A survey of linyphiid spiders from Xishuangbanna, Yunnan Province, China (Araneae, Linyphiidae)

Abstract Eight new genera and 30 new species are described: Cirrosus gen. n. (type species Cirrosus atrocaudatus sp. n. (♂♀)), Conglin gen. n. (type species Conglin personatus sp. n. (♀)), Curtimeticus gen. n. (type species Curtimeticus nebulosus sp. n. (♂)), Gladiata gen. n. (type species Gladiata fengli sp. n. (♂)), Glebala gen. n. (type species Glebala aspera sp. n. (♂)), Glomerosus gen. n. (type species Glomerosus lateralis sp. n. (♂)), Smerasia gen. n. (type species Smerasia obscurus sp. n. (♂♀)), Vittatus gen. n. (type species Vittatus fencha sp. n. (♂♀)); Batueta cuspidata sp. n. (♂♀), Capsulia laciniosa sp. n. (♂), Dactylopisthes separatus sp. n. (♀), Gongylidiellum bracteatum sp. n. (♀), Houshenzinus xiaolongha sp. n. (♂♀), Laogone bai sp. n. (♂), Laogone lunata sp. n. (♂♀), Maro bulbosus sp. n. (♀), Nasoonaria circinata sp. n. (♂♀), Neriene circifolia sp. n. (♂♀), Oedothorax biantu sp. n. (♀), Oilinyphia hengji sp. n. (♂♀), Paikiniana furcata sp. n. (♂♀), Parameioneta bishou sp. n. (♂♀), Parameioneta multifida sp. n. (♂♀), Parameioneta tricolorata sp. n. (♂♀), Tapinopa undata sp. n. (♂), Theoa bidentata sp. n. (♂♀), Theoa vesica sp. n. (♂♀), Vittatus bian sp. n. (♂♀), Vittatus latus sp. n. (♂♀), Vittatus pan sp. n. (♂♀). The male of Kaestneria bicultrata Chen & Yin, 2000 and the females of Asiagone perforata Tanasevitch, 2014 and Batueta similis Wunderlich & Song, 1995 are described for the first time; photos of Bathyphantes paracymbialis Tanasevitch, 2014 are provided.


Introduction
The Linyphiidae is the second most diverse spider family in the world (Platnick 2014). Merrett (1963) studied the detailed structure of male palps of 124 British linyphiids, and grouped them into linyphiines and erigonines; Millidge made a great effort to identify the major lineages of the Linyphiidae based on male palpal morphology (1977), epigynal and tracheal system morphology (1984) respectively, and acknowledged seven subfamilies or groups (1993); Hormiga (2000) integrated a numerical cladistic method in his analysis of erigonine phylogenetic relationships, and found support for the monophyly of the subfamily Erigoninae. As suggested by Tanasevitch (2014a), the Linyphiidae should now be divided into the seven subfamilies: Dubiaraneinae Millidge, 1993, Erigoninae Emerton, 1882, Ipainae Saaristo, 2007, Linyphiinae Blackwall, 1859, Micronetinae Hull, 1920, Mynogleninae Lehtinen, 1967and Stemonyphantinae Wunderlich, 1986 It is commonly acknowledged that the linyphiid spiders are the dominant spider group of the temperate and cold regions of the northern hemisphere (Marusik and Koponen 2002;Paquin and Dupérré 2003;Scharff et al. 2003;Scharff and Gudik-Sørensen 2006). Although the study of its diversity is still immature, the family seems to be much less diverse in the subtropical and tropical regions (Scharff 1990;Sørensen et al. 2002;Floren and Deeleman-Reinhold 2005). Only a few works have focused upon the Linyphiidae in Southeast Asia (Thorell 1898;Locket 1982;Millidge and Russellsmith 1992;Millidge 1995;Tanasevitch 2010;Tanasevitch 2014b). Thorell described eight Erigone species and two Linyphia species from Myanmar (Thorell 1895(Thorell , 1898 but the lack of illustrations in these two works made it difficult to use them for further identifications; Thorell's work was later revised by van Helsdingen (1969) and Tanasevitch (2010) respectively, and useful figures were added; Locket (1982) investigated linyphiid species from western Malaysia, from where fourteen species were reported and five new genera were established; eleven new genera of Linyphiidae from rain forests of Southeast Asia were described by Millidge and Russell-Smith (1992); Tanasevitch (2014b) established two new genera from Laos: Asiagone Tanasevitch, 2014, andLaogone Tanasevitch, 2014, and in addition, he reported 6 new species.
Xishuangbanna of southern Yunnan belongs to the transitional zone from tropical southern Asia to subtropical East Asia . Only a small number of linyphiid spiders have been reported from Xishuangbanna in the past studies, in contrast with the large number of spiders of less diverse groups found there (Tang and Li 2010;Gao and Li 2014). In 1995, one new genus Nasoonaria Wunderlich & Song, 1995 from Xishuangbanna, Yunnan was established and two new species were described: Nasoonaria sinensis Wunderlich & Song, 1995 and Batueta similis Wunderlich & Song, 1995, the latter is the first species of genus Batueta Locket, 1982 to be found outside of western Malaysia (Wunderlich and Song 1995), where this genus was originally described. In 2010, a new species Neriene poculiforma  was reported from Xishuangbanna, Yunnan , which is the twenty-ninth Neriene species found in China, making China the country harboring almost half of the total number of Neriene species.
Our research on the linyphiids in the tropical rain forest in Xishuangbanna of southern Yunnan has revealed 30 new species, together with 18 species already described, making a total of 48 from this tropical area.

Material and methods
Specimens in this study were mainly collected by fogging, trapping, sieving and handcollecting from tree canopy, tree trunks, and leaf-litter in tropical rain forest in Xishuangbanna, Yunnan (the four main collection localities are shown in Fig. 120). Collections were made throughout the year by Qingyuan Zhao, Guo Zheng, Zhiyuan Yao, Zhigang Chen and Guo Tang. Unless otherwise indicated all type specimens are deposited in the Institute of Zoology, Chinese Academy of Sciences in Beijing (IZCAS).
Specimens were examined using a LEICA M205 C stereomicroscope. Further details were studied under a BX51 compound microscope. Most illustrations were made using a camera lucida attached to an Olympus BX51 compound microscope, and then inked on ink jet plotter paper, and the rest were made from photographs. Male and female genitalia were examined and illustrated after being dissected from the spiders.
Left male palps are illustrated, except as otherwise indicated; photos and illustrations of right palps are flipped in figures to allow easy comparison with other species. Epigynes were removed and cleared in lactic acid or warm 10% potassium hydroxide (KOH) solution before illustration. All embolic divisions and vulvae were imaged after being embedded in Arabic gum. Photos were taken with an Olympus c7070 wide zoom digital camera (7.1 megapixels) mounted on an Olympus BX51 compound microscope. Images from multiple focal planes were combined using Helicon Focus (version 3.10) image stacking software. All measurements are given in millimeters. Eye diameters were measured at their widest extent. Leg measurements are shown as: total length (femur, patella, tibia, metatarsus, tarsus). The terminology of Erigoninae genitalic structure follows Hormiga (2000) and Tanasevitch (2014b); the nomenclature of Micronetinae genitalic structure is given after Saaristo and Tanasevitch (1996); the names of Linyphiinae copulatory organs follow van Helsdingen (1969).
Metatarsal trichobothrium (Tm) is given as the ratio of the distance between the proximal margin of the metatarsus and the root of the trichobothrium divided by the total length of the metatarsus (Denis 1949;Locket and Millidge 1953) and Tm value for the first and the fourth leg is given as TmI, TmIV respectively. The tibial spine formula, which expresses the number of dorsal tibial spines on each of legs I to IV, is given for species in which it differs from the type species of the genus. The patellar spine formula is given only if it differs from the most common one (1-1-1-1).
For the known species only the references for their original description and the synonyms of their current valid names are given. All the other synonyms and references are listed in Platnick's world spider catalog (2014).
Several species collected from canopy possessed a similar habitus. To verify the accuracy of pairing, the canopy linyphiids specimens were sequenced for DNA barcodes with the primers: 5'-GGTCAACAAATCATAAAGATATTGG-3' and 5'-TAAACTTCAGGGTGACCAAAAAATCA-3' (Folmer et al. 1994). This sequence data set, together with COI sequences of linyphiid spiders from BOLD (http://www. boldsystems.org) (see more information in Table 1), was analysed using MEGA 5 (Tamura et al. 2011) and a Neighbor-joining tree was constructed.
Abbreviations and conventions. Abbreviations used in the text are given in Table 2. References to figures in cited papers are listed in lowercase type ( fig.); figures of this paper are noted with an initial capital ( Fig.).
When extra materials are examined and recorded, and the paratype's collecting information is the same as holotype's, it will be implied in brackets as [same data as holotype]. anterior lateral eye AME anterior median eye AME-ALE distance between AME and ALE AME-AME distance between AME and AME PLE posterior lateral eye PME posterior median eye PME-PLE distance between PME and PLE PME-PME distance between PME and PME
Diagnosis. This species is similar to C. tianmushana (Chen & Song, 1987) greatly, but differs by the following aspects: the edge of anterior terminal apophysis in C. laciniosa sp. n. is dentate (Fig. 18C), but smooth in C. tianmushana; the apex of pseudolamella in C. tianmushana is broad and strongly papillate (Saaristo et al. 2006: figs 18, 19, 21), while narrower and slightly bifurcate in C. laciniosa sp. n. (Fig. 17A-C); the thumb of embolus in C. laciniosa sp. n. is wider, but less pointed (Fig. 17C).
Female. Unknown. Distribution. Known only from type locality.
Diagnosis. This new genus is distinguished from all other linyphiids by its unique structure of embolic division, notably, by its hooked distal suprategular apophysis running along the tegulum (Fig. 20B), and long, filiform embolus, starting from the prolateral side of the embolic division, forming several coils (Fig. 20A, C-D), which is rarely seen in other genera.
Diagnosis. This new genus is diagnosed by its prominent anterior radical process and the stout, short embolus. Its embolic division is similar to those in members of genus Tmeticus Menge, 1868, Donacochara Simon, 1884. All of them have a simple, straight embolic division with an embolus proper (Millidge 1977: fig. 41), but it differs from the other two by having a bifurcate anterior radical process (Figs 26A, 29A), each branch with a blunt tip ( Fig. 26C-D) and an inconspicuous tailpiece. It is also clearly distinguished by the short palpal tibia with broad distal end and the short palpal patella without ventral teeth ( Fig. 27C-E). The epigyne in female resembles that in Oedothorax Bertkau, 1883 (Roberts 1987: figs 59b-o), but has longer copulatory ducts; The epigyne of female paratype is also quite similar to those in Paratmeticus bipunctis (Bösenberg & Strand, 1906) and Tmeticus nigriceps (Kulczyński, 1916) in ventral view (Marusik and Koponen 2010: figs 14, 18), but differs by the route of copulatory ducts (Figs 28C, 29D).
Remarks. The diagnosis of this species is solely based on the female specimens and the genera within or related to the Savignia group share very similar epigynal structure, which makes it rather difficult to place species in correct genus by comparing epigynes only. The value of TmI of this species and the pattern on its abdomen's dorsum seem to be different from other existing congeners in Dactylopisthes, but it could be tentatively placed in this genus because of its resemblance to D. locketi. A more reasonable diagnosis will be made when the male specimens are collected and studied.
Diagnosis. The number of spines on tibia IV and the conformation of male palp implies that this genus should belong to subfamily Erigoninae, and the conspicuously large proximal cymbial projection resembles that in erigonine genera Minicia Thorell, 1875, Eskovia Marusik & Saaristo, 1999, Sintula Simon, 1884. The embolus in this new genus takes an anti-clockwise route to form a loop, in contrast with the distal suprategular apophysis turning clockwise (Fig. 33B), which is rare in other erigonines. The atrium in female's epigyne resembles that in the genus Ketambea Millidge & Russell-Smith, 1992, Tapinocyba Simon, 1884, but the copulatory ducts follow a different route.
Diagnosis. This genus is unique for its knobble paracymbium (Fig. 36B), which is not known in any other linyphiid genera. The bulb is distinguished by the ambiguous delimitation of the tegulum and subtegulum (Fig. 36A).
Male palp: tibia with two retrolateral trichobothria, with a row of setae dorsally. Cymbium hoof-like ( Fig. 36A-B). Paracymbium with rough surface, strongly reduced ( Fig. 36B). The bulb simple. Distal suprategular apophysis with two branches, one broad at tip, another long and curved, with bifid tip and two small processes at the mid-part ( Fig. 36A-D). Radical apophysis spear-like (Fig. 36B). The embolus long, membraneous, stretching distally, with a slightly-bent, blunt-ended tip ( Fig. 36A Etymology. The specific name is derived from the Latin word 'asper', meaning 'rough', in reference to the rough surface of the paracymbium; adjective.
Diagnosis. See diagnosis of the genus. Abdominal pattern of this species is notably similar to that in Gladiata fengli sp. n.
Genus Glomerosus gen. n. http: Type species. Glomerosus lateralis sp. n. Etymology. The generic name is an arbitrary combination of letters. Gender is masculine.
Diagnosis. The genus is diagnosed by the unique palp: tibia without any apophysis (Figs 39A-B, 40A-B); bulb is globe-like (Fig. 39B); paracymbium slender, 'J'-shaped, the base of which is closely attached to cymbium (Fig. 39B); the embolus is similar to that in genus Plectembolus Millidge & Russell-Smith, 1992 and Plicatiductus Millidge & Russell-Smith 1992 known from Southeast Asia, but Glomerosus gen. n. has fewer coils and a whip-like, loose tip (Fig. 39D). The embolic division has a less sclerotised terminal apophysis, which is small with an attenuated tip (Fig. 39A).

Genus Gongylidiellum Simon, 1884
Gongylidiellum: Etymology. This name comes from the Latin word 'bracteatus', which means 'covered by scale, small plate', in reference to the scale-shaped structure on the ventral plate; adjective.

Genus Houshenzinus Tanasevitch, 2006
Houshenzinus: Tanasevitch  Etymology. This species's name is derived from the Chinese Pinyin 'xiǎo lóng hā', which is the type locality of this species; term in apposition.
Diagnosis. This species is distinguished by the shape of convector in male ( Fig. 45B; Tanasevitch 2006b: figs 45-46) and the loops of copulatory ducts in female's epigyne ( Fig. 46C; Song and Li 2008: fig. 287), but differs from the type species by the inconspicuous dorsal tibial apophysis (Fig. 45A) and ridges on convector in male's palp ( Fig.  44A-B), and three more loops than the copulatory ducts make in female's epigyne.
Distribution. Known only from type locality.

Genus Hylyphantes Simon, 1884
Hylyphantes: Simon 1884: 464. Type species Erigone nigrita Simon, 1881. Diagnosis. The female is easily recognized by the copulatory duct route and the finger-like spines on each side of the ventral plate (Chen and Yin 2000: figs 18-19). The male is similar to K. pullata O. P. -Cambridge, 1863(Roberts 1987) and K. minima Locket, 1982, but differs by the shape of paracymbium and embolic division (Fig. 47B, D). Both male and female differ from other congeners by having pattern on carapace and abdomen.
Remarks. Male of the species is reported for the first time.

Genus Laogone Tanasevitch, 2014
Laogone: Tanasevitch  Etymology. This species's name is derived from the Chinese Pinyin 'bái', meaning 'white', which refers to the color of the holotype's body; term in apposition.
Diagnosis. This species is similar to the type species L. cephala, but differs by the long and pointed dorsal tibial process, and the slimmer membrosclerum.
Diagnosis. This species is similar to the type species L. cephala (Tanasevitch 2014b: figs 28, 30-32;Fig. 52B), but differs by the short dorsal tibial apophysis, and the shape of membrosclerum.
Male. Unknown. Distribution. Known only from type localities.
Diagnosis. Male of N. circinata sp. n. can be distinguished from the type species by the modified carapace (Fig. 59E), prominent distal suprategular apophysis and the long, coiled embolus in palp (Fig. 58B). The female is distinguished from N. sinensis Wunderlich & Song, 1995 by the different pathway taken by the copulatory ducts and by the position of spermathecae (Fig. 60C).
Distribution. Known only from type localities. Etymology. This specific name originates from the Latin words 'circum' meaning 'in a circle' and 'folius' meaning 'leaf ', referring to the shape of the median membrane, the apex of which looks like a small, round leaf; term in apposition.

Nasoonaria sinensis Wunderlich & Song, 1995
Diagnosis. This species is similar to N. birmanica (Thorell, 1887) by having small paracymbium with a curved, filiform tip (Fig. 62B) and the stout, wide terminal apophysis forming about one coil (Fig. 62D). It could be distinguished from N. birmanica by the shape of embolus and lamella. Neriene birmanica has sword-like embolus (Xu et al. 2010: fig. 6), a slim, spear-like lateral projection of the lamella (Xu et al. 2010: fig.  3), while N. circifolia sp. n. has a rostriform embolus, slightly curved at tip (Fig. 62C), and a broader and more sclerotized lateral projection of lamella (Fig. 62A). In female's epigyne, the spiral grooves forming one more coil than that in N. birmanica (Fig. 64C).
Distribution. Known only from type localities. Remarks. We have closely examined and taken photos of the holotype of Ambengana complexipalpis Millidge & Russell-Smith, 1992 (Museum of Natural History, Geneva, Dr Peter J. Schwendinger), both the left palp and the habitus (Fig. 66). By comparing it with the pictures from Xu's paper (Xu et al. 2010: figs 1-7), a few differences were found in the detailed structure of palp between two species. Whether or not the new synonymy proposed by Xu et al. (2010) is valid is uncertain, and a further study is required.
Etymology. This name comes from the Chinese Pinyin 'biān tū', meaning 'knobs on each side', referring to the prominence on each side of the ventral plate of epigyne; noun in apposition.
Male. Unknown. Distribution. Known only from type locality.

Genus Oilinyphia Ono & Saito, 1989
Oilinyphia: Ono and Saito 1989: 232 Etymology. The name comes from the Chinese Pinyin 'héng jĭ', which means 'ridge', referring to the transversal ridges on the dorsum of its abdomen; noun in apposition.
Diagnosis. This species is similar to O. jadbounorum Ponksee & Tanikawa, 2010 from Thailand by the body shape, conformation of palp and epigyne, but differs from sibling species by wide tip of the embolus (Fig. 69A) (pointed in O. jadbounorum (Ponksee and Tanikawa 2010: fig. 3)). Females of two species differ by the shape of the median extension of the ventral plate tapering in O. jadbounorum (Ponksee and Tanikawa 2010: fig. 2) and almost rectangular in the new species (Fig. 71A). The new species clearly differs from the generotype by having TmIV, 2 cheliceral teeth instead of 3, small papillae on the abdomen and by the shape of the copulatory organs.
Distribution. Known only from type localities.

Genus Paikiniana Eskov, 1992
Paikiniana: Etymology. This specific name was taken from the Latin word 'furcatus', which means 'forked', referring to the bifurcate tip of the distal suprategular process; adjective.
Diagnosis. The male is easily distinguished from other Paikiniana species by the forked end of distal suprategular apophysis and the slightly acute angle formed by the two retrolateral tibial apophyses (Fig. 73A-B). The shape of carapace lobe in P. furcillata sp. n. resembles that in P. vulgaris (Oi, 1960) (Oi 1960: fig. 15), but differs from it by the detailed structure of distal suprategular apophysis. The embolic division resembles that in P. lurida (Seo, 1991) (Song and Li 2008: fig. 53), but distinguished from it by the shape of embolic basal lobe and tailpiece (Fig. 73C). The female of the new species has a short projection from the dorsal plate (Fig. 75A), short copulatory ducts and large spermathecae (Fig. 75C), and is similar to P. biceps Li, 2008 (Song andLi 2008: figs 42-45).
Distribution. Known only from type localities.
Diagnosis. Male of new species is similar to P. biobata , but differs in the following aspects: P. biobata has one curved tibial apophysis   fig. 7A), while P. bishou sp. n. has three (Figs 77A-B, 78A-B); paracymbium's apex in P. bishou sp. n. is broad (Fig. 77B), not as slim as in P. biobata (Tu and Li 2006: fig . 7A); lamella characteristica in P. bishou sp. n. has two branches, both of which are long and pointed (Fig. 78B), while in P. biobata one is pointed, the other is broad at tip   fig. 7C). The female is distinguished from other congeners by the conformation of epigyne.
Distribution. Known only from type localities. Etymology. This name originates from the Latin word 'multi-' and '-fidus', and the combination means 'multiply-clefted', referring to the apex of lamella characteristica; adjective.
Diagnosis. The new species differs from other congeners by the shape of lamella characteristica (Fig. 81A-B) and the tip of embolus (Fig. 81C-D).
Diagnosis. This genus resembles Neotropical genera Smermisia Simon, 1894 andMyrmecomelix Millidge, 1993 in the general appearence of the male palp and the conformation of embolic division (Miller 2007). They all have a plate-like radix, and an erect anterior radical process. Smerasia gen. n. differs from similar genera by having short and weakly sclerotized, less pointed, membranous embolus ( Fig. 89C-D) (Miller 2007: figs 63-64, 104), and the paracymbium in Smerasia gen. n. is attenuated at apex and much more curved in general (Fig. 89B). The epigyne in Smerasia gen. n. is wide and with a convex dorsal plate (Fig. 91A), which is quite different from that in Smermisia and Myrmecomelix.
Genus Tapinopa  Etymology. This name is derived from the Latin word 'undatus', which means 'wavy', referring to the shape of the proximal edge of the paracymbium; adjective.
Diagnosis. This species is related to T. vara Locket, 1982 (from Malaysia), but differs in the shape and size of terminal apophysis (Locket 1982: figs 100-102); the pit hook in T. undata sp. n. is longer and has a more pointed tip compared to the related species (Fig. 93C).
Female. Unknown. Distribution. Known only from type localities.

Tapinopa vara Locket, 1982
Tapinopa vara: Etymology. This name is combined by 'bi', and 'dentatus', meaning 'with two teeth', which refers to the two projections on the lateral margin of the prolateral cymbial outgrowth; adjective.
Diagnosis. This species is distinguished as a member of Theoa by the extension at the dorso-mesal side of cymbium, and the sickle-shaped embolus with Fickert's gland about half way along (Locket 1982 : fig. 87). The large spermathecae on each side of the epigyne also resembles those in T. tricaudata (Locket 1982: fig. 89). It differs from the type species in the following aspects: the apex of cymbial outgrowth in T. bidentata sp. n. is bifid (Fig. 96A), not trifid as in T. tricaudata (Locket 1982: fig. 86); the pit hook in T. bidentata is not a discrete structure and is pointed, which differs from the bifid one in T. tricaudata; the terminal apophyses in the two species are of different shapes (Locket 1982: fig. 84; Fig. 96B); the spermathecae are more distantly spaced in T. bidentata (Fig. 98A). The two species also differ in spination: 1-0-0-0 or 1-1-1-0 in the generotype and 2-2-2-2 in the new taxon.
Distribution. Known only from type localities. Etymology. The name is derived from the Latin word 'vesica', which means 'bladder, purse', referring to the pouch-shaped structure in the vulva; noun in apposition.
Diagnosis. The male is recognized by the huge cymbial outgrowth (Fig. 100B), and the cresent-shaped embolus with large Fickert's gland about half way along (Fig.  100C). The female has unusually small spermathecae situated laterally (Fig. 102C). It also differs from other congeners by having TmIV.
Distribution. Known only from type localities.
Distribution. Known only from type localities. Etymology. The name for this species is derived from the Chinese Pinyin 'fēn chà', which means 'forked', in reference to the fork-shaped anterior radical apophysis in male; term in apposition.
Diagnosis. It differs from other congeners by the stem-cup-shaped dorsal tibial apophysis (Fig. 108B) and the ribbon-like embolus with a small outgrowth near tip in palp (Fig. 109B); female resembles V. bian sp. n. in the closely positioned spermathecae (Figs 106C, 110C), but differs in the short and unmodified scapoid (Fig. 110A).
Distribution. Known only from type localities. Etymology. This name is derived from the Chinese Pinyin 'pán' meaning 'plate', for the broad, plate-like terminal apophysis in this species; noun in apposition.
Diagnosis. It differs from the congener V. bian sp. n. by light coloration, much shorter dorsal tibial apophysis (Fig. 117A), prominent and broad branch of radical apophysis (Fig. 117B) and short scape (as long as wide).
Distribution. Known only from type localities.

Discussion
The process of matching the sexes of the Xishuangbanna linyphiids collected from the forest canopy is arduous, especially with the occurrence of similar habitus and conformation of epigynes (Figs 46,62,99). In order to solve this problem, we conducted molecular work to obtain DNA sequence barcodes of COI from freshly collected linyphiid spiders (mostly from canopies), and constructed a Neighbor-joining tree. The pairing results are shown in Figure 121.
We have described some new species based on only one sex, which is an unconventional act. However, we feel reasonably certain that our conclusions are generally valid and taxonomically informative. While there may be errors in the identification of some species, finding the other sex of monotypic species will take much time and effort, and we believe it is best to share our information as soon as possible. Further investigations should be conducted in Xishuangbanna and neighboring places. More new discoveries will definitely benefit our understanding of the systematics of the linyphiids from Southeast Asia.