Utivarachna chamaeleon Deeleman-Reinhold, 2001

Yamasaki, Takeshi, Hashimoto, Yoshiaki, Endo, Tomoji, Hyodo, Fujio, Itioka, Takao, Mohamed, Maryati & Meleng, Paulus, 2023, Taxonomic study of Bornean species of Utivarachna Kishida, 1940 (Araneae: Trachelidae), with the description of a new species, Zootaxa 5343 (1), pp. 55-73 : 63-65

Utivarachna chamaeleon Deeleman-Reinhold, 2001

Figs 12–15

Utivarachna chamaeleon Deeleman-Reinhold, 2001: 378 , figs 586–592; Dankittipakul, Tavano & Singtripop, 2011: 137, fig. 7 (only a figure of RTA without description).

Type material examined. Holotype ♁ ( RMNH.ARA. 15153), Bako National Park , W. Sarawak, 1.IV.[1985], Coll. Deeleman, leg. C.L. & P. R. Deeleman . Paratypes: 2 ♀ ( RMNH.ARA. 15153), same data. Label data are shown in Fig. 12E .

Diagnosis. In the fukasawana -group, U. chamaeleon is easily distinguished from U. fukasawana and U. ichneumon by short stalk of posterior carapace. Utivarachna chamaeleon is similar to U. galyaniae Dankittipakul, Tavano & Singtripop, 2011 in structures of palp of males and copulatory organs of females. However, in males, U. chamaeleon can be distinguished from U. galyaniae by the shape of its cymbium, which is flatter and apically more slender than that of U. galyaniae . In females, U. chamaeleon has slender bursae, whereas U. galyaniae has more swollen bursae.

Measurements (holotype ♁/ paratype ♀). Carapace length, 2.95/2.80; cephalic width, 1.72/1.50; thoracic width, 2.10/1.96. Diameter of eyes: AME 0.21/0.20; ALE 0.18/0.16; PME 0.13/0.13; PLE 0.18/0.17. Interdistances between eyes: AME–AME 0.03/0.05; AME–ALE 0.05/0.07; ALE–ALE 0.56/0.52; PME–PME 0.22/0.21; PME– PLE 0.33/0.32; PLE–PLE 1.17/1.15; ALE–PLE 0.22/0.25; AME–PME 0.03/0.08. MOA: length 0.35/0.37; anterior width 0.45/0.40; posterior width 0.55/0.50. Clypeus height 0.51/0.46. Abdomen length 2.76/3.05; width 1.70/3.05. Legs: I 10.36 (2.96, 1.10, 2.70, 2.60, 1.00)/8.55 (2.43, 0.97, 2.20, 1.97, 0.98); II 8.63 (2.53, 0.93, 2.12, 2.15, 0.90)/7.88 (2.27, 0.81, 1.95, 1.90, 0.95); III 5.43 (1.57, 0.66, 1.20, 1.42, 0.58)/5.44 (1.55, 0.63, 1.23, 1.45, 0.58); IV 7.11 (2.06, 0.66, 1.60, 2.07, 0.72)/7.13 (2.00, 0.50, 1.72, 2.13, 0.78).

Male ( Fig. 12A–D ). Carapace entirely granulated, dorsally oval, with short posterior stalk; AER almost straight in dorsal view; PER recurved in dorsal view; ocular tubercle accompanied with PLE; lateral margins of carapace strongly constricted between cephalic and thoracic parts; lateral margin of thoracic part undulating. Chelicerae granulated, with six prolateral and six retrolateral teeth. Clypeus with small wedge-shaped projection between chelicerae. Pedicel short. Abdomen oval; dorsum of anterior five-sixths and epigastric area weakly sclerotized. Legs granulated. Legs I and II elongated, with tooth-like cusps located ventrally from patella to tarsus.

Palp ( Fig. 13A–D ). Cymbium pear-shaped, with slender apex; cymbium length about twice its width. Bulb inverted ovoid, prolateral half and subtegulum sclerotized, and retrolateral half partly membranous. Embolus coils inclining dorsally, and covered by cymbium. Sperm duct U-curved in posterior part of bulb, running retrolaterally with weak s-curve from posterior part to embolus. RTA strongly extended, apically developed into semi-transparent plate with apical claw.

Coloration and setation ( Fig. 12A–D ). Carapace brown, covered with fine setae. Chelicerae brown, covered with fine setae; prolateral margin of fang furrow with long setae. Abdomen cream, covered with fine setae; in dorsal view, anterior lateral sides and posterior end tinged with black; sclerotized dorsum and epigastric area amber-colored. Legs covered with fine setae; legs I and II brown to light brown in coxa, trochanter, femur, and patella but cream in tibia, metatarsus, and tarsus; legs III and IV light brown. Distal part of femur, patella, tibia, metatarsus, and tarsus tinged with black or dark-colored rings in all legs.

Female ( Fig. 14A–D ). Carapace and chelicerae almost same as in male. Abdomen oval, with sclerotized epigastric area.

Copulatory organs ( Fig. 15A–C ). Copulatory atrium nearly as long as wide. Copulatory openings located at anterior margin of atrium. Copulatory ducts extending anteriorly with S-curving, and then turning posteriorly with helical coils. Bursae long, elongate oval, extending posteriorly. Spermathecae oval. Fertilization ducts straight, extending from spermathecae posteriorly.

Coloration and setation ( Fig. 14A–D ). Almost same as in male.

Distribution. Central Kalimantan, Sarawak.

Figures

FIGURE 12. Utivarachna chamaeleon Deeleman-Reinhold, 2001, male, holotype (RNMH.ARA.15153). A habitus, dorsal view; B same, ventral view; C cephalic part and chelicerae, frontal view; D leg I, left, prolateral view; E label. Scale bars A–D: 1 mm.

FIGURE 13. Utivarachna chamaeleon, male, holotype (RNMH.ARA.15153). A right palp, retrolateral view; B same, ventral view; C same, prolateral view; D same, dorsal view. Scale bars: 0.50 mm. E—embolus, Sd—sperm duct, St—subtegulum.

FIGURE 14. Utivarachna chamaeleon Deeleman-Reinhold, 2001, female, paratype (RNMH.ARA.15153). A habitus, dorsal view; B same, ventral view; C cephalic part and chelicerae, frontal view; D leg I, left, prolateral view. Scale bars A–D: 1 mm.

FIGURE 15. Utivarachna chamaeleon, female, paratype (RNMH.ARA.15153). A epigyne, ventral view; B internal organs, ventral view; C same, dorsal view. Scale bar: 0.50 mm. Br—bursa, Fd—fertilization duct, S—spermatheca.