Utivarachna ichneumon 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 : 68-70

Utivarachna ichneumon Deeleman-Reinhold, 2001

Figs 20–23

Utivarachna ichneumon Deeleman-Reinhold, 2001: 376 , figs 581–585.

Type material examined. Holotype ♁ ( RMNH.ARA. 15223; Fig. 20E ), Danum Valley F. C., E. Sabah, 6– 16. V.[1991], Coll. Deeleman, leg. C.L. & P. R. Deeleman.

Other material. 1 ♀ ( DV1 _20040910-E5), Danum Valley , Sabah, 10.IX.2004, T. Endo leg.; 1 ♁ ( DV10 _ 20050222-I15), same locality, 22.II.2005 ; 1 ♀ ( DV7 _20050220-O16), same locality, 20.II.2005, leg. R. Oie ; 1 ♀ ( DV53 _20080110-E7), same locality, 10.I.2008, leg. T. Endo. All specimens are deposited at MNHAH .

Diagnosis. See Diagnosis of U. fukasawana .

Measurements (holotype ♁/ ♀). Carapace length 3.95/3.16; cephalic width 1.50/1.37; thoracic width 1.93/1.80. Diameter of eyes: AME 0.18/0.17; ALE 0.16/0.15; PME 0.13/0.13; PLE 0.18/0.17. Interdistances between eyes: AME–AME 0.03/0.03; AME–ALE 0.07/0.07; ALE–ALE 0.56/0.51; PME–PME 0.21/0.20; PME–PLE 0.33/0.27; PLE–PLE 1.15/1.00; ALE–PLE 0.18/0.16; AME–PME 0.06/0.06. MOA: length 0.35/0.32; anterior width 0.40/0.37; posterior width 0.50/0.46. Clypeus height 0.32/0.36. Abdomen length 3.25/2.86; width 1.36/1.83. Legs: I 12.44 (3.35, 1.13, 3.33, 3.50, 1.13)/9.75 (2.73, 0.93, 2.46, 2.53, 1.10); II 10.00 (2.83, 0.82, 2.53, 2.66, 1.16)/8.31 (2.36, 0.73, 2.06, 2.16, 1.00); III 6.35 (1.77, 0.70, 1.42, 1.75, 0.71)/5.51 (1.52, 0.61, 1.20, 1.53, 0.65); IV 8.51 (2.37, 0.68, 2.00, 2.66, 0.80)/7.54 (2.07, 0.61, 1.75, 2.30, 0.81).

Male ( Fig. 20A–D ). Carapace entirely granulated, dorsally oval; posterior stalk slightly shorter than 1/2 carapace length; PER recurved in dorsal view; ocular tubercle accompanied with PLE; thoracic lateral margins undulating. Chelicerae granulated, with five prolateral and five retrolateral teeth. Ventral clypeus margin with small wedge-shaped projection between chelicerae. Pedicel short. Abdomen elongate oval; anterior two-thirds covered with dorsal scutum, weakly developed. Leg I and II elongated, covered with spherical granulation; ventral sides of tibia, metatarsus and tarsus bearing cusps.

Palp ( Fig. 21A–D ). Cymbium slender oval; length almost twice as wide. Bulb oval; posterior half of bulb weakly sclerotized with subtegulum, and anterior half membranous. Embolus coiled; basal part of embolus accompanied by slender sclerotized plate covered by membranous surface of bulb. Sperm duct running from retrolateral side of bulb, U-curved along posterior edge of bulb, then curving to prolateral side. RTA strongly extended, apically developed into semi-transparent plate with apical claw; prolateral corner of semi-transparent plate developed, and anterior margin transforming into short claw.

Coloration and setation ( Fig. 20A–D ). Carapace and chelicerae brown, covered with fine setae. Abdomen cream, with pale brown dorsal scutum, entirely covered with small fine setae. All legs pale brown; leg I darker than others.

Female ( Fig. 22A–D ). Somatic characters almost same as in males, except for abdomen shape and shorter posterior stalk; posterior stalk almost as long as 1/4 carapace length. Chelicerae granulated, with five or six prolateral and five retrolateral teeth. Abdomen oval, without dorsal scutum.

Copulatory organs ( Fig. 23A–C ). Copulatory atrium longer than wide. Copulatory ducts curved into loop anteriorly, then intricately coiled. Bursae long, tube-like shaped, extending posteriorly. Spermathecae globular. Fertilization ducts straight, extending from spermathecae towards posterior.

Coloration and setation ( Fig. 22A–D ). Almost same as in male.

Distribution. Sabah (known only from the type locality).

Remarks. The non-type material examined in the present study was collected from the type locality, Danum Valley, Sabah state. The conspecificity of male and female specimens was based on the long stalk of carapace. Other Utivarachna species with long posterior stalks were not collected from the study site. The female is described here for the first time.

Figures

FIGURE 20. Utivarachna ichneumon Deeleman-Reinhold, 2001, male, holotype (RNMH.ARA.15223). 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–C, 1 mm; D, 0.50 mm.

FIGURE 21. Utivarachna ichneumon, male, holotype (RNMH.ARA.15223). A left palp, prolateral view; B same, ventral view; C same, retrolateral view; D same, dorsal view. Scale bars: 0.50 mm. E—embolus, Sd—sperm duct, St—subtegulum.

FIGURE 22. Utivarachna ichneumon Deeleman-Reinhold, 2001, female (DV53). 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 23. Utivarachna ichneumon, female (DV53). A epigyne, ventral view; B internal organs, ventral view; C same, dorsal view. Scale bars: 0.50 mm. Br—bursa, Fd—fertilization duct, S—spermatheca.