Rhitymna tangi Quan & Liu, 2012

Jäger, Peter, 2019, Review of the huntsman spider genus Rhitymna Simon, 1897 (Araneae: Sparassidae), Zootaxa 4560 (3), pp. 441-462 : 447

Rhitymna tangi Quan & Liu, 2012

Figs 9–11 , 25–26 , 61

Material examined. LAOS: Oudomxai Province: 1 female ( PJ 3673 ), Lipi provincial protected area, ca. 3.3 km South of Oudomxai, 20°39'39.8"N, 101°59'45.8"E, 731 m elevation, ground, vegetation, by hand, by day, L. Nophaseud leg. 18 April 2011 (SMF).

Additional material. CHINA: Hainan Province: 1 female, Mt Limu [N 19°10'12.00", E 109°45'0.00", 700 m elevation] Yang Zhong leg. 18 May 2015; 1 female, 4 May 1989, Maobin Gu leg. (both CBEE; not examined, illustrations from MSc thesis compared) .

Note. The species was described from Hainan by the male sex only ( Quan & Liu 2012). Material collected and examined by Chinese colleagues in Hainan included one female (see above; collected at the same site of one paratype male: Mt Limu). Unpublished data and illustrations from an MSc thesis have been included in the diagnosis and description presented here. Therefore, it can be stated that the female from northern Laos is conspecific with the specimens found in Hainan. Similar distribution patterns are known from Symphytognathidae : Patu shiluensis Lin & Li, 2009 ( China: Hainan Province, Laos: Champasak Province), or from Sparassidae : Heteropoda simplex Jäger & Ono, 2000 (Northern Laos, Taiwan, Japan: Ryukyu Island).

Diagnosis. Medium-sized to large Sparassidae (body length of females: 16.6–22.8). For males see Quan & Liu (2012). Females are distinguished from those of all other congeners except R. pinangensis and R. verruca in having a strongly sclerotised epigynal plate ( Figs 9–10 ), but distinguished from the two latter species by: 1. Plate longitudinal and slightly wider in anterior half (not or not that strongly elongated and wider in posterior half in R. pinangensis and R. verruca ), 2. Internal duct system relatively simple with first windings situated in anterior half, thus ducts leading to epigastric furrow freely visible (duct system complex and with first windings in posterior half, thus in dorsal view covering large parts of ducts leading to epigastric furrow in R. pinangensis and R. verruca ).

Description. Male: see Quan & Liu (2012).

Female (PJ 3673): PL 9.8, PW 10.5, AW 6.6, OL 13.0, OW 7.3. Eyes: AME 0.52, ALE 0.55, PME 0.36, PLE 0.46, AME–AME 0.46, AME–ALE 0.79, PME–PME 0.86, PME–PLE 1.47, AME–PME 0.46, ALE–PLE 0.55, clypeus height at AME 0.32, clypeus height at ALE 0.21. Cheliceral furrow with 3 promarginal, 4 retromarginal teeth, without denticles. Retromargin of chelicerae close to fang base with 17–19 bristles. Spination: Palp: 130, 0 0 2, 1121, 1012; legs: femur I–III 323, IV 320; patella I–III 101, IV 100; tibia I–II 2226, III–IV 2126; metatarsus I–II 2024, III 2025, IV 3025. Leg formula: 2143. Measurements of palp and legs: Palp 12.8 (4.1, 2.0, 2.6, -, 4.1), I 46.8 (12.3, 5.9, 12.6, 12.6, 3.4), II 48.4 (13.3, 5.6, 13.2, 12.7, 3.6), III 32.3 (10.1, 4.1, 8.9, 6.7, 2.5), IV 38.6 (11.6, 4.0, 10.6, 9.3, 3.1). Metatarsi III–IV with ventro-distal spine within scopula (sparse in Mt IV).

Copulatory organ as in diagnosis ( Figs 9–11 ). Epigynal field longer than wide, with several small muscle attachment points laterally and one pair of slit sensilla within epigynal field. Epigynal plate with rounded incision at posterior margin. Copulatory openings situated antero-medially, first windings of internal duct system kidneyshaped, ducts leading to epigastric furrow anterior-laterally with glandular appendages.

Colouration ( Figs 25–26 ). Yellowish- to deep reddish-brown. Prosoma dorsally deep reddish-brown, with black fovea, marbled pattern and dense pattern of elongates muscle sigilla. Eye region anteriorly lighter close to lateral eyes. Chelicerae deep reddish-brown. Sternum reddish-brown with 3 pairs of humps laterally and 1 fused hump posteriorly, gnathocoxae and labium brown, distally yellowish-brown. Coxae brown with marbled pattern. Legs reddish- (proximally) to deep reddish-brown (distally). Opisthosoma yellowish-brown with typical tuningfork pattern and several dots dorsally, ventrally with 4 longitudinal light lines in darker median field.

Variation. Females (n=1; data from unpublished MSc Thesis) with PL 6.9, OL 9.7.

Distribution. China: Hainan Province, Laos: Oudomxai Province (first record) ( Fig. 61 ).

Figures

FIGURE 61. Records of Rhitymna species currently known (World Spider Catalog 2019 and works cited therein, records in this paper). Species with larger distribution ranges: stars—R. verruca, light triangles—R. plana, light squares—R. pinangensis. Inset: Sri Lanka.

FIGURES 6–11. 6–8 Rhitymna gerdmangel spec. nov., female paratype from Mae Hong Son Prov., Thailand; 9–11 Rhitymna tangi, female from Oudomxai Prov., Laos. 6, 9 Epigyne, ventral; 7, 10 Vulva, dorsal; 8, 11 Schematic course of internal duct system, dorsal. EF—epigynal field, FD—fertilisation duct, FW—first winding of internal duct system, GA—glandular appendage, MP—median plate, OB—oval bend of internal duct system, SS—slit sensillum.

FIGURES 16–27. Rhitymna spp., habitus (16–23, 25–27 in ethanol; 24 alive). 16–19 Rhitymna gerdmangel spec. nov. from Mae Hong Son Prov., Thailand; 20–24 Rhitymna plana, from Tuyen Quang Province, Vietnam; 25–26 Rhitymna tangi, from Oudomxai Prov. Laos; 27 Rhitymna cursor, holotype from Singapore (16–17, 20–21 males, 18–19, 22–27 females).