A peer-reviewed open-access journal Zookeys 855: 15—30 (2019) earn ee #ZooKeys http:/ /Z00 keys -pen soft.net Launched to accelerate biodiversity research On the genus Flexicrurum Tong & Li, 2007 (Araneae, Psilodercidae) from Hainan Island, China Wan-Jin Chang', Fengyuan Li', Shuqiang Li! I Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China Corresponding author: Shugiang Li (lisq@ioz.ac.cn) Academic editor: Abel Pérez-Gonzdlez | Received 8 March 2019 | Accepted 10 May 2019 | Published 13 June 2019 Attp.//zoobank.org/C49C305 1-28 BD-46A8-A5AB-E33C3A0DD9IDD Citation: Chang W-J, Li F Li S (2019) On the genus Flexicrurum Tong & Li, 2007 (Araneae, Psilodercidae) from Hainan Island, China. ZooKeys 855: 15-30. https://doi.org/10.3897/zookeys.855.34383 Abstract ‘Three new species of the genus Flexicrurum Tong & Li, 2007, from Hainan Island, China are described: F wuzhishanense sp. nov. (39), E yangjiao sp. nov. (3°), and EF gishi sp. nov. (3-9). A key to males of spe- cies of Flexicrurum is provided. Additionally, the female of F minutum Tong & Li, 2007, is described for the first time. To date, the genus is endemic to Hainan Island, China. Types are deposited in the Institute of Zoology, Chinese Academy of Sciences (IZCAS) in Beijing. Keywords Endemic, Ochyroceratidae, Southeast Asia, spider, taxonomy, tropical Introduction The spider family Psilodercidae Machado, 1951, was only recently elevated to family rank from a subfamily of Ochyroceratidae Fage, 1912. This taxonomic rearrangement is based on the presence of book-lungs, the position of tracheal stigma, the number of promarginal cheliceral teeth, the shape of the labium, and the point of attachment of the bulbus (Wunderlich 2004, 2008). Psilodercidae currently contains 11 genera and 120 species (World Spider Catalog 2019; Li and Quan 2017). Psilodercids are restricted to tropical Asia and are diverse within China. Thirteen species from six genera have been reported in China: Althepus chengmenensis Li & Li, 2018, A. christae Wang & Li, 2013, A. menglaensis Li & Li, 2018, A. gingyuani Li & Li, 2018, A. xuae Li & Li, 2018, Leclercera undulata Copyright Wan-Jin Chang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. 16 Wan-Jin Chang et al. / ZooKeys 855: 15-30 (2019) Wang & Li, 2013, and Psiloderces incomptus Wang & Li, 2013, from Yunnan Province; Flexicrurum flexicrurum Tong & Li, 2007, F longispina Tong & Li, 2007, F minutum Tong & Li, 2007, and Qiongocera hongjunensis Li & Li, 2017, from Hainan Island; and Sinoderces exilis Wang & Li, 2013, and S. nawanensis Li & Li, 2017, from Guangxi Zhuang Autonomous Region. All of them are locally endemic. Prior to this study, only three species from the genus Flexicrurum Tong & Li, 2007, have been described (Tong and Li 2007): F flexicrurum, E longispina, and F. minutum. These species are confined to Hainan Island, China, and have been the only representa- tives of the genus (World Spider Catalog 2019). While studying new material collected in Hainan Island, we recognized the matched pairs of three new species of Flexicrurum, and a hitherto unknown female of EF minutum, one of the three species described by Tong and Li (2007). This paper describes all of these new discoveries by providing images of their genital organs and close-up photos of their chelicerae. Materials and methods Types are deposited in the Institute of Zoology, Chinese Academy of Sciences (IZCAS) in Beijing. All specimens collected were observed and preserved in 95% ethanol. ‘The speci- mens were measured and examined under a Leica M205 C stereomicroscope, and further morphological details were observed with an Olympus BX41 compound microscope. ‘The left male palp was detached for closer examination. Carapace measurements include the clypeus. The internal genitalia and male bulb were dissected and immersed in lactic acid. An Olympus C7070 wide zoom digital camera (7.1 megapixels) mounted on an Olympus SZX12 stereomicroscope was used to take photos. Photos were stacked with Helicon Focus 6.7.1 to generate images with extended depth of field. The images were post-processed with Adobe Photoshop. Leg measurements are shown as total length (femur, patella, tibia, meta- tarsus, and tarsus). Leg segments were measured from the retrolateral side. All measurements are given in millimetres (mm). Terminology follows that of Li et al. (2014), Tong and Li (2007) and Deeleman-Reinhold (1995). Coordinates of collecting locations were recorded in Microsoft Excel and imported into ArcGIS 10.2 to generate a map which was subse- quently exported to Adobe Photoshop CC 2014 for further editing. The following abbre- viations are used in text: ALE anterior lateral eye, ME median eye, PLE posterior lateral eye. Taxonomy Family Psilodercidae Machado, 1951 Genus Flexicrurum Tong & Li, 2007 Type species. Flexicrurum flexicrurum Tong & Li, 2007 from China, Hainan Island, Wuzhishan, Wuzhishan City, 16.1V.2005 (IZCAS). On the genus Flexicrurum Tong & Li, 2007 from Hainan Island, China 7 Emended diagnosis. Flexicrurum Tong & Li, 2007, resembles Althepus Thorell, 1898, and Leclercera Deeleman-Reinhold, 1995. However, Flexicrurum can be differentiated by the combination of the following characteristics: 1) the tibia of the male palp is strongly rotated inward (vs absence of rotated male palpal tibia in Althepus and Leclercera); 2) presence of a slender bulbal apophysis (vs absence of slender bulbal apophysis in Althepus and. Leclercera); 3) cymbium with a strong lateral protrusion (vs cymbium with slightly tilted protrusion in Althepus and Leclercera); 4) cymbium bearing a one- or two-bulge posterolateral cymbial apophysis (vs cymbium with lateral lanceolate or hook-shaped, spine like apophysis in A/thepus; cymbium with retrolateral apophysis in Leclercera); 5) absence of promarginal cheliceral teeth (vs 1-2 promarginal cheliceral teeth in Althepus and Leclercera); 6) embolus distinctly short (vs embolus long and slender in A/thepus and Leclercera); 7) internal endogyne with the presence of a distinct vertical duct medially bearing different structures of spermathecae (vs absence of the vertical duct in Althepus and Leclercera). Composition. Flexicrurum flexicrurum Tong & Li, 2007, F longispina Tong & Li, 2007, E minutum Tong & Li, 2007, F gishi Li & Li, sp. nov., F wuzhishanense Li & Li, sp. nov., and F yangjiao Li & Li, sp. nov. Distribution. Hainan Island, China. Key to species of Flexicrurum (males only) 1 Cymbium with posterolateral apophysis with a divided tip, i.e., with two bulges or | OXCCONEU OL FAL cl ce ree af RUPE 5 IE Ah A CPV ergs fe Oey ree AR 2 — Cymbium with posterolateral apophysis with a single tip or bulge... 3 2 Conductor simple, protruded; longer bulbal apophysis; bulb with scattered black SO Sacer cde seat rae 0 Aes. Poke rau dasredea ge eased, Mat etcees EF. wuzhishanense sp. nov. — Conductor comprising two parts that spiral inwards, resembling a broken ring; shorter bulbal apophysis; bulb without scattered black spots........ E. qishi sp. nov. 3. Laminar apophysis and tip of cymbial protrusion parallel to one another............ “. — Laminar apophysis and tip of cymbial protrusion not parallel to one another ...... sss tnnslaertonddinehins sven eecenanads gesbanbuaee ste entesnvngeh tea ternesaneaetpeeenesnaes’ EF. yangjiao sp. nov. 4 Absence of long spine on dorsolateral surface of bulb... eee eeeeeseereeeeeeees 5 — Presence of a long spine on dorsolateral surface of bulb... EF longispina 5 Longer bulbal apophysis (exceeds length of entire bulb).......0000.. E. flexicrurum — Shorter bulbal apophysis (does not exceed length of entire bulb)........ E minutum Flexicrurum wuzhishanense Li & Li, sp. nov. http://zoobank.org/7295226A-D99A-458F-BAEB-1E536F77452D Figs 1-2, 8A, 9 Types. Holotype: ¢ (IZCAS), China, Hainan Island, Wuzhishan City, Shuiman Vil- lage, Wuzhishan, 18°54.1944'N, 109°40.9266'E, 723 m, 31.III.2012, Chen Z. leg.; Paratype: 19 (IZCAS), same data as holotype. 18 Wan-Jin Chang et al. / ZooKeys 855: 15-30 (2019) Etymology. The species name is an adjective referring to the type locality; the Chinese pinyin “wt zhi” means five fingers, and “shan” means mountain. The name is a graphic in- terpretation of contour of the mountain ranges with a striking resemblance to five fingers. Diagnosis. Flexicrurum wuzhishanense sp. nov. strongly resembles F gishi sp. nov. Males of F wuzhishanense sp. nov. can be distinguished by a longer bulbal apophysis (Fig. 2D) (vs shorter bulbal apophysis in F gishi sp. nov.), the bulbal apophysis which is further from embolus (Fig. 2B) (vs bulbal apophysis and embolus nearer each other (Fig. 6B), simple protruded conductor comprises only a single part (Fig. 2B) (vs a rath- er slender conductor comprising two parts, resembling a broken ring in F qishi sp. nov. (Fig. GA, B)), the bulb with scattered black spots (Fig. 2A) (vs absence of scattered black spots on bulb of F gishi sp. nov. (Fig. 6A)); females can be distinguished by a rather broad dome-shaped epigastric area (Fig. 1B) (vs a rather plump, triangular epigastric area in F gishi sp. nov. (Fig. 5B)), spermathecae can be distinguished by a pair of lobed ducts laterally connected with bow-tie-shaped spermathecae (Fig. 1A) (vs a pair of sper- mathecae resembling the structure of a human uterus in F gishi sp. nov. (Fig. 5A)). Description. Male (Holotype). Total length 2.46; carapace 0.96 long, 0.94 wide; abdomen 1.50 long, 0.64 wide. Carapace round and brown, with three longitudinal dark brown bands, the middle band is 2 times wider than the lateral bands (Fig. 1C). Fovea shallow and dark brown. Anterior part of thoracic region distinctly elevated. Eye sizes and interdistances: ALE 0.09, ME 0.08, PLE 0.06; ALE—ALE 0.30, ME—ME 0.16, PLE- PLE 0.32, ALE—-ME 0.14, PLE—-ME 0.18, ALE—PLE 0.12. Chelicerae brown. Cheliceral promargin with lamina of three triangular extensions and no teeth, retromargin with two small teeth (Fig. 8A). Clypeus slanting 0.3 high, with dark brown trident and two pale areas laterally. Endites dark brown. Labium slanting and dark brown. Sternum circular with brown complex pattern delimiting a medial small pale spot anteriorly. Abdomen elongated, anterior of ventrum with pair of circular pale areas and dome-shaped epi- gastric area, posterior with random irregular dark brown spots. Legs uniformly brown; measurements: missing (detached from specimens, sequence of legs cannot be differenti- ated). Palp (Fig. 2A—D): femur slender swollen at the base, patella swollen and angled ventrally (Figs 1C, 2C), tibia more slender than femur, distally darker, cymbium pale, darker distally, with strong lateral protrusion darker distally, bearing posterolateral cym- bial apophysis with two bulges (Fig. 2D); bulb brown and pyriform, with scattered dark spots, bearing a pointed laminar apophysis, a protruded conductor and embolus distally; embolus slender, hook-shaped, adjacent to laminar apophysis and conductor (Fig. 2B). Female (Paratype). General features and coloration similar to male (Fig. 1D—E). Measurements: total length 2.12; carapace 0.75 long, 0.78 wide; abdomen 1.37 long, 0.93 wide. Eye sizes and interdistances: ALE 0.09, ME 0.06, PLE 0.08; ALE-ALE 0.30, ME—ME 0.14, PLE-PLE 0.32, ALE—ME 0.14, PLE-ME 0.18, ALE-PLE 0.15. Clypeus 0.35 high. Leg measurements: I missing, II missing, III missing, IV 7.38 (1.92, 0.31, 2.03, 2.03, 1.09). Internal genitalia: a pair of lobe-shaped ducts connected with a bow-tie-shaped spermathecae, divided by a distinct pair of vertical ducts with a pair of club-shaped ducts anteriorly (Fig. 1A). Distribution. Known only from the type locality (Fig. 9). On the genus Flexicrurum Tong & Li, 2007 from Hainan Island, China 19 Figure |. Flexicrurum wuzhishanense Li & Li, sp. nov., male holotype and female paratype A internal genitalia, dorsal view B female epigastric area, ventral view C male habitus, dorsal view D female habitus, dorsal view E female habitus, ventral view. Abbreviation: SP = spermathecae. D and E share the scale bar. 20 Wan-Jin Chang et al. / ZooKeys 855: 15-30 (2019) Figure 2. Flexicrurum wuzhishanense Li & Li, sp. nov., male holotype A palp, ventral view B palpal bulb, ventral view C palp, prolateral view D palp, retrolateral view. Abbreviations: BA = bulbal apophysis, CA = cymbial apophysis, CO = conductor, CP = cymbial protrusion, EM = embolus, LA = laminal apophysis. A and B share the scale bar as well as C and D. On the genus Flexicrurum Tong & Li, 2007 from Hainan Island, China 21 Flexicrurum yangjiao Li & Li, sp. nov. http://zoobank.org/1FDF0627-CE14-4FCB-BA69-2B88FC6EB417 Figs 3-4, 8B, 9 Types. Holotype: 3 (IZCAS), China, Hainan Island, Changjiang City, Bawangling, Yajia Conference Centre, 19°5.1042'N, 109°7.4343’'E, 433 m, 10.[V.2012, Chen Z. leg.; Paratypes: 1112 (IZCAS), same data as holotype. Etymology. The species name is a noun in apposition derived from the word for “goat horn” in Chinese pinyin “yangjido’. It refers to the shape of the conductor which curves strongly inwards, like a goat horn. Diagnosis. Flexicrurum yangjiao sp. nov. can be distinguished from F wuzhishan- ense sp. nov. and EF qishi sp. nov. by a posterolateral cymbial apophysis with a single tip or bulge (Fig. 4D) (vs a posterolateral cymbial apophysis with two bulges or protuber- ances (i.e., a divided tip) in F wuzhishanense sp. nov. and F qishi sp. nov.), a pointed embolic end (vs hook-liked embolic end in F wughishanense sp. nov. and F gishi sp. noy.), a shorter laminar apophysis (vs longer in F wuzhishanense sp. nov. and F. gishi sp. nov.), and the position of the entire bulb is opposite that of the other two species—the laminar apophysis is parallel to the tip of cymbial protrusion (vs laminar apophysis and tip of cymbial protrusion not parallel in F wuzhishanense sp. nov. and F. qgishi sp. nov.). Description. Male (Holotype). Total length 2.08; carapace 0.80 long, 0.96 wide; abdomen 1.28 long, 0.64 wide. Carapace round and brown, with three longitudinal dark brown bands, the middle band 2 times wider than the lateral bands (Fig. 3C). Fovea shallow and dark brown. Anterior part of thoracic region distinctly elevated. Eye sizes and interdistances: ALE 0.08, ME 0.08, PLE 0.09; ALE-ALE 0.30, ME- ME 0.13, PLE-PLE 0.32, ALE-ME 0.16, PLE-ME 0.19, ALE-PLE 0.16. Chelicerae brown. Cheliceral promargin with lamina of three triangular extensions and no teeth, retromargin with two small teeth (Fig. 8B). Clypeus slanting 0.20 high, medially dark brown and two pale areas laterally. Endites dark brown. Labium slanting and dark brown. Sternum circular with brown complex pattern delimiting a 1/3 medial pale spot anteriorly. Abdomen elongated, dorsum anterior 2/3 with random dark brown spots, posterior 1/3 with horizontal dark brown striated pattern medially, ventrum anterior half with pair of lobed pale areas and a dome-shaped epigastric area, posterior half with random, irregular dark brown spots. Legs uniformly brown; measurements: [97502(2:56,50.32),2'88.. 2:65,.1609); Ul 6:64:(2.00,70:25521. 7531.7 15-0:93), Il 5:05 (1.20, 0.23, 1.37, 1.50, 0.75), IV missing. Palp (Fig. 4A—D): femur slender, swollen at the base, patella swollen and angled ventrally (Figs 3C, 4C), tibia swollen and dark distally, cymbium pale, darker distally, with strong lateral protrusion darker distally, bearing a posterolateral cymbial apophysis with a single bulge (Fig. 4D); bulb pale brown and pyriform, bearing a pointed laminar apophysis, a slender bulbal apophysis; conductor strongly spiralled forming a ring resembling a goat horn; embolus short and pointed, located below all other structures, further away from conductor (Fig. 4B). Female (Paratype). General features and coloration similar to male (Fig. 3D-E). Measurements: total length 2.18; carapace 0.80 long, 0.80 wide; abdomen 1.38 long, 0.80 wide. Eye sizes and interdistances: ALE 0.08, ME 0.08, PLE 0.05; ALE-ALE 0.32, 22 Wan-Jin Chang et al. / ZooKeys 855: 15-30 (2019) Figure 3. Flexicrurum yangjiao Li & Li, sp. nov., male holotype and female paratype A internal genitalia, dorsal view B female epigastric area, ventral view C male habitus, dorsal view D female habitus, dorsal view E female habitus, ventral view. Abbreviation: SP = spermathecae. D and E share the scale bar. On the genus Flexicrurum Tong & Li, 2007 from Hainan Island, China 23 Figure 4. Flexicrurum yangiao Li & Li, sp. nov., male holotype A palp, ventral view B palpal bulb, ventral view C palp, prolateral view D palp, retrolateral view. Abbreviations: BA = bulbal apophysis, CA = cymbial apophysis, CO = conductor, CP = cymbial protrusion, EM = embolus, LA = laminal apophysis. A and B share the scale bar as well as C and D. 24 Wan-Jin Chang et al. / ZooKeys 855: 15-30 (2019) ME-ME 0.16, PLE-PLE 0.33, ALE—ME 0.13, PLE-ME 0.19, ALE—PLE 0.13. Clypeus 0.35 high. Leg measurements: I 7.34 (2.00, 0.25, 2.25, 1.75, 1.09), II missing, III 5.10 (1.28, 0.25, 1.75, 1.20, 0.62), IV 6.82 (1.71, 0.31, 2.00, 2.00, 0.80). Internal genitalia: a pair of ovoid ring-shaped spermathecae connected to bow-tie-shaped ducts divided by a pair of distinct vertical ducts, bearing a pair of droplet-shaped ducts laterally (Fig. 3A). Distribution. Known only from the type locality (Fig. 9). Flexicrurum qishi Li & Li, sp. nov. http://zoobank.org/15FA5BD3-172D-4A38-8456-B21BB623D53F Figs 5—6, 8C, 9 Types. Holotype: 3 (IZCAS), China, Hainan Island, Tunchang County, Datong Vil- lage, Mountain Wolong, 19°27.5450'N, 110°7.3150'E, 248 m, 06.VH.2014, Li F and Wang X. leg.; Paratype: 12 (IZCAS), same data as holotype. Etymology. The species name is a noun in apposition derived from the Chinese pinyin “gishi” (knight) and refers to the ventral view of the bulb which resembles a piece in international chess game representing a knight (Fig. GA). Diagnosis. The species is similar to Flexicrurum wuzhishanense sp. nov. Diagnostic features are discussed under E wuzhishanense sp. nov. Description. Male (Holotype). Total length 2.45; carapace 1.25 long, 0.75 wide; abdomen 1.20 long, 0.68 wide. Carapace round and brown, with three longitudinal dark brown bands, the middle band is 2 times wider than the lateral bands (Fig. 5C). Fovea shallow and dark brown. Anterior part of thoracic region distinctly elevated. Eye sizes and interdistances: ALE 0.08, ME 0.06, PLE 0.05; ALE-ALE 0.28, ME-— ME 0.15, PLE-PLE 0.30, ALE—ME 0.16, PLE—-ME 0.18, ALE-PLE 0.13. Chelicerae brown. Cheliceral promargin with lamina of three triangular extensions and no teeth, retromargin with two small teeth (Fig. 8C). Clypeus slanting 0.20 high, medially dark brown and two pale areas laterally. Endites dark brown. Labium slanting and dark brown. Sternum circular with brown complex pattern delimiting a 1/3 medial small pale spot anteriorly and bottom margin. Abdomen elongated, dorsum anterior 2/3 with random dark brown spots, posterior 1/3 with horizontal dark brown striated pat- tern medially, ventrum anterior half with pair of circular pale areas and ovoid epigastric area, posterior half with random irregular dark brown spots. Legs uniformly brown; measurements: missing (detached from specimens, sequence of legs cannot be differen- tiated). Palp (Fig. 6A—D): femur slender, swollen at the base, patella swollen and angled ventrally (Figs 5C, 6C), tibia swollen and darker distally, cymbium pale, darker distally, with strong lateral protrusion darker distally, bearing posterolateral cymbial apophysis with two bulges (Fig. 6D); bulb pale brown and pyriform, bearing a pointed laminar apophysis, a slender bulbal apophysis adjacent to embolus which is located further away from conductor; conductor comprising two parts (two slender conductors circling in- wards) resembling a broken ring; embolus hook-shaped, curving distally (Fig. 6B). Female (Paratype). General features and coloration similar to male (Fig. 5D-E). Measurements: total length 2.15; carapace 0.75 long, 0.78 wide; abdomen 1.40 long, On the genus Flexicrurum Tong & Li, 2007 from Hainan Island, China oe 4 A re Saw oni Siioa | 0.5 mm Figure 5. Flexicrurum qishi Li & Li, sp. nov., male holotype and female paratype A internal genitalia, dorsal view B female epigastric area, ventral view C male habitus, dorsal view D female habitus, dorsal view E female habitus, ventral view. Abbreviation: SP = spermathecae. D and E share the scale bar. Wan-Jin Chang et al. / ZooKeys 855: 15-30 (2019) 26 £ = N So D C Figure 6. Flexicrurum qishi Li & Li, sp. nov., male holotype A palp, ventral view B palpal bulb, ven- tral view C palp, prolateral view D palp, retrolateral view. Abbreviations: BA = bulbal apophysis, CA = cymbial apophysis, CO = conductor, CP = cymbial protrusion, EM = embolus, LA = laminal apophysis. A and B share the scale bar as well as C and D. On the genus Flexicrurum Tong & Li, 2007 from Hainan Island, China LF 0.93 wide. Eye sizes and interdistances: ALE 0.09, ME 0.06, PLE 0.05; ALE—ALE 0.29, ME-ME 0.13, PLE-PLE 0.31, ALE-ME 0.16, PLE-ME 0.18, ALE-PLE 0.14. Cl- ypeus 0.23 high. Leg measurements: I missing, II missing, III missing, IV 6.65 (1.80, 0.25, 1.80, 1.87, 0.93). Internal genitalia: a pair of spermathecae resembling the struc- ture of human uterus (distinct pair of lobe-shaped ducts hanging directed posteriorly, medially with a pair of vertical ducts bearing a curvy, flat duct posteriorly) (Fig. 5A). Distribution. Known only from the type locality (Fig. 9). Flexicrurum minutum Tong & Li, 2007 Figs 7, 9 Flexicrurum minutum Tong and Li, 2007: 65, figs 1I-L, 4A—-E; Tong, 2013: 20, figs 16I-L, 35A-E Type examined. Holotype: 3 (IZCAS), China, Hainan Island, Changjiang County, Bawangling National Natural Reserve, 22.III.2005. Other material. 9 (IZCAS), China, Hainan Island, Dongfang City, Donghe Town, Nanlang Village, foot of Mountain E-Xian, 19°0.3800'N, 109°5.0300'E, 214 m, 16.XI1I.2014, Zhao Q. and Shao L. leg. Description. Female. Total length 2.34; carapace 0.78 long, 0.75 wide; abdo- men 1.56 long, 0.87 wide. Carapace round and brown, with three longitudinal dark brown bands, the middle band is 2 times wider than the lateral bands (Fig. 7C). Fovea shallow and dark brown. Anterior part of thoracic region distinctly elevated. Eye sizes and interdistances: ALE 0.08, ME 0.06, PLE 0.05; ALE-ALE 0.31, ME- ME 0.15, PLE-PLE 0.33, ALE-ME 0.14, PLE-ME 0.18, ALE-PLE 0.15. Cheli- cerae brown. Cheliceral promargin with lamina of three triangular extensions and no teeth, retromargin with two small teeth (Tong and Li 2007). Clypeus slanting 0.24 high, dark brown. Endites dark brown. Labium slanting and dark brown. Sternum circular with brown complex pattern delimiting a medial ovoid pale spot anteriorly. Abdomen elongated, dorsum anterior 2/3 with dark brown striated spacing delimit- ing a pale area medially, posterior 1/3 with horizontal dark brown striated pattern medially, ventrum with brown pattern at margin and anterior half medially pale with an ovoid epigastric area, posterior half with random irregular dark brown pattern (Fig. 7D). Legs uniformly brown; measurements: I 7.85 (2.24, 0.25, 2.40, 1.87, 1:09), TL'5:76:(1560;-0.25, 1,60; 17365.0,75), IID 5,02) (1,755 0203 1520) 253.0762), IV 7.11 (1.87, 0.25, 2.12, 2.00, 0.87). Internal genitalia: a pair of umbrella-shaped spermathecae (a pair of vertical ducts posteriorly connected with pair of ovoid vesicle and covered by a dome anteriorly) (Fig. 7A). Distribution. Hainan Island, China (Fig. 9). Remarks. ‘The female was matched with the holotype male on the basis of proxim- ity of its collection location to the type locality (only about 30 km away), similarities in somatic morphology with the holotype male, and from DNA barcoding data. Wan-Jin Chang et al. / ZooKeys 855: 15-30 (2019) 0.5mm Figure 7. Flexicrurum minutum Tong & Li, 2007, female A internal genitalia, dorsal view B female epigastric area, ventral view C female habitus, dorsal view D female habitus, ventral view. Abbreviation: SP = spermathecae. C and D share the scale bar. On the genus Flexicrurum Tong & Li, 2007 from Hainan Island, China 29 Figure 8. Cheliceral retromargin A Flexicrurum wuzhishanense Li & Li, sp. nov. B FE yangjiao Li & Li, sp. nov. C F qishi Li & Li, sp. nov. Abbreviations: CL = cheliceral laminal, RT = retromargin teeth. A, B and C share the scale bar. 3 HAINAN ISLAND 6 Figure 9. Distribution of Flexicrurum species in Hainan Island, China. 1. F wuzhishanense Li & Li, sp. nov., 2. F yangjiao Li & Li, sp. nov., 3. F gishi Li & Li, sp. nov., 4. E minutum Tong & Li, 2007, 5. F flexicrurum Tong & Li, 2007, 6. F longispina Tong & Li, 2007. 30 Wan-Jin Chang et al. / ZooKeys 855: 15-30 (2019) Acknowledgements The manuscript benefitted greatly from comments by Drs Abel Pérez-Gonzalez and Jie Liu. Sarah Crews and Joseph K. H. Koh kindly improved the English of the text. This study was supported by the National Natural Sciences Foundation of China (NSFC-31530067). References Deeleman-Reinhold CL (1995) The Ochyroceratidae of the Indo-Pacific region (Araneae). The Raffles Bulletin of Zoology, Supplement 2: 1-103. Li F, Li S, Jager P (2014) Six new species of the spider family Ochyroceratidae Fage, 1912 (Arachnida: Araneae) from Southeast Asia. Zootaxa 3768(2): 119-138. https://doi. org/10.11646/zootaxa.3768.2.2 Li S, Quan R (2017) Taxonomy is the cornerstone of biodiversity conservation — SEABRI re- ports on biological surveys in Southeast Asia. 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