Pholcus incheonensis Lee & Lee, 2021

Pholcus incheonensis Lee & Lee View in CoL , sp. nov.

Figs. 1E–F View FIGURE 1 , 2E–F View FIGURE 2 , 7 View FIGURE 7 , 8 View FIGURE 8 , 14A–L View FIGURE 14 , 16 View FIGURE 16

Type material. Holotype: ♂, SOUTH KOREA : Incheon: Ganghwa-gun, Hwado-myeon, Jeongsusa temple in Mt. Manisan , Ganghwado Is. (37˚36’24”N, 126˚26’45”E), 29 Jun. 2012, D.Y. Choi leg. ( NIBR) . Paratypes: 5♂ 2♀, same data as for holotype ( KISE) ; 3♀, same data as for holotype ( KNU) ; 5♂ 6♀, Gyeyang-gu, Gyesan-dong, Mt. Gyeyangsan (37˚33'00"N, 126˚43'22"E), 29 Jun. 2014, D.Y. Choi leg. ( KISE) ; 1♂ 1♀, ditto ( KNU) .

Etymology. The specific epithet is derived from the type locality, Incheon.

Diagnosis. This species can be distinguished from the other congeners by the combination of following characteristics: Male—procursus tip with widely bifurcated dorsal process, consisted of short, stout and sharp branch, directed prolaterally and long, slender and sharp branch, directed distally; uncus polygonal, outer margin extended trapezoidally. Female—epigynal anterior plate strongly protruded, with angled margin; epigynal posterior plate and knob reduced and obscured by anterior plate; internal genitalia with triangular anterior arch and prominent median septum bordered pore plates; posterolateral portion of internal genitalia strongly curved, with anterior round projection. This is the only known species of the Pholcus phungiformes -group whose female internal genitalia has a prominent median septum.

Description. Male (holotype). Habitus as in Fig. 1E View FIGURE 1 . Total length 5.9. Prosoma 1.6 long, 1.5 wide. Diameter of AME 100 µm, ALE 170 µm, PME 180 µm, PLE 180 µm. AME–AME 40 µm, PME–PME 200 µm, PME–ALE 60 µm. Chelicera ( Fig. 2E–F View FIGURE 2 ) with round proximo-lateral apophysis with hump distally, dull-pointed frontal apophysis and dorsally curved slender distal apophysis longer than proximo-lateral apophysis; Opisthosoma 3.9 long, 1.6 wide. Leg Ⅰ 49.9 (12.4 + 0.8 + 13.0 + 21.2 + 2.5), leg II 33.6 (9.2 + 0.7 + 8.7 + 13.4 + 1.6), leg III 22.8 (6.5 + 0.7 + 5.7 + 8.7 + 1.2), leg IV 30.2 (8.6 + 0.7 + 7.7 + 11.7 + 1.5). Ratio of leg Ⅰ (16.3: 1.0: 17.0: 27.9: 3.3), leg II (13.0: 1.0: 12.2: 19.0: 2.2), leg III (9.6: 1.0: 8.4: 12.8: 1.8), leg IV (12.3: 1.0: 11.0: 16.7: 2.1). Leg formula 1243. Tibia Ⅰ L/d 80. Retrolateral trichobothrium on tibia Ⅰ at 5% proximally. Tarsus Ⅰ with 31 pseudosegments. For the other somatic features see description of the species-group above. Palp ( Fig. 7 View FIGURE 7 ). Trochanter apophysis ( Fig. 7A–B View FIGURE 7 ) longer than femur, slender, distinctly elongated and strongly curved retrolaterally, distally hooked, blunt, proximo-retrolaterally with tubercle; femur ventrally swollen, with sharp edge; tibia with prolatero-ventral tubercle; procursus ( Fig. 7B View FIGURE 7 ) orangish brown, slightly sinuated dorsally, with prominent ventral knee; dorso-subdistal portion of procursus linear, with one short hair and two spines ( Fig. 7C View FIGURE 7 ); procursus tip ( Fig. 7C–E View FIGURE 7 ) with two distinct ridges retrolaterally, widely bifurcated dorsal process (short, stout and sharp branch, directed prolaterally and long, slender and sharp branch, directed distally) (arrowed 1, 2 in Fig. 7D View FIGURE 7 ), distally hooked membranous process (arrowed 3 in Fig. 7D View FIGURE 7 ), and round ventral process (arrowed in Fig. 7E View FIGURE 7 ); genital bulb round, pale yellow; uncus ( Fig. 7F View FIGURE 7 ) dark brown, polygonal, outer distal margin extended trapezoidally, with many tiny scales; pseudoappendix ( Fig. 7G View FIGURE 7 ) tiny and pointed, hidden by uncus prolaterally; embolus ( Fig. 7G View FIGURE 7 ) pale yellow, slender and distally fringed, weakly sclerotized, twice as long as uncus.

Female (one of paratypes from the same locality as holotype). Habitus as in Fig. 1F View FIGURE 1 . Total length 5.8. Prosoma 1.6 long, 1.4 wide. Diameter of AME 90 µm, ALE 180 µm, PME 160 µm, PLE 170 µm. AME–AME 80 µm, PME–PME 210 µm, PME–ALE 50 µm. Opisthosoma 3.8 long, 1.9 wide. Leg Ⅰ 38.0 (9.4 + 0.8 + 9.6 + 16.0 + 2.2), leg II 25.9 (6.8 + 0.8 + 6.5 + 10.3 + 1.5), leg III 18.8 (5.5 + 0.6 + 4.6 + 7.0 + 1.1), leg IV 25.3 (7.3 + 0.7 + 6.3 + 9.6 + 1.4). Ratio of leg Ⅰ (12.5: 1.0: 12.8: 21.3: 3.0), leg II (9.0: 1.0: 8.7: 13.7: 2.0), leg III (9.3: 1.0: 7.8: 11.8: 1.9), leg IV (11.2: 1.0: 9.7: 14.8: 2.1). Leg formula 1243. Tibia Ⅰ L/d 56. For the other somatic features see description of the species-group above. Epigyne ( Fig. 8A–C View FIGURE 8 ). Anterior plate strongly protruded, half as high as epigyne length, with angled posterior margin; anterior cuticle sclerotized; posterior plate and knob reduced and obscured by anterior plate. Internal genitalia ( Fig. 8D View FIGURE 8 ). Anterior arch triangular, with prominent median vertical septum bordered pore plates; genital valve inverted U-shaped; posterolateral portion concave, with blunt anterior projection; pore plates triangular, close together.

Variation. Males. Prosoma width: 1.4–1.9 (mean 1.6), tibia Ⅰ: 9.7–13.7 (mean 12.3) (n=10).An intrapopulational variation was observed on the length of the longer branch of the bifurcated dorsal process of procursus tip; some with small teeth on the shorter branch of the bifurcated dorsal process of procursus tip proximally ( Fig. 14A, D, G, J View FIGURE 14 ).

Females. Prosoma width: 1.4–1.9 (mean 1.6), tibia Ⅰ: 8.1–9.7 (mean 9.1) (n=10). An intrapopulational variation was observed on the shapes of pore plates of internal genitalia (triangular or oblong) ( Fig. 14C, F, I, L View FIGURE 14 ), but the epigynal shapes were largely consistent ( Fig. 14B, E, H, K View FIGURE 14 ).

Habitat information. This species was found on rock walls and road drains in mountainous regions.

Distribution. Korea (Ganghwado Is. and Mt. Gyeyangsan, Incheon) ( Fig. 16 View FIGURE 16 )