Cylindroeme shii, Wang & Xie & Wang, 2022

Wang, Yingqi, Xie, Guanglin & Wang, Wenkai, 2022, A revision of the genus Cylindroeme Vives (Coleoptera, Cerambycidae, Cerambycinae), ZooKeys 1082, pp. 127-134 : 127

Cylindroeme shii sp. nov.

石氏扁柱胸天牛 Figures 3-8 , 10-11 , 13-21 , 22-24

Type material.

Holotype: male, China: Qinghai, Qilian County, Babao town (八宝镇), Ice Valley (Bing gou, 冰沟), 3110 m, 38°7'60"N, 100°10'21"E, July 25, 2019, leg. Guanglin Xie. Paratypes: 7 males and 1 female, the same as holotype data; 3 males and 3 females, Qinghai, Qilian County, A’rou Township (阿柔乡), Deerhorn Valley (Lujiao Gou, 鹿角沟), 3020 m, 38°8'20"N, 100°24'15"E, July 20, 2019, leg. Guanglin Xie; 5 males, Qinghai, Qilian County, A’rou Township (阿柔乡), Deerhorn Valley (Lujiao Gou, 鹿角沟), 3020 m, 38°8'20"N, 100°24'15"E, July 22, 2019, leg. Guanglin Xie. All of the type specimens are deposited in the Entomological Museum, Yangtze University, Jingzhou, Hubei, China, except for two male paratypes in the private collection of Chen Mou (Shanghai, China) and one male paratype in the private collection of Tianlong He (Anhui, China).

Description.

Male, body length 8.0-11.0 mm, humeral width 1.5-2.0 mm. Body mostly yellowish brown to light chestnut-brown, clothed with yellowish silky pubescence. Head slightly darker, mandible black apically, clothed with yellowish hairs on outside; labrum and apex of clypeus pale yellow. Antennae sometimes lighter in colour towards to end, fringed with sparse yellowish hairs on inner side of basal segments, more conspicuous on antennomeres III and IV. Pronotum with pubescence obviously silky, forming a squared area on anterior half that looks distinctly different in appearance due to the different direction of the pubescence. Elytra with semirecumbent pubescence. Abdomen with apical ventrite yellowish. Legs with tarsi wholly or only apically yellowish and claw wholly yellowish.

Head about as broad as pronotum, subparallel-sided behind eyes; frons short, subrectangular, with a longitudinal median sulcus; eyes large, upper lobes widely separated; genae very short. Antennae slightly shorter than body, antennomere III slightly longer than antennomere IV, antennomeres V-XI gradually shortened in length. Pronotum longer than broad, broadest behind middle; disc with three narrow longitudinal indentations at apex, median one relatively short, located before the middle, lateral two relatively long, exceeding the middle backwards; with two oblique fine longitudinal ridges at base, anterior ends connected behind the median indentation, forming an inverted V-shaped structure, enclosing a quite flat triangular area. Scutellum ligulate, with distinct edge. Elytra elongate, about 4.2 times as long as humeral width; humeri rounded, slightly protruding forward; sides subparallel; apex rounded; disc finely punctate, with an inconspicuous longitudinal rib at the middle of each elytron, not reaching the apex. Prosternum finely transversely wrinkled apically, mesosternum transverse, metasternum longer than wide, with a longitudinal median indentation at posterior half, pro- and mesosternal intercoxal processes nearly absent. Abdomen cylindrical, distinctly narrower than metathorax, first abdomere obviously longer than others. Legs short, femora strongly widened, laterally flattened, metafemur distinctly exceeding ventrite II, first metatarsomere about 1.4 times as long as next two combined, claws divaricate.

Male genitalia. About apical half of tergite and sternite VIII clothed with sparse setae, longer on sides, apical edge of ventrite VIII more broadly transverse-truncate than tergite VIII. Tegmen waved in lateral view, parameres fused, converged towards apex; apex slightly truncate and sparsely setiferous; ringed part quite rounded, with lateral arms converged into a long median stem; relative length ratios of paramere, vertical diameter of ringed part (except median stem) and median stem equal to 4.84:7.22:6.41. Median lobe wide and short, relative length ratios of median lobe and median struts about 1:3, dorsal apex nearly straight, ventral apex mastoid. Endophallus with two arched basal sclerites connected together.

Female. Body length 9.0-10.5 mm, humeral width 1.6-2.0 mm. Similar to male but body colour a little lighter, antennae only reaching behind middle of body, pronotum nearly as long as broad, anterior lateral indentations and posterior longitudinal ridges less obvious than in the male, elytra about 4.3 times as long as humeral width, abdomen with five visible abdomeres, legs slightly shorter, metafemur reaching to about end of second abdomere.

Remarks.

The new species can be easily distinguished from the type species, Cylindroeme vietnamica , by the wider spacing of the upper eye lobes, shorter antennae, less elongate pronotum and elytra, and different discal structure of pronotum.

In the new species, the distance between the upper eye lobes is about as wide as the transverse diameter of a single upper eye lobe (Figs 10 , 11 , 13 ), while the upper eye lobes are almost connected in C. vietnamica (Figs 9 , 12 ); the male antennomere VIII about reaches to the apical two fifths of the elytra (Figs 3-6 ), while it nearly extends to the apical one tenth in C. vietnamica (Figs 1 , 2 ); the length-width ratio of male pronotum and elytra is about 1.1 and 4.2, respectively (Figs 3-6 ), while it is about 1.4 and 5.0 in C. vietnamica (Figs 1 , 2 ); the pronotum is without a remarkable V-shaped median depression at apex (Figs 10 , 11 , 13 ), while it is equipped with a remarkable, broad and short median depression with a V-shaped raised edge in C. vietnamica (Figs 9 , 12 ); the male pronotum is equipped with a distinct narrow longitudinal indentation at the apex, extending backwards to the middle and jointed with an inverted V-shaped ridge with two short lateral arms (Figs 10 , 11 ), while the apical median indentation is rather short, inverted triangular, and both lateral arms of the inverted V-shaped ridge are quite long in C. vietnamica (Fig. 9 ).

Etymology.

The new species is named after Professor Dr. Fuming Shi (Hebei University, China), a famous Chinese katydid taxonomist.

Distribution.

China (Qinghai).

Biological notes.

The adults of Cylindroeme shii sp. nov. were found on trunks of Picea crassifolia Komarov (Qinghai spruce). They were attracted by half-dead trees whose trunks were bored by xylophagous insects or damaged by other animals. The adults were found crawling and mating on these damaged tree trunks. Based on this, it can be speculated that Qinghai spruce ( Picea crassifolia ) should be its host plant.

The adults were first discovered on July 20, 2019. At the same time, one egg-laying female adult and one free-moving male adult of Necydalis inermis Pu, 1992 ( Cerambycidae , Necydalinae ) and the free-moving adults of Tetropium castaneum (Linnaeus, 1758) ( Cerambycidae , Spondylidinae ) were also found on Qinghai spruce. However, two year later, when the second author visited the same place again on 1-3 August, 2021, no individuals of the new species were found. It indicated that the adults of the new species may be active till the end of July at the latest.

Figures

Figures 1 - 8. Habitus of Cylindroeme spp. 1 - 2 Cylindroeme vietnamica Vives 3 - 8 Cylindroeme shii sp. nov. 1 - 2, 5 - 6 holotypes 3 - 4, 7 - 8 paratypes 1 - 6 male 7 - 8 female.

Figures 9 - 21. Habitus of Cylindroeme spp. 9 - 13 head and pronotum 14 - 21 male genitalia 9, 12 Cylindroeme vietnamica Vives 10 - 11, 13 - 21 Cylindroeme shii sp. nov. 9 - 10 holotypes 11 - 13 paratypes 9 - 11 male 12 - 13 female 14 - 15 abdominal segments VIII-IX 16 - 18 tegmen 19 - 21 median lobe 14, 16, 20 dorsal view 15, 17, 21 ventral view 18 - 19 lateral view Scale: 0.5 mm.

Figures 22 - 24. Living adults of Cylindroeme shii sp. nov. 22 - 23 male 24 mating pair, lateral view.