Ryuthela owadai, ONO, 1997

RYUTHELA OWADAI ONO, 1997 View in CoL

Ryuthela owadai Ono, 1997, p. 155 View in CoL , figs 15–18 (description of male); Ono, 2001, p. 151, figs 1–3 (description of female); Ono, 2009, p. 80, figs 19–25; Schwendinger & Ono, 2011, p. 616, figs 48–50.

Holotype: Male deposited at NSMT (NSMT-Ar 3459), from Aharen , c. 100 m a.s.l., Tokashikijima island, Okinawa Prefecture, Japan, 11 October 1990, by M. Owada; examined.

Other material examined: Fourteen females and five juveniles [XUX-2012-(404–416, 418– 420/422/426/429A/ 430)], collected at Aharen , Tokashikijima island, Okinawa Prefecture, Japan, 26.17°N, 127.35°E, 50 m a.s.l., 22 December 2012, by D. Li, F. X. Liu and X. Xu GoogleMaps .

Diagnosis: Females of R. owadai differ from all other Ryuthela species by the relative length of receptacular clusters (these are slightly longer than wide; Fig. 13A– L); the female genitalia are morphologically similar to R. sasakii , but the length of the receptacular clusters is shorter than that of R. sasakii . Moreover, R. owadai can also be diagnosed from R. sasakii by the following unique nucleotide substitutions in the standard DNA barcode alignment: T (10), A (22), A (43), C (163), C (211), C (239), T (241), T (271), T (322), C (343), T (352), T (361), T (364), T (367), C (370), T (415), T (454), A (470), T (502), T (541), G (544), C (601), C (610), C (622).

Description: Female. Carapace and opisthosoma yellow brown; tergites darker brown; sternum narrow, nearly twice as long as wide; a few long pointed hairs running over ocular mound in a longitudinal row; chelicerae robust with promargin of cheliceral groove containing 12–14 vestigial denticles of variable size; legs with strong hairs and spines; opisthosoma with 12 tergites; 7 spinnerets. Measurements: BL 6.80– 10.50, CL 3.50–5.18, CW 2.98–4.20, OL 3.48–5.85, OW 2.60–4.20; ALE> PLE> PME> AME; palp 5.98 (2.05 + 1.08 + 1.30 + 1.55), leg I 8.63 (2.50 + 1.43 + 1.55 + 1.50 + 1.65), leg II 8.29 (2.43 + 1.50 + 1.45 + 1.73 + 1.18), leg III 8.59 (2.40 + 1.37 + 1.35 + 2.15 + 1.32), leg IV 11.89 (2.97 + 1.78 + 2.10 + 3.21 + 1.83).

Female genitalia. A pair of receptacular clusters with the basal parts separated or fused together and with the distal part heart shaped ( Fig. 13D, F); the opening part of receptacular clusters is located at the ventral part of bursa copulatrix, but visible in the dorsal view ( Fig. 13A–L).

D i s t r i b u t i o n: To k a s h i k i j i m a i s l a n d, O k i n a wa Prefecture, Japan.

Remarks: Tanikawa (2013a) considered R. owadai as synonym of R. sasakii based on the lack of distinct morphology to distinguish them. Although we only collected females whose genitalia are highly variable as in other Ryuthela , the results from other data sources support the validity of R. owadai .