching basal sixth of elytra, relative lengths of antennomeres: 0.73: 0.32: 1.00: 1.00: 1.16: 1.07: 1.07: 1.02: 1.00: 0.92: 0.95; OI = 53.9 in male, and 2.59 in female; pronotum straight or only weakly projecting in middle, anterior angles obtuse; elytral encircled segments of striae with distinctly connected punctures; intervals more wrinkled. One male has genae more strongly and roundly protruding laterally, and only weakly curved, shortened aedeagus.

The population from Manwan Town, Lincang City (MwT in Figs. 13 , 16 , 17 , 18 ) has clypeus more protruding anteriorly, with anterior margin more distinctly emarginate; antennae elongate, reaching basal fourth of elytra or slightly longer; relative lengths of antennomeres: 0.75: 0.34: 1.36: 1.28: 1.33: 1.36: 1.29: 1.19: 1.16: 1.11: 1.28; OI = 48.8–50.2 in male, and 2.57 in female; head and pronotum more glabrous, sparsely and finely punctate, punctures more distinct in small individuals; lateral margins evenly rounded. All legs with smaller and shallower punctures.

The population from Wuliang Mountain (WlM in Figs. 13 , 16 , 17 , 18 ) has clypeus more protruding anteriorly, with anterior margin more distinctly emarginate; antennae slightly longer, reaching basal 2/7 of elytra; relative lengths of antennomeres: 0.70: 0.38: 1.28: 1.16: 1.28: 1.26: 1.19: 1.16: 1.11: 1.00: 1.05; OI = 48.7–51.9 in male, 2.34 in female; genae less projecting anterolaterally; pronotum hexagonal, lateral margins buckled in middle, anterior angels bent ventrally, posterior angles vertical, somewhat projecting laterally; disc densely scattered shallow punctures.

The population from Ailao Mountain (AlM in Figs. 13 , 16 , 17 , 18 ) has clypeus more protruding anteriorly, with anterior margin more distinctly emarginate; antennae slightly shorter, reaching basal fifth of elytra, with each antennomeres notably shorter, relative lengths of antennomeres: 0.77: 0.42: 1.31: 1.26: 1.29: 1.26: 1.19: 1.11: 1.07: 0.99: 1.09; OI = 50, and 2.16 in female; pronotum densely and markedly punctate, posterior angles distinctly projecting laterally, more notebly constricted behind widest point in female; male possessing slightly wider protarsi; impressions of sternites III and IV with central swelling portions ridged.

Distribution. ( Map 1 , 2) CHINA: Yunnan.

Comparative notes. Morphostenophanes yunnanus resembles M. aenescens , see comparative notes of the latter.

Comments Morphostenophanes yunnanus is here defined to include a series of populations from several adjacent localities in central and eastern Yunnan. They are very similar in general appearance, including dark-grey body color, slender and moderately convex habitus, densely scattered elytral encircled segments of striae without pinkish luster (in most cases), male protibiae curved in apical third, with dorsal side of inner margin more concave than ventral one, and almost the same genital structures; but each slightly differs from each other in certain characters, e.g. length of antennae, cephalic and pronotal punctation. Comparison of any two populations may result in a subspecifice or even species level classification (e.g. specimens from Manwan Town and Jizu Mountain seems very different, with the former possessing wider head and pronotum, sparsely and finely punctate, antennae reaching basal fourth of elytra, while the latter possessing narrower head and pronotum, densely and coarsely punctate, antennae only reaching basal fifth of elytra). However, a comprehensive comparison of all the seven populations shows relatively continuous variability: individuals from south-central populations (Lincang, Wuliang Mountain, Ailao Mountain) bear less obvious cephalic and pronotal punctations, which is more pronounced in northeastern populations (Central Dali, Jizu Mountain, Eastern Binchuan, Lijiang City); length of antennae also successively becoming shorter from the west to the east.

In the present study, thirty specimens from Weibao Mountain were examined by the author, which showed considerable intrapopulation variations, especially in pronotal shapes. The pronotum of most individuals is barrelshaped with lateral margins roundly curved, inclined inwards anteriorly, and somewhat constricted before the base, but in few individuals, the lateral margins are more or less projecting at the widest point, which is similar to those of Wuliang Mountain population. Specimens from other localities were sparser but it is reasonable to believe that such intrapopulation variations also exist in those populations.

Specimen data and field observations show that M. yunnanus lives at elevations of 1900 to 2600 meters in central and eastern Yunnan. Such mountainous regions are spread all over this region and connected with each other. Similar general appearance among the above-mentioned seven populations suggest that all these populations spread to these mountains within a relatively short period of time, or relatively high rate of interpopulation gene flow were maintained. Therefore, it is inadequate to classify any of these populations as distinct subspecies or species. A mo- lecular analysis of with more specimens from this whole region is required to reveal exact relations among these populations.

Etymology. The new species is named after the province of its type locality.

Figures

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

FIGURE 12. Habitus of Morphostenophanes yunnanus Zhou new species (Central Dali Population, i.e., CDl) from Weibao Mountain. Male (A, C), and female (B, D); in dorsal (A, B), and lateral view (C, D). Scale bars = 5 mm.

FIGURE 13. Habitus of Morphostenophanes yunnanus of other populations, all male, in dorsal view. Distribution of M. yunnanus (Map 2). Habitats labelled, and full meaning of all abbreviations expounded as in Map 2. 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.