Miridiba (Miridiba) xingkei Gao & Fang, 2018

Gao, Chuan-Bu, Bai, Ming, Fang, Hong & Yu, Zhi-Guo, 2018, Four new species of the genus Miridiba Reitter (Coleoptera: Scarabaeidae: Melolonthinae) from China, Zootaxa 4527 (1), pp. 1-20 : 6-9

Miridiba (Miridiba) xingkei Gao & Fang , new species

( Figs. 3 , 6 )

Type locality. CHINA: Yunnan Province: Xishuangbanna City .

Type material examined. Holotype, male, labelled: “ Menga, Xishuangbanna, Yunnan / 1050–1180 m / Chinese Academy of Sciences [typeset, Chinese ] // 1958. V. 13 / Collector Pu Fuji [typeset, Chinese ] // Holotrichia (P.) ciliatipennis Moser ♂ / Designed by You-wei Zhang [handwritten, Chinese ] // HOLOTYPE ♂ / Miridiba xingkei sp. nov. / Chuanbu Gao & Hong Fang / det. 2018 [typeset, red label]”, deposited in IZCAS; paratype, female: “Jingdong, Yunnan 1200 m / 1957. IV. 29 / A. Monchadsky [typeset, Chinese and Russian] // PARATYPE ♀ / Miridiba xingkei sp. nov. / Chuanbu Gao & Hong Fang / det. 2018 [typeset, yellow label]”, deposited in IZCAS; paratype, male: “Jingdong 1170 m / 1956. V. 26 / Zagulyaev lamp [typeset, Chinese and Russian] // PARATYPE ♂ / Miridiba xingkei sp. nov. / Chuanbu Gao & Hong Fang / det. 2018 [typeset, yellow label]”, deposited in IZCAS; paratype, female: “Xiaomengyang, Yunnan 850 m / 1957. V. 3 / Qiuzhen Liang [typeset, Chinese and Russian] // Holotrichia (P.) ciliatipennis Moser ♀ / Identified by Youwei Zhang 1981. VI [handwritten, Chinese] // PARATYPE ♀ / Miridiba xingkei sp. nov. / Chuanbu Gao & Hong Fang / det. 2018 [typeset, yellow label]”, deposited in IZCAS; paratype, male: “Yun Jinghong, Xishuangbanna, Yunnan / 650 m / Chinese Academic of Sciences [typeset, Chinese] // 1959-?-5 / Collector Xuezhong Zhang [typeset] // H. ciliatipennis Moser / genitalia / 62.3.19 [handwritten] // Holotrichia ciliatipennis Moser / Identified by Youwei Zhang [handwritten, Chinese] // IOZ(E)1967842 [typeset] // PARATYPE ♂ / Miridiba xingkei sp. nov. / Chuanbu Gao & Hong Fang / det. 2018 [typeset, yellow label]”, deposited in IZCAS; paratype, male: “Yun Jinghong, Xishuangbanna, Yunnan / 650 m / Chinese Academic of Sciences [typeset, Chinese] // 1958-V-11 / Collector Xuewu Meng [typeset] // Holotrichia ciliatipennis Moser / Identified by Youwei Zhang [handwritten, Chinese] // IOZ(E)1967836 [typeset] // PARATYPE ♂ / Miridiba xingkei sp. nov. / Chuanbu Gao & Hong Fang / det. 2018 [typeset, yellow label]”, deposited in IZCAS; paratype, female: “Yunpenghun, Xishuangbanna, Yunnan / 1200- 1400 m / Chinese Academic of Sciences [typeset, Chinese] // 1958-V-11 / Collector Xuewu Meng [typeset] // PARATYPE ♀ / Miridiba xingkei sp. nov. / Chuanbu Gao & Hong Fang / det. 2018 [typeset, yellow label]”, deposited in IZCAS; paratypes, 3 females: “Jingdong, Yunnan 1200 m / 1957. IV. 25 / A. Monchadsky [typeset, Chinese and Russian] // PARATYPE ♀ / Miridiba xingkei sp. nov. / Chuanbu Gao & Hong Fang / det. 2018 [typeset, yellow label]”, deposited in IZCAS; paratype, female: “Simao, Yunnan 1300 m / 1957. V. 9 / Fuji Pu [typeset, Chinese and Russian] // PARATYPE / Miridiba xingkei sp. nov. / Chuanbu Gao & Hong Fang / det. 2018 [typeset, yellow label]”, deposited in IZCAS; paratype, male: “Jingdong 1170 m / 1956.?. 1 / Zagulyaev lamp [typeset, Chinese and Russian] // PARATYPE ♂ / Miridiba xingkei sp. nov. / Chuanbu Gao & Hong Fang / det. 2018 [typeset, yellow label]”, deposited in IZCAS; paratype, female: “ Yunnan Xishuangbanna Menghai / 1982-?- 16 / Wang Sumei, Zhou Jingruo [handwritten, Chinese] // C586 [handwritten] // PARATYPE ♀ / Miridiba xingkei sp. nov. / Chuanbu Gao & Hong Fang / det. 2018 [typeset, yellow label]”, deposited in NWAUF; paratypes, 2 females: “ Yunnan, Xishuangbanna, Menglong / Miridiba xingkei sp. nov. / Chuanbu Gao & Hong Fang / det. 2018 [typeset, yellow label]”, deposited in NWAUF

Description of holotype (male). Body length 22.8 mm; width across humeri 9.8 mm, oval-elongate, strongly convex, dorsal surface glabrous.

Colour: head, pronotum, scutellum and legs dark reddish brown; antennae, elytra and abdomen brown ( Figs. 3a, b ).

Head: Frons densely punctate and glabrous; clypeus arcuate shaped, apex weakly emarginate medially; anterior margin moderately reflexed; fronto-clypeal suture wave-shaped; frontal carina distinctly raised and nearly straight; clypeus shorter than frons, length ratio between clypeus and frons before carina 0.60; distance between eyes nearly four times wider than eye ( Fig. 3c ). Antenna with 9 antennomeres; club with 3 antennomeres, slightly longer than antennomeres 2-6 combined ( Fig. 3d ).

Thorax: Dorsal surface of pronotum densely punctate and glabrous, widest at basal 2/5; anterior margin smooth and flanged; lateral margin smooth and broadly reflexed; posterior margin smooth; anterolateral angles obtuse, posterior angles obtuse and round. Prosternal process basiconic shaped. Scutellum triangular, dorsal surface densely punctate and glabrous, 1.58 times wider than long. Dorsal surface of elytra glabrous, sutural costae developed; epipleuron with long, dense cilia ( Figs. 3a, b ).

Legs: Protibia tridentate, denticle 2 sharp; dorsal carina forking to denticle 2; apical spur of protibia sharp, apical spur reaching basal one half of protarsomere 1. Metafemora moderately covered with long soft hairs near anterior margin and rough setae near posterior margin ( Fig. 3b ); outside of metatibia with 1 completed carina at distal 2/5, carina arc-shaped; dorsolateral margin with 2 thorns; dorsomedial margin with 5 pubescent thorns small to large; metatibia with two apical spurs of different sizes, the big spur acinaciform, 1.72 times longer than the small spur ( Fig. 3e ); metatarsomere 1 equal in length to metatarsomere 2.

Abdomen: Lateral sides of abdominal sternites densely punctate and setiferous, setae short; posterior sternites 5 and 6 covered with long soft hairs.

Pygidium: Fan-shaped pygidium densely punctate and setiferous, 1.37 times wider than long, apical pygidium at a right angle; middle area weakly convex.

Male genitalia. Phallobase: Phallobase 1.2 times longer than parameres; dorsal surface with a depressed longitudinal sulcus at middle; anterior 1/5 of phallobase weakly constricted. Parameres: Parameres with two pairs of branches: two thick long dorsal branches and two short ventral branches; each dorsal branch with a thick protuberance on dorsum; tip of each dorsal branch with a notch in the ventral side; ventral branch with a big coneshaped hook ventrally before the apex ( Figs. 3 g–i). Endophallus: Dorsal endophallus with temones tapered; medial endophallus with small hooks; distal end of endophallus with a round seminal vesicle ( Fig. 3j ).

Female. Body slightly longer and broader than in male. Antenna with 9 antennomeres; club with 3 antennomeres, shorter than antennomeres 2–6 combined. Metafemora and apex of metatibia broader than in male. The big spur of apical metatibia broader and blunter than male, 1.3 times longer than the smaller spur ( Fig. 3f ).

Variability. All the paratypes slightly differ in size (total body length 21.7–25.6 mm, width across humeri 9.5– 11.6 mm).

Diagnosis. Miridiba (M.) xingkei new species and Miridiba (M.) ciliatipennis ( Moser, 1913) are similar in the elytral epipleuron bearing dense, long cilia. The two species can be separated by following characters: the presence or absence of the midline on the posterior of the pronotum (absent in M. (M.) xingkei new species; present in M. (M.) ciliatipennis ), the form of setae near the posterior margin of the metafemora (few large setae in M. (M.) xingkei new species, dense small setae in M. (M.) ciliatipennis ), the shape of the spurs of the apical metatibia (arcshaped in M. (M.) xingkei new species, straight in M. (M.) ciliatipennis ), the form of the parameres (each dorsal branch with a developed protuberance in M. (M.) xingkei new species, the dorsal branches without protuberances in M. (M.) ciliatipennis ).

Distribution. China (Yunnan: Puer, Xishuangbanna) ( Fig. 6 ).

Etymology. This new species is dedicated to Dr Xingke Yang, a respected researcher, who has devoted himself into taxonomy and systematics study of Chinese Coleoptera for more than thirty years. He will retire from the Institute of Zoology, Chinese Academy of Sciences in 2018.

Chinese name. 杨脊鳃金龟

Remarks. Chang (1964) listed M. (M.) ciliatipennis from China. However, we examined all specimens in IZCAS identified as M. (M.) ciliatipennis by Chang himself and they all belong to the new species M. (M.) xingkei . Based on this, we have excluded M. (M.) ciliatipennis from the Chinese fauna.

Figures

FIGURE 3. Miridiba (M.) xingkei Gao & Fang, new species, holotype. a, habitus, dorsal view; b, habitus, lateral view; c, head, dorsal view; d, antennae; e, apical spurs of metatibia, male; f, metatarsi, female; g, parameres, dorsal view; h, parameres, lateral view; i, parameres, ventral view; j, endophallus, dorsal view. Scale bar: 5 mm for a, b; 1 mm for c, d, e, f, g, h, i, j.

FIGURE 6. Distribution map for six Miridiba species in China.