﻿Taxonomic review of Manocoreini with description of a new species from China (Hemiptera, Heteroptera, Coreidae)

﻿Abstract In the present paper, all seven species of Manocoreini are reviewed, and a new species Manocoreushsiaoisp. nov. is described from Guangxi, China. Photographs of habitus of all species, and detailed structures of the new species and type species of Manocoreus Hsiao, 1964 are provided. All species of Manocoreini of the world are keyed. A distribution map of all species is also provided.


Introduction
The tribe Manocoreini Hsiao, 1964 is a small group of Coreinae Leach, 1815, which only comprises the genus Manocoreus Hsiao, 1964, endemic to China (Li 1996. Hsiao (1964) described Manocoreus and four species from southern China as belonging to it: the type species M. vulgaris from Fujian, Guangdong, Jiangxi, and Zhejiang; M. marginatus from Yunnan; M. montanus from Sichuan; and M. yunnanensis from Yunnan. Ren (1983) provided brief notes on all four known species of Manocoreus and described M. astinus from Yunnan. Ren (1993) described M. grypidus from Hubei, while Liu and Ren (1993) described M. furcatus from Fujian. Up to now, the genus Manocoreus contains seven species, and all of which are only found in southern China.
Tribe Manocoreini was established based on characteristics of head and plica on abdominal sternite VII of female, and was considered as closely related to Dasynini Bergroth, 1913and Gonocerini Mulsant & Rey, 1870(Hsiao 1964. Li (1996Li ( , 1997 published the comparative morphological and cladistic analysis of Coreidae, his result supported Manocoreini as a taxon of tribal rank. Upon examination of Manocoreini collections from China, Manocoreus is reviewed, and a new species Manocoreus hsiaoi sp. nov. is described from Guangxi province, China.

Materials and methods
External structures were examined by using a Zeiss Discovery V20 stereomicroscope. Measurements (in mm) were taken using Zeiss ZEN 2.5 pro software.
The male genital capsule and female abdomen were removed in dry condition and soaked in 75 °C, 10% KOH for 30 minutes to one hour to remove muscles. Endosoma was carefully stretched with a pair of forceps under a Zeiss Discovery V20 stereomicroscope. Photographs of habitus and detailed structures were taken by using a Canon EOS 7D Mark II camera equipped with a LAOWA 100 mm F2.8 macro 2× macro lens. Photographs of the genitalic structures were taken using a Canon EOS 7D Mark II camera equipped with a LAOWA 25 mm F2.8 macro 2.5-5× macro lens, or equipped with a tube lens and a Mitutoyo M Plan Apo 10× objective lens. Morphological terminology follows Hsiao (1964), Ren (1993), Brailovsky (2007a, b), Yi and Bu (2015), Zhou and Rédei (2020), and Pluot-Sigwalt and Moulet (2020).
Abbreviations used in the text and figures are as follows: valvifers VIII, IX.
Label data of type specimens were cited verbatim: a slash (/) separates the lines and a double slash (//) different labels from the same specimen; notes about the label data were indicated in square brackets ([]).
Abbreviations for depositories:

IZCAS
Institute of Zoology, Chinese Academy of Sciences, Beijing, China; NKUM Institute of Entomology, Nankai University, Tianjin, China; SYSBM Museum of Biology, Sun Yat-sen University, Guangzhou, China.
Distribution Description. Body elongate, ~ 3.76-3.94× as long as humeral width (Fig. 3A-D). Color, integument, and vestiture. Body brownish yellow, dorsum of head with dense black punctures, underside of head with dense punctures concolorous with body surface (Fig. 4B), compound eyes dark red, ocelli reddish; labium yellow, distal one fourth of segment IV black; antennomeres I-III brownish yellow, antennomere IV paler, apical portion of antennomeres II and III blackish, antennomere I with moderately dense small black tubercles, small tubercles on antennomeres II and III more scattered and paler, each segments with short semi-erect setae; lateral margin of pronotum black (Fig. 4A); collar, callus area, area near lateral margin and posterior margin with black punctures, central discal region of pronotum with yellow punctures; propleura and prosternum yellow, propleura with black punctures (Fig. 4C); scutellum and corium brownish yellow, with brown to black punctures, meso-and metapleura, and mesoand metasternal yellow, meso-and metapleura with black punctures; legs yellow, only apical area of tarsal segment III blackish brown, femora and tibiae of each leg with moderately dense small brownish tubercles, femora, tibiae and tarsi of each leg with short semi-erect setae, setae on apical half of tibiae and tarsi denser; corium with a large and more or less central black spot, membrane grey, basal area darker; middle and apical portion of connexivum of each segment black, venter of abdomen yellowish brown, abdominal terga with a median black spot on each side of segments II-VII; a pair of smaller black spots located near anterior margin of segments III to VII (Fig. 3).
surpassing posterior margin of mesocoxae, not reaching to anterior margin of metacoxae. Pronotum ~ 1.43-1.60× as width across humeral angles as its median length; scutellum ~ 0.96-1.16× as long as its width. Anterior peritreme of metathoracic scent gland slightly larger than protruding posterior peritreme, gyrification of evaporatorium deep (Fig. 4C, D). Pregenital abdomen. Abdomen oblong, spiracles situated near lateral margin of abdominal sterna III-VII (segments III to VIII in female), before middle line of each segment; sternum VII of male strongly concave medially, length of concave part ~ 1/2 length of sternum VIII in ventral view; in female plica triangular, and partly exposed out of sternum VI, posterior margin of sternum VII sinuated. External male genitalia. Genital capsule opening dorsally (Fig. 4E, F), dorsoposterior rim wide, median projection conspicuous, triangular (Fig. 5D: mdp), posterior margin of genital capsule broadly sinuate and ventroposterior process median (Fig. 5D: mvp), lateral portion of posterior margin roundly produced on each side (Fig. 5D)  Etymology. This specific epithet is dedicated to the memory of Prof. Hsiao Tsai-Yu (1903-1978, founder of the modern Heteroptera research in China (Zheng et al. 1979).
Distribution. China. Guizhou: Daozhen (Zhu and Bu 2005); Yunnan: Xishuangbanna (Fig. 16). Remarks. This species can be recognized from all other species of Manocoreus by the following characteristics: antennomere III dilated apically; lateroventral side of the head, thorax, and abdomen with wide, dark reddish to brownish longitudinal stripe (Fig. 7E); lateral process on posterior margin of genital capsule round (Fig. 14F).

Discussion
According to the only cladistic analysis based on morphological data which included Manocoreini, Manocoreini was the sister group of Gonocerini (Li 1997). Based on our examinations of specimens of these two tribes, Manocoreini has the following characteristics that are significantly different from the latter: (1) head with a small dentate or plate-like process in front of antenniferous tubercles, whereas without such process in Gonocerini; (2) plica of female sternum VII with triangular, or rectangular depression, covered by sternum VI, whereas the posterior margin of plica depressed and near the anterior margin of sternum VII in Gonocerini; (3) genital capsule has median ventroposterior process, whereas the posterior margin of genital capsule concave in Gonocerini; (4) basiconjunctivum moderately sclerotized, whereas strongly sclerotized in Gonocerini. According to recent seminal research on the morphology of spermatheca in Coreidae (Pluot-Sigwalt and Moulet 2020), the spermatheca of coreids was divided into three types (I, II, III), and type III could be subdivided into four subtypes (A, B, C, D). Based on our study, the spermatheca of Manocoreini belongs to type III, subtype A, and is closely related to Dasynini, Gonocerini, and Homoeocerini. Some recent molecular phylogenetic studies show that Manocoreini is closely related to Dasynini, Homoeocerini, Mictini, and Coreini (Ye et al. 2022) or Gonocerini and Coreini (Tian et al. 2023). Although Manocoreini can be clearly distinguished morphologically, their phylogenetic relationship still needs to be further verified by adding more molecular and biological evidences.
In the genus Manocoreus, M. marginatus and M. yunnanensis are closer in morphology than other species, such as having slender antenna (Figs 7A, B, 8D-F), posterior margin of male sternum VII concave ~ 1/3 in ventral view (Fig. 13E, H), and middle of female sternum VII sharply concave, both sides with process backward (Fig. 14E, H). More morphological and molecular evidences are needed to figure out the phylogenetic relationship and phylogeographical pattern of the species in this genus.