Three new genera and five new species of the tribe Meconematini (Orthoptera: Tettigoniidae: Meconematinae) from Southwestern China

This paper deals with the brachypterous Meconematini, including three new genera, Acosmetides gen. nov., Neocyrtopsides gen. nov. and Macrocosmetura gen. nov. Five new species are described: Acosmetides peltates gen. et sp. nov., Acosmetides dilobosa gen. et sp. nov., Acosmetides platycerca gen. et sp. nov., Neocyrtopsides bispina gen. et sp. nov. and Macrocosmetura truncata gen. et sp. nov. Two new combinations are proposed: Acosmetides trigentis (Wang, Bian & Shi, 2016) gen. et comb. nov. and Neocyrtopsides platycata (Shi & Zheng, 1994) gen. et comb. nov.


Material and methods
The brachypterous Meconematini groups are fl ightless and restricted to narrow distribution areas. The type localities of the species described in this paper are distributed in Yunnan, Guizhou, Guangxi, Sichuan and Hunan, China.
The material was collected by us and the graduate students during the last two decades, and the type specimens of the new species are preserved in the Museum of Hebei University (HBU).
Morphological images were acquired using a Leica M205A digital imaging system. The following conventions were adopted for the specimen measurements: body = distance from apex of fastigium verticis to posterior margin of tenth abdominal tergite; pronotum = distance from anterior to posterior margin of pronotum; hind femur = distance from base of hind femur to apex of genicular lobe; ovipositor = distance from subgenital plate base to apex of ovipositor.

Diagnosis
The new genus resembles the genus Acosmetura Liu, 2000, but diff ers from it in the following characters: male tenth abdominal tergite protruded backwards with posterior margin split or concave; subgenital plate with basal area broad, apical area narrow, with a median lobe.

Etymology
The name of the new genus is derived from the genus name Acosmetura and the Greek ʻ-idesʼ, meaning ʻalikeʼ. The Chinese name of the genus is 拟异饰尾螽属 (Ni Yi Shi Wei Zhong Shu).

Diagnosis
The new species is similar to its congeners in appearance, but diff ers from them in male genitalia, subgenital plate and tenth abdominal tergite.

Etymology
The name of the new species refers to the morphology of the male genitalia, the Greek ʻpeltate-ʼ meaning ʻshield-shapedʼ.

B
. Small and stout.

T
. Pronotum protruded backwards, reaching posterior margin of fi rst abdominal tergite, or anterior margin of second abdominal tergite; anterior margin roughly straight, posterior margin rounded; hind transverse sulcus distinct; lateral lobe longer than deep, posterior margin tapering; humeral sinus absent. Thoracic auditory spiracle exposed, small and oval.
L . All femora unarmed on ventral surfaces. Fore coxa with a spine; fore tibia with 5 medium long symmetrically arranged spines on both sides of ventral surface, tibial tympana open and oval on both sides. Middle tibia with 4-5 spines on inner and outer margins of ventral surface. Hind femur with apices of knees obtuse; hind tibia with 22-24 spines on inner and outer margins of dorsal surface, bearing 2 pairs of ventral apical spurs and 1 pair of dorsal apical spurs.

M
. Ninth abdominal tergite with lateral margin slightly broadened backwards. Tenth abdominal tergite narrow, posterior margin of middle area protruded backwards, apical area with median sulcus, which splits. Cercus with base cylindrical, middle area concave downwards, apex upcurved, twisted, inner edge ridge-shaped, apex indistinctly tooth-shaped. Genitalia sclerotized, shield-shaped, broad, terminal papillary. Subgenital plate with base broad, basal margin concave triangularly; apical half narrow, only with a median lobe, moderately upcurved, apex with small spine-shaped process on the middle. Styli short, conical, apices rounded, inserted on lateral margins near apical one third of subgenital plate.

F
. Pronotum shorter than in male. Tegmina short, most covered by pronotum. Cerci long conical, apices subacute. Subgenital plate with base broad, ventral surface of which with a colliculus process; lateral margins tapering, posterior margin slightly concave. Ovipositor moderately upcurved with fi nely serrated dorsal and ventral margins along entire length, apex acute.

C
. Body yellowish brown, with admixed brown spots, some area light green when alive. Head with dorsum brown, eyes brown. Disc of pronotum with longitudinal brown stripe, which bifurcates in metazona, other area of which is light. All tarsi light brown, spines on all tibiae brown. Outer surface of hind femur with some parallel light brown spots, hind knees brown, apex of hind tibia brown. Lateral surface of abdomen brown.

Remarks
In some populations, lateral lobes of pronotum with ventral edge brown. The middle lobe of male subgenital plate with a pair of indistinct small spines on lateral sides of subapex.

Diagnosis
The new species resembles Acosmetides peltates gen. et sp. nov., but di ff ers from it in male tenth abdominal tergite and genitalia.

Etymology
The name of the new species refers to the morphology of the tenth abdominal tergite in males, the posterior part of which has a pair of lateral lobes. Greek ʻdi-ʼ means with ʻtwoʼ and ʻlobosʼ means ʻlobeʼ.
L . All femora unarmed on ventral surfaces. Fore coxa with a spine; fore tibia with 5 medium long spines on inner and outer sides of ventral surface, tibial tympana open and oval on both sides. Middle tibia with 5-6 spines on inner and outer margins of ventral surface. Hind tibia with 24-27 spines on each side of dorsal surface, bearing 2 pairs of ventral apical spurs and 1 pair of dorsal apical spurs.
M . Ninth abdominal tergite with lateral areas slightly expanded backwards. Tenth a bdominal tergite extended backwards, with a U-shaped notch at the middle of posterior margin, divided into two lateral lobes, apices subacute. Genitalia sclerotized, base broad, other area very narrow, apex bifurcated. Cercus with base cylindrical, dorsal surface of middle area concave downwards, apical area upcurved, slightly twisted, inner margin ridge-shaped, apex rounded. Subgenital plate with base broad, terminal half conical, apex rounded. Styli long conical, apices obtuse, inserted on lateral margins near middle area of subgenital plate.

Diagnosis
The new species is similar to its congeners in appearance, but diff ers from them in m ale cerci and genitalia.

Etymology
The name of the new species is derived from the Latin ʻplaty-ʼ, meaning ʻbroadenedʼ, and ʻcerc-ʼ, meaning ʻcercusʼ. The Chinese name of the species is 宽尾拟异饰尾螽 (Kuang Wei Ni Yi Shi Wei Zhong). H . Frons slightly sloping backwards. Fastigium verticis conical, apex rounded with longitudinal sulcus on dorsum. Apical segment of maxillary palpus longer than subapical one, apical area infl ated, apex truncate. Eyes globular, protruded forwards.
L . All femora unarmed on ventral surfaces. Fore coxa with spine; fore tibia with 5 medium long spines on each side of ventral surface, tibial tympana open and ovoid on both sides. Hind femur with genicular lobes rounded; hind tibia with 24-26 spines on each side of dorsal surface, bearing 2 pairs of ventral apical spurs and 1 pair of dorsal apical spurs. M . Ninth abdominal tergite with lateral surface slightly broadened backwards. Tenth abdominal tergite wit h base half broad, apical half tapering, with a triangular notch on the middle of posterior margin, divided into two lateral lobes with apices rounded. Cercus with base thin, middle area widened, with a semiglobular concavity; apical area thin, apices incurved. Genitalia sclerotized, base area with circular lateral process on each side; middle area broadened, lamellate, near apex shrunk, subapex slightly broadened, apex roughtly truncate. Subgenital plate with basal area rectangular, apical area triangular, apex rounded. Styli long with apices rounded, inserted on lateral margins near apical one third.
C . Body light yellowish brown, with admixed brown spots. Dorsum of head brown, frons with 1 pair of longitud inal brown stripes, scapus and pedicel of antenna brown. Disc of pronotum with longitudinal brown stripe at prozona, which bifurcates into two bran ches at metazona, most of which is light; lateral lobe light, with brown stripe on ventral edge. All spines on tibiae brown. Abdomen brown, tenth abdominal tergite with apex light. Cerci brown, apices blackish brown. Styli light.

Remarks
The original description of the species is exact and the fi gure is clear (Wang P. et al. 2016). Based on the male tenth abdominal tergite with a notch in the middle of the posterior margin and the middle lobe of the subgenital plate distinct, the species should belong to the genus Acosmetides gen. nov.

Note
The Chinese name of the species is 三突拟异饰尾螽 (San Tu Ni Yi Shi Wei Zhong).

Diagnosis
The new genus is similar to Neocyrtopsis Liu & Zhang, 2007, but diff ers from it in the following characters: male tenth abdominal tergite extended backwards, divided into two lateral lobes with apices obtuse, which fuse with epiproct, with rectangular notch between lobes; genitalia sclerotized, long, exposed. Male subgenital plate with middle lobe; styli inserted on lateral margins near middle of subgenital plate.

Etymology
The name of the new genus is derived from the genus name Neocyrtopsis, and the Greek ʻ-idesʼ, meaning ʻalikeʼ. The Chinese name of the genus is 拟新刺膝螽属 (Ni Xin Ci Xi Zhong Shu).

Generic characters
Body small, robust. Frons slightly sloping backwards, fastigium verticis conical, terminal obtuse, furrowed dorsally. Apical segment of maxillary palpus longer than subapical one, apical area infl ated, apex truncate. Eyes globular, protruded forwards. Pronotum short, posterior area of lateral lobes tapering. Tibial tympana open and ovoid on both sides; genicular lobes of hind femora with apices rounded. Male tenth abdominal tergite elongated backwards and curved down, divided into 1 pair of lateral lobes with apices rounded; posterior margin fused with epiproct, after which with a rectangular notch; genitalia sclerotized, long, exposed; subgenital plate with basal area broad, terminal narrow, only with a middle lobe; styli inserted on lateral margins near the middle of subgenital plate.

Diagnosis
The new species is similar to Neocyrtopsides platycata (Shi & Zheng, 1994) gen. et comb. nov., but diff ers from it in m ale genitalia and subgenital plate.

Etymology
The name of the new species refers to the morphology of the male genitalia, the Latin ʻbi-ʼ meaning ʻa pairʼ and ʻspin-ʼ meaning ʻspine-shapedʼ. The Chinese name of the species is 双刺拟新刺膝螽 (Shuang Ci Ni Xin Ci Xi Zhong). Paratype CHINA • 1 ♀; same collection data as for holotype; HBU.

B
. Small and stout.

T
. Pronotum short, anterior margin roughly straight, posterior margin rounded; lateral lobes longer than deep, with posterior area tapering; hume ral sinus absent. Thoracic auditory spiracle exposed, small, elliptic. T . Tegmina short, mostly concealed beneath pronotum, only narrow edge visible. Hind wings absent.
L . All femora unarmed on ventral surfaces. Fore coxa with spine; fore tibia with 5 spines on inner side and 4 spines on outer side of ventral surface ; tibial tympana open and oval on both sides. Middle tibia with 4 short spines on each side of ventral surface. Hind tibia with 15-17 spines on each side of dorsal surface, bearing 2 pairs of ventral apical spurs and 1 pair of dorsal apical spurs.

M
. Ninth abdominal tergite slightly protruded backwards. Tenth abdominal tergite extended backwards, posterior area divided into 2 lateral lobe s, apices broadened, posterior area fused with epiproct, after which is a rectangular concavity. Cercus cylindrical, lightly incurved, base slightly stout, apex tooth- shaped. Genitalia sclerotized, dorsal branch narrow, near middle leaf-shaped expanded, lateral margins of apical half parallel, apex bispinose; ventral branch stout with apex thin (Fig. 4D). Subgenital plate with basal half broad, apical half narrow, lateral margins parallel, apex with a pair of spine-shaped processes, moderately upcurved. Styli long, inserted near base of middle lobe.

C
. Body yellowish brown, with admixed brown spots. Dorsum of head brown. Pronotum with 1 pair of small brown spots on metazona, lateral lobes blackish brown. Ninth to tenth abdominal tergites dark brown. Cercus brown, apical area of subgenital plate and genitalia dark brown. Spines on all tibiae brown.

Remarks
The species was described by Shi & Zheng (1994) on the basis of a single specimen (holotype) collected in Emeishan (Sichuan). Later, in 2011, we collected many specimens of the species from the type locality. Wang H.J. et al. (2013) determined the species should be placed in the genus Neocyrtopsis Liu & Zhang, 2007 because of the morphology of the male tenth abdominal tergite and genitalia. However, after the species Neocyrtopsides bispina gen. et sp. nov. was discovered, it should be placed in the new genus because they diff er from the genus Neocyrtopsis in the male epiproct, the tenth abdominal tergite, the genitalia and the subgenital plate morphology. The species was suffi ciently described (see Wang H.J. et al. 2013).

Note
The Chinese name of the species is 宽板拟新刺膝螽 (Kuang Ban Ni Xin Ci Xi Zhong).

Diagnosis
The new genus resembles the genus Acosmetides gen. nov., but diff ers from it in the following characters: male and female ninth abdominal tergite markedly elongated ventrally, and tenth abdominal tergite extended backwards in both sexes with a concavity in the middle of the posterior margin.

Etymology
The name of the new genus is derived from the Greek ʻmacr-ʼ, meaning ʻlargeʼ or ʻlongʼ, and the genus name Cosmetura. The Chinese name of the genus is 大饰尾螽属 (Da Shi Wei Zhong Shu).

Generic characters
Body small, robust, comparatively large for the related genera. Fastigium verticis conical, apex rounded, furrowed dorsally. Eyes globular. Apical segment of maxillary palpus longer than subapical one, apical area infl ated, apex truncate. Pronotum elongated backwards, posterior area of lateral lobe tapering. Ninth abdominal tergite with lateral surfaces protruding ventrally, apices fi nger-shaped; tenth abdominal tergite expanded backwards. Male genitalia sclerotized; subgenital plate with basal half broad, apical half with middle lobe and short paired lateral lobes.

Diagnosis
Male tenth abdominal tergite observably extended backwards and genitalia sclerotized, posterior area broad, apex truncate.

Etymology
The name of the new species refers to the morphology of the male genitalia, the word ʻtruncataʼ from the English ʻtruncateʼ. The Chinese name of the species is 截形大饰尾螽 (Jie Xing Da Shi Wei Zhong). . Small and stout.

T
. Pronotum longer, posterior margin reaching anterior margin of third abdominal tergite; lateral lobe longer than deep, with posterior margin tapering. Thoracic auditory spiracle exposed, small, oval.
L . All femora unarmed on ventral surfaces. Fore coxa with spine; fore tibia with 5 spines on inner margin and 5 spines on outer margin of ventral surface, tibial tympana open and oval on both sides. Middle tibia with 4-5 spines on each side of ventral surface. Hind tibia with 20-23 spines on each side of dorsal margin, 2 pairs of ventral apical spurs and 1 pair of dorsal apical spurs. Thoracic auditory spiracle exposed, small, elliptic.

M
. Ninth abdominal tergite expanded backwards, postero-lateral corner elongated, fi ngershaped, incurved, apical area curved backwards and outwards, apex rounded. Tenth abdominal tergite extended backwards, basal half broad, apical half narrow, with a median split, divided into 2 square lateral lobes. Cercus short, apical half downcurved, covered by tenth abdominal tergite, not visible in dorsal view. Genitalia sclerotized, posterior area broad, truncate (Fig. 5I). Subgenital plate with basal half broad, apical half with long middle lobe and 1 pair of short lateral lobes. Styli long inserted on inner margins of subapical areas of the lateral lobes.

C
. Body light yellowish brown. Dorsum of head with 3 longitudinal brown stripes. Pronotum with disc light, and 1 pair of brown spots; lateral lobe with ventral edge brown. Outer surface of hind femur with some light brown spots, knee area brown, spines on all tibiae brown. Ninth to tenth abdominal tergites brown.

Discussion
The species diversity of the brachypterous Meconematini in China is extremely high, and the number of new taxa is still increasing (Wang T. et al. 2019a). Due to the reduced tegmina, the dispersal ability of these species is limited, indicating they occur in a restricted region. In China, thanks to the suitable climate conditions, the species of this tribe are mainly distributed in the Oriental region, with most of them being endemic (Wang T. et al. 2020c).
The new species described in this article are mainly distributed in valleys; due to geographic isolation and climate factors, the distributions of these taxa is gradually shrinking, and fi nally they are only distributed in valleys. As the distribution area shrinks, the dispersal ability of these taxa may decrease, consequently the body becomes smaller and tegmina degrade only for communication.
However, as the number of new species continues to grow, some problems arise, such as how to defi ne the genera / species boundaries. Morphologically, some genera (such as Sinocyrtaspis Liu, 2000 andParacosmetura Liu, 2000) are very similar and diff er from each other by only one or two morphological characteristics (male pronotum or tenth abdominal tergite). Is this enough for distinguishing diff erent genera? Fortunately, an integrative taxonomy could shed a bright light for those of us attempting to answer the relevant questions (such as Hemp & Heller 2017;Hemp et al. 2018).