Four new epigean spiders of the genus Cybaeus (Araneae: Cybaeidae) from South Korea Author Lee, Sue Yeon 0000-0002-2066-3747 College of Agricultural Life Science, Jeonbuk National University, Jeonju-si 54896, Republic of Korea & hongdan 200 @ naver. com; https: // orcid. org / 0000 - 0002 - 2066 - 3747 hongdan200@naver.com Author Yoo, Jung Sun 0000-0002-3243-2006 Biological and Genetic Resources Utilization Division, National Institute of Biological Resources, Incheon 22689, Republic of Korea Life and Environment Research Institute, Konkuk University, Seoul 05029, Republic of Korea & lycosidae @ korea. kr; https: // orcid. org / 0000 - 0002 - 3243 - 2006 lycosidae@korea.kr Author Kim, Seung Tae text Zootaxa 2021 2021-05-05 4966 4 458 468 journal article 6500 10.11646/zootaxa.4966.4.4 27992481-4564-418c-851f-64ba0c63abfc 1175-5326 4738778 62FE9E52-E3F2-4484-800D-61D916872A5A Cybaeus pseudoauriculatus sp. nov. Figs 4 , 5 Type material. Holotype : male, 27 June 2019 , Mt. Naejangsan , Naejang-dong , Jeongeup-si , Jeollabuk-do , Korea ( 35°29'19" N , 126°54'08" E , alt. 235 m ), leg. S. T . Kim ( NIBR-KDELIV0000003119 ) , Paratypes : 4 males , same data as holotype, leg. S. T . Kim ( NIBR-KDELIV0000006782–85 ) ; 2 males , 17 October 2019 , Mt. Deogyusan , Samgong-ri , Seolcheon-myeon , Muju-gun , Jeollabuk-do , Korea ( 35°53'19.4" N , 127°46'62.3" E , alt. 261 m ), leg. S. T . Kim (KKU-LEI-Ara20190627- CY001–2 ) . Etymology. The specific name is a compound word from the Greek prefix ‘ pseudo ’ meaning similar and the specific name of Cybaeus auriculatus Seo, 2017 . It refers to the similarity in the male palpal organ morphology between both species. Diagnosis. The new species is most similar to Cybaeus auriculatus Seo, 2017 in the shape of the palpal organ, body appearance, and the number of peg setae on the PA, but can be distinguished by the shape of cymbium, embolus and conductor, the number of retromarginal teeth and the presence or absence of the cuticular spine on the retrolateral surface of tibia: males of Cybaeus pseudoauriculatus have a long cymbium ( Figs. 4D–G ), 9 retromarginal teeth ( Fig. 4B ), a windingly curved embolus not wrapped by the conductor ( Fig. 4E–F ), a narrow conductor base and lacks a cuticular spine on the retrolateral surface of the palpal tibia, versus a short cymbium, 10 retromarginal teeth, smoothly curved embolus wrapped by the conductor, a broad conductor base, and a long cuticular spine on the retrolateral surface of the palpal tibia in C. auriculatus ( Seo, 2017 : p. 114, fig. 1). In addition, leg spination on the femur, tibia and metatarsus differs between the two species ( Table 1 ). FIGURE 4. Cybaeus pseudoauriculatus sp. nov. , male holotype. A. Body, habitus (specimen); B. Chelicera; C. Sternum; D. Palp, prolateral view; E. Ditto, ventral view; F. Ditto, retrolateral view; G. Ditto, dorsal view; H. Patella, dorsal view (Scale bars in mm). Description. Male holotype . Total length 3.32. Carapace: 2.05 long / 1.90 wide, thin brown, head region slightly darker than thoracic region, suboval, cervical and radial furrows distinct, longitudinal fovea needle-shaped, head region slightly elevated, margin of thoracic region with faint blackish brown stripe ( Fig. 4A ). Eyes: AER 0.31, PER 0.49, AME 0.04, ALE 0.09, PME 0.06, PLE 0.08, AME-AME 0.02, AME-ALE 0.01, PME-PME 0.08, PME-PLE 0.07, AME-PME 0.09, ALE-PLE 0.04, all eyes on slightly raised eye tubercles, AER slightly recurved and PER straight from above. Chelicera: 1.06 long / 0.40 wide, thin brown with 3 promarginal teeth and 9 retromarginal teeth (5 small and 4 large) ( Fig. 4B ), lateral condyle present. Endite: 0.56 long / 0.30 wide, thin brown. Labium: 0.40 long / 0.26 wide, pale brown. Sternum: 1.02 long / 1.00 wide, pale brown, subcordate, convex, posterior end pointed protruding deeply between the coxae of leg IV ( Fig. 4C ). Legs: I 7.27 (2.05, 0.65, 1.95, 1.64, 0.98) / II 6.69 (1.87, 0.64, 1.67, 1.58, 0.93) / III 5.13 (1.60, 0.50, 1.10, 1.25, 0.68) / IV 6.95 (1.95, 0.73, 1.72, 1.65, 0.90), leg formula I-IV-II-III, dusky yellowish brown, robust and strongly developed, no annuli, leg supination in Table 1 . Abdomen: 1.55 long / 1.21 wide, dull grayish brown, suboval, no pattern on dorsum, sparsely clothed with long blackish brown hair ( Fig. 4A ). Palp: 2.10 (0.75, 0.25, 0.30, -, 0.80), tibia longer than patella, thumb-like PA blunt and conspicuously protrudent with 4 peg setae ( Fig. 4H ), RTA modified very long and deep, embolus long, slender and curved windingly, shorter than conductor, embolus tip separated from the PCo, conductor large auricle-shaped with broad ladle-like PCo, embolus parallel and separated from the margin of conductor, almost close to the PCo ( Fig. 4D–H ). Distribution. Korea (Mt. Naejangsan, Jeongeup-si, Jeollabuk-do ; Mt. Deogyusan, Muju-gun, Jeollabuk-do ). Only known from the type localities. FIGURE 5. Distribution of four new Cybaeus species in Korea. Remarks. The specimens of Cybaeus pseudoauriculatus were collected in a pitfall trap in mixed forest leaf litter in mountainous terrain (alt. 235 m in Mt. Najangsan and alt. 261 m in Mt. Deogyusan).