Five new species of Meta Koch, 1836 (Araneae: Tetragnathidae) from Gaoligong Mountains, China

Five new species of the genus Meta C.L. Koch, 1836 from the Gongligong Mountains, Yunnan are described: Meta hamata sp. nov. (♂♀), M. longlingensis sp. nov. (♂), M. tangi sp. nov. (♂♀), M. yani sp. nov. (♂♀) and M. yinae sp. nov. (♂♀). Detailed descriptions of somatic features and genitalic characters, photos of the body and genital organs, line drawings of the copulatory organs and distribution maps are provided.


Introduction
The Gaoligong Mountains, located in western Yunnan, are a sub-range of the Hengduan Mountains with steep slopes, ranging in altitude from 645 to 4640 m. They form a spectacular vertical natural landscape and have a wide variety of climates. They cover a total area of 111 000 km 2 that is considered a part of the Indo-Burmese biodiversity hotspot (Li et al. 2000;Myers et al. 2000). The diversity of spiders in the Gaoligong Mountains is very high. Seven new species of the genus Wolongia Zhu et al., 1997 and one new species of the genus Leucauge White, 1841 (Tetragnathidae) were reported by Wan & Peng (2013a, 2013b; Wang et al. (2009Wang et al. ( , 2010 mentioned 71 species of Coelotinae (Agelenidae), 30 of which were new to science; Miller et al. (2009) described 36 new species of Symphytognathoidea. All these were added to the many endemic spider species that had already been reported in the last twenty years Yin et al. 2002Yin et al. , 2003aYin et al. , 2003bYin et al. , 2009Xu et al. 2002).
The spider genus Meta C.L. Koch contains 24 species distributed worldwide (World Spider Catalog 2020), including fi ve from China (Li & Lin 2016): Meta mixta O. P.-Cambridge, 1885; M. nebulosa Schenkel, 1936;M. nigridorsalis Tanikawa, 1994;M. qianshanensis Zhu & Zhu, 1983;and M. shenae Zhu et al., 2003. M. nebulosa has not been reported again since it was described from a juvenile holotype by Schenkel (1936). Spiders of the genus Meta live mainly in the gullies of shady woods or in shallow caves, where they make fl at webs and situate themselves in the center of the web. While examining the specimens collected from Gaoligong Mountains, fi ve new species of the genus Meta were recognized and are described here.

Material and methods
All specimens were preserved in 75% ethanol and examined, illustrated, photographed and measured using a Leica M205C stereo microscope equipped with a drawing tube, a Leica MC170 camera and LAS software (Ver. 4.8). Male palps and female epigynes were examined and illustrated after being dissected. Female genitalia were cleared in 90% lactic acid. Eye sizes were measured as the maximum dorsal diameter. Leg measurements are shown as: total length (femur, patella and tibia, metatarsus, tarsus

Variation
The total length in male specimens examined ranges from 3.60 to 4.06, in female specimens from 4.26 to 4.90.
STERNUM. Brown, scutellate, with sparse brown hairs.  DORSUM. With two pairs of sigillae, yellowish brown, proximally with a white band followed by irregular black markings posteriorly (Fig. 1I). Venter of opisthosoma yellowish brown, with black markings. Dorsum of prosoma yellowish brown, with longitudinal dark brown band (Fig. 1I).
EMBOLUS. Long, distal portion needle-shaped, extending forward. Conductor longer than wide, slightly curved, arising meso-retrolaterally from bulb and extending clockwise, with a membranous end.

Female
Unknown.

Etymology
The specifi c name is a patronym dedicated to Mr. Guo Tang, one of the collectors of the type specimens.

Variation
The total length in male specimens examined ranges from 4.82 to 5.33, in female specimens from 5.50 to 6.67.

Variation
The total length in male specimens examined ranges from 4.11 to 4.56, in female specimens from 3.57 to 4.34.

Etymology
The specifi c epithet is taken from the family name of Prof. Changmin Yin, in honour of her great contribution to Chinese arachnology; noun. OPISTHOSOMA. Oval, dorsum with two pairs of sigillae, yellowish brown, with several irregular black markings (Fig. 1G). Venter of opisthosoma yellowish brown, with black markings. PALP (Figs 13, 15A-C). Cymbial ectobasal process Y-shaped, with hook-shaped tip. Paracymbium strong and rod-like, with sparse long, brown hairs. Metaine embolic apophysis longer than wide, tongueshaped. Embolus long, thin, proximally covered by conductor. Conductor longer than wide, slightly curved, arising meso-retrolaterally from bulb, extending clockwise, with a membranous end.

Variation
The total length in male specimens examined ranges from 4.79 to 5.29, in female specimens from 4.95 to 6.74.

Discussion
The genus Meta resembles Metellina Chamberlin &Ivie, 1941 andMetleucauge Levi, 1980, but can be distinguished by the following characters. Meta fertilization ducts cross over the spermathecae and the metaine embolic apophysis is fused to the embolus base (Álvarez-Padilla & Hormiga 2011, fi gs 58cf, 60a-c), whereas Metellina fertilization ducts originate on the anterior surface of the spermathecae (Álvarez-Padilla & Hormiga 2011, fi gs 68c, 70d). The Metleucauge epigynum is fl at with two deep atria, the male palpal trochanter has a large distal apophysis, and the male palpal femora and tibia are longer than four times its width (Álvarez-Padilla & Hormiga 2011, fi g. 79a, b). The copulatory openings of Meta open posteriorly, apparently the only metaine that does so (Kallal & Hormiga 2018). The CEP of Meta is wider than in Metellina and has a little spike on the surface. Zhinu has a near-circular gap in the cymbium, the palp is much larger, and the CEP is complex and sclertorized (Kallal & Hormiga 2018). Moreover, the fi ve new species fi t the basic characteristics of Meta.
The members of genus Meta can be found in dark cliffs around cave entrances or among large stones in forest gullies. Due to the specifi c and isolated habitats of Meta species, the existence of species endemic to individual caves is expected. Continued exploration of the Gongligong Mountains will no doubt lead to the discovery of new species of the long-jawed orbweavers.