INTRODUCTION
The dictynid spider genus Lathys comprises 45 species known from Holarctic and Oriental regions (World Spider Catalog 2015). A total four species of the genus have been recorded in Korea: L. dihamataPaik, 1979, L. sexoculataSeo and Sohn, 1984, L. maculosa (Karsch, 1879) and L. stigmatisata (Menge, 1869) (Namkung et al. 2009; Paik 1978 ).
The theridiid spiders genera Robertus and Theridion consist of 45 and 590 species described around the world (World Spider Catalog 2015). One Robertus and seven Theridion species have been recorded in Korea (Namkung et al. 2009): R. naejangensisSeo, 2005, T. longipalpumZhu, 1998, T. longipiliSeo, 2004, T. palgongensePaik, 1996, T. pictum (Walckenaer, 1802), T. pinastriKoch, 1872, T. submirabile Zhu and Song, 1993 and T. taegensePaik, 1996.
While studying specimens collected during the Korean indigenous species survey, the author identified a new species, Robertus subtilis n. sp., and two species new to Korea, Theridion serpatusumGuan and Zhu, 1993 and Lathys annulataBösenberg and Strand, 1906, and reported these species with habitus photos and illustrations in the present paper.
MATERIALS AND METHODS
Specimens were examined and measured using a stereomicroscope (Leica S8APO, Singapore). Photographs were taken with a digital camera (Leica DFC 420) and the images were combined using image stacking software (i-Solution, Future Science Co. Ltd., Taejeon, Korea).
The abbreviations in the text follow Seo (2014a, b): Somatic morphology - c, carapace length; l, length; w, width. Leg I, length of leg I; Fem. I, length of femur I; Pat. I, length of patella; Tib. I, length of tibia I; Met. I, length of metatarsus I; Tar. I, length of tarsus I; Fem I l/d, femur I length divided by femur I diameter. The sequence of leg segments in measurement data is as follows: total (femur, patella, tibia, metatarsus, tarsus). Eye area - AER, anterior eye row; ALE, anterior lateral eye; ALE-PLE, distance between ALE and PLE; AME, anterior median eye; AME-ALE, distance between AME and ALE; AME-AME, distance between AMEs; AME-PME, distance between AME and PME; PER, posterior eye row; PLE, posterior lateral eye; PME, posterior median eye; PME-PLE, distance between PME and PLE; PME-PME, distance between PMEs.
All measurements in the text are given in millimeters. The examined specimens are deposited in the National Institute of Biological Resources (NIBR), Ministry of Environment, Korea.
RESULTS AND DISCUSSION
Order Araneae Clerck, 1757 거미목
Family Dictynidae Pickard-Cambridge, 1871 잎거미과
Genus LathysSimon, 1884 마른잎거미속
Lathys annulataBösenberg and Strand, 1906 한산마른잎거미 (신칭) (Fig. 1)
Synonyms: Lathys annulataBösenberg and Strand, 1906: 110; Ono, 2003: 11; Ono and Ogata, 2009: 134.
Material examined: 1♂, trekking trail (34°47′46″N, 128° 28′40″E, alt. 82 m), 330 m northeast of Jeseungdang on Isl. Hansan, Hansan-myeon, Tongyeong-si, Gyeongsangnam-do, 12 May 2013, B. K. Seo.
Diagnosis: The male of L. annulata is very similar to that of L. maculosa in the abdominal pattern and the terminal part of palp conductor. However, the former can be easily distinguished from the latter by the twice twisted tip of terminal part of conductor and the dorsal tibial apophysis protruded dorsally (Fig. 1D, G).
Description: Male. Total length 2.60. Habitus as in Fig. 1A. Carapace 1.30 long, 0.95 wide, brown with radiated stripes; cervical groove distinct; clypeus height 1.3 times of diameter of AME. AER 0.46, PER 0.51; AER retrocurved slightly and PER straight in dorsal view. AME 0.05, ALE 0.12, PME 0.09, PLE 0.10, AME-AME 0.05, AME-ALE 0.05, PME-PME 0.09, PME-PLE 0.07, AME-PME 0.08, and ALE-PLE contiguous. Median ocular quadrangle, posterior side>height>anterior side (20 : 18 : 13). Chelicera with two promarginal and three retromarginal teeth. Sternum 0.69 long, 0.65 wide. Labium 0.20 long, 0.23 wide. Leg measurements: I 4.34 (1.20, 0.43, 1.10, 1.08, 0.53), II 3.36 (1.00, 0.35, 0.78, 0.80, 0.43), III 2.42 (0.73, 0.28, 0.48, 0.58, 0.35), IV 2.91 (0.85, 0.30, 0.65, 0.73, 0.38). Fem. I l/ w 4.80. Tib. I l/w 7.33. Leg I/c 3.34. Fem. I/c 0.92. Tib I/ c 0.85. Met I/c 0.83. Pat. I+tib. I/c 1.18. Met. I/tar. I 2.04. Met. IV/tar. IV 1.92. Abdomen 1.35 long, 1.10 wide, and oval; dorsum brown with five chevron patterns medially. Palpal organ (Fig. 1B-G); tibia with a retrolateral and a dorsal apophysis that grip the terminal part of conductor; tip of terminal part of conductor twisted twice; fine embolus whirled clockwise.
Habitat: Grassland around trekking trail.
World Distribution: Japan, Korea (Gyeongsangnam-do).
Deposition: NIBRIV0000321391.
Identifer: Bo Keun Seo.
Lathys dihamataPaik, 1979 쌍칼퀴마른잎거미
Synonyms: Lathys dihamataPaik, 1979: 424.
Lathys sexoculataSeo and Sohn, 1984 육눈이마른잎거미
Synonyms: Lathys sexoculataSeo and Sohn, 1984: 114.
Lathys maculosa (Karsch, 1879) 마른잎거미
Synonyms: Dictyna maculosa Karsch, 1879: 96.
Lathys humilis Paik, 1978: 185 (f, misidentified).
Lathys stigmatisata (Menge, 1869) 공산마른잎거미
Synonyms: Lethia stigmatisataMenge, 1869: 250.
Lathys stigmatisataNamkung, 2003: 385.
Family Theridiidae Sundevall,1833 꼬마거미과 Genus RobertusPickard-Cambridge, 1879 민무늬꼬마거미속
Robertus naejangensisSeo, 2005 내장꼬마거미
Synonyms: Robertus naejangensisSeo, 2005: 121.
Robertus subtilis sp. nov. 뾰족수염꼬마거미 (신칭) (Fig. 2)
Material examined: Holotype: ♂, riverside near Dongsan bridge around Weoljeong Temple in Mt. Odae (37°42′29″N, 128°35′49″E, alt. 390 m), Jinbu-myeon, Pyeongchang-gun, Gangweon-do, 9 September 2007, S. Y. Kim. Paratype: 1♀, same data as holotype.
Etymology: The specific name comes from the Latin adjective subtilis meaning “fine” and refers to the shape of the embolus.
Diagnosis: The male of R. subtilis n. sp. is very similar to that of R. ogataiYoshida, 1995 in the fine embolus, the slightly curved conductor enclosing the embolus, and the longish broad tegular apophysis, but can be easily distinguished from the latter by the broad-based conductor in retrolateral view (Fig. 2C-E, I-K). The female of R. subtilis is clearly different from that of R. ogatai in the shape of genital duct and fertilization duct, and the position of the copulatory opening (Fig. 2G-H, M, N).
Description: Male holotype. Total length 3.30. Habitus as in Fig. 1A. Carapace 1.65 long, 1.25 wide, reddish brown with radiated dark stripes; median furrow and cervical groove distinct; cephalon 0.85 wide; clypeus height 2.4 times of diameter of AME. AER 0.47, PER 0.51; AER retrocurved slightly and PER straight in dorsal view. AME 0.09, ALE 0.12, PME 0.07, PLE 0.10, AME-AME 0.04, AME-ALE 0.04, PME-PME 0.22, PME-PLE 0.08, AMEPME 0.05, and ALE-PLE contiguous. Median ocular quadrangle, posterior side>height>anterior side (18 : 16 : 14). Chelicera with three promarginal and two retromarginal teeth. Sternum 0.86 long, 0.81 wide. Labium 0.18 long, 0.29 wide. Leg measurements: I 4.69 (1.33, 0.55, 1.18, 0.93, 0.70), II 3.96 (1.13, 0.50, 0.93, 0.75, 0.65), III 3.37 (0.95, 0.43, 0.68, 0.68, 0.63), IV 4.61 (1.30, 0.48, 1.15, 0.95, 0.73). Fem. I l/w 3.80. Tib. I l/w 5.90. Leg I/c 2.84. Fem. I/c 0.81. Tib I/ c 0.72. Met I/c 0.56. Pat. I+tib. I/c 1.05. Met. I/tar. I 1.33.
Met. IV/tar. IV 1.30. Abdomen 1.80 long, 1.10 wide, oval; dorsum dark gray with two pairs of sigilla. Palpal organ (Fig. 2C-E, I-K); cymbium with a longish sharp paracymbium; terminal parts of embolus and conductor long and fine, but conductor base very broad; tegular apophysis longish broad.
Female (paratype). Total length 2.60. Habitus as in Fig. 2B. Carapace 1.50 long, 1.10 wide; cephalon 0.78 wide; clypeus height 3.8 times of diameter of AME. AER 0.41, PER 0.44; AME 0.05, ALE 0.10, PME 0.07, PLE 0.10, AME-AME 0.07, AME-ALE 0.04, PME-PME 0.07, PMEPLE 0.08, AME-PME 0.04, and ALE-PLE contiguous. Median ocular quadrangle, posterior side>height>anterior side (16 : 13.5 : 13). Chelicera with three promarginal and two retromarginal teeth. Sternum 0.75 long, 0.68 wide. Labium 0.18 long, 0.29 wide. Leg measurements: I 3.82 (1.13, 0.48, 0.90, 0.73, 0.58), II 3.35 (0.98, 0.43, 0.75, 0.61, 0.58), III 2.89 (0.83, 0.38, 0.58, 0.55, 0.55), IV 3.86 (1.13, 0.43, 0.95, 0.75, 0.60). Fem. I l/w 3.77. Tib. I l/w 4.80. Leg I/c 2.55. Fem. I/c 0.75. Tib I/c 0.60. Met I/c 0.49. Pat. I+tib. I/ c 0.92. Met. I/tar. I 1.26. Met. IV/tar. IV 1.25. Abdomen 1.35 long, 1.00 wide. Epigynum (Fig. 2F-H, L-N; genital duct long and coiled; copulatory opening in middle on epigynal plate; fertilization duct very long.
Habitat: Riverside grassland.
World Distribution: Korea (Gyeongsangnam-do).
Deposition: NIBRIV0000321390.
Identifer: Bo Keun Seo.
Genus Theridion Walckenaer, 1805 꼬마거미속
Theridion longipalpum Zhu, 1998 긴수염꼬마거미 Synonyms: Theridion longipalpum Zhu, 1998: 193; Seo, 2005: 125.
Theridion longipiliSeo, 2004 긴털꼬마거미
Synonyms: Theridion longipiliSeo, 2004: 79.
Theridion palgongensePaik, 1996 팔공꼬마거미
Synonyms: Theridion palgongensePaik, 1996: 9.
Theridion pictum (Walckenaer, 1802) 붉은등줄꼬마거미
Synonyms: Aranea picta Walckenaer, 1802: 207 Theridion pictumNamkung, 1976: 84.
Theridion pinastriKoch, 1872 등줄꼬마거미
Synonyms: Theridion pinastri L. Koch, 1872: 249; Paik, 1957: 43.
Theridion serpatusumGuan and Zhu, 1993 주걱꼬마거미 (신칭) (Fig. 3)
Synonyms: Theridion serpatusum Guan and Zhu, in Zhu, Gao and Guan, 1993: 92; Zhu, 1998: 194; Song, Zhu and Chen, 1999: 142.
Material examined: 1♂, Mongolian oak (Quercus mongolica) forest on the other side of Daegwallyeong rest area (37° 41′01″N, 128°45′14″E, alt. 842 m), Doam-myeon, Pyeongchang- gun, Gangwon-do, 10 June 2010, J. C. Lim.
Diagnosis: The male of T. serpatusum is similar to that of Yunohamella yunohamensis (Bösenberg & Strand, 1906) in the abdominal pattern, but can be easily distinguished from the latter and the other congeneric species by the scoopshaped conductor of palpal organ (Fig. 3B-G).
Description: Male. Total length 2.48. Habitus as in Fig. 3A. Carapace 1.18 long, 1.03 wide, with Y-shaped groove making cervical groove and median furrow; clypeus height 3.1 times of diameter of AME. AER 0.47, PER 0.51; AER retrocurved slightly and PER straight in dorsal view. AME 0.09, ALE 0.09, PME 0.08, PLE 0.09, AME-AME 0.10, AME-ALE 0.03, PME-PME 0.07, PME-PLE 0.09, AMEPME 0.10, and ALE-PLE contiguous. Median ocular quadrangle, anterior side>height>posterior side (21 : 20 : 18). Chelicera with three promarginal teeth. Sternum 0.74 long, 0.69 wide. Labium 0.13 long, 0.25 wide. Legs yellow; first and second femora with two broad brown rings distally, other femora with one distal ring; all tibiae and metatarsi with a brown rings at middle and at distal part; all tarsi with a broad brown ring at middle part. Leg measurements: I 7.76 (2.23, 0.55, 1.18, 2.30, 0.80), II 5.44 (1.63, 0.50, 1.25, 1.43, 0.63), III 3.62 (1.13, 0.38, 0.68, 0.93, 0.50), IV 4.71 (1.45, 0.45, 1.03, 1.25, 0.53). Fem. I l/w 9.91. Tib. I l/w 12.53. Leg I/c 6.58. Fem. I/c 1.89. Tib I/c 1.59. Met I/c 1.95. Pat. I+tib. I/c 2.06. Met. I/tar. I 2.88. Met. IV/tar. IV 2.36. Abdomen 1.35 long, 1.13 wide, and oval; dorsum black with a median white pattern; venter pale yellow with light brown area anterior to epigastric furrow and posterior brown area of median part.
Palpal organ (Fig. 3B-G); tapering embolus wrapped by scoop-shaped conductor; tegular and median apophyses small; cymbium with small hood-like paracymbium.
Habitat: Mongolian oak (Quercus mongolica) forest.
World Distribution: China, Korea (Gangwon-do).
Deposition: NIBRIV0000321392.
Identifer: Bo Keun Seo.