Utivarachna angsoduo Dhiya’ulhaq & Dupérré, 2024

Dhiya’Ulhaq, Naufal Urfi, Dupérré, Nadine, Buchori, Damayanti, Scheu, Stefan & Drescher, Jochen, 2024, Four new species of Utivarachna Kishida, 1940 (Araneae: Trachelidae) from Sumatra, Zootaxa 5418 (5), pp. 551-575 : 553-556

Utivarachna angsoduo Dhiya’ulhaq & Dupérré , sp. nov.

Figures 1 , 2

Type material. Holotype ♂: SUMATRA: Jambi Province: Dusun Baru , Air Hitam, Sarolangun (2013_BJ4.2_ AraTrac005N_001), canopy fogging jungle rubber agroforest, 02⁰00’56.8”S, 102⁰45’12.6”E, altitude 64 m, 14.VII.2013, leg. J. Drescher ( MZB).

Etymology. The specific name is taken from Jambi Malay angso duo meaning “two swans”, part of the mythological founding story of Jambi and is a common symbol in Jambi culture. Also alluding to the long, twolobed RTA of the species. Noun in apposition.

Diagnosis. This species belongs to the kinabaluensis -group based on the following characters: carapace wedge-shaped with undulating lateral margins; posterior end of carapace not produced into an elongated stalk ( Fig. 1A ); PER recurved and much longer than AER ( Fig. 1A ); palpal tegulum not enlarged and bulbous ( Fig. 2 ). Males of this species have a similar cephalothorax and abdomen to those of U. trisula sp. nov., but can be distinguished from it (as well as from all other congeners) by the long bifid shape of the RTA ( Figs 2B–E ), each lobe curving in the opposite direction of one another, the ventral lobe additionally with a small spine-like dorsal projection ( Figs 2C, E ) (versus trifid in U. trisula , Figs 15B–E ). Female: unknown

Description. Male (Holotype). Total length 4.90. Carapace length 2.36; width 2.00. Carapace maroon, strongly sclerotized, surface granulated, with granules ending in long white seta, lateral margins undulating, posterior half of carapace almost wedge-shaped with narrowly truncate end; fovea short but distinct; PER longer than AER, both slightly recurved ( Fig. 1A ); clypeus short with slight projection between the chelicerae. Eye diameters:AME 0.13; ALE 0.17; PLE 0.14; PME 0.15. Eye interdistances: AME–AME 0.08; AME–ALE 0.10; ALE–ALE 0.49; PME–PME 0.17; PME–PLE 0.18; ALE–PLE 0.17; AME–PME 0.14; PLE–PLE 0.87. MOA: length 0.41; anterior width 0.33; posterior width 0.48. Clypeus height 0.32. Sternum heart-shaped, colored as carapace, surface granulated ( Figs 1B, D ).

Abdomen length 2.54; width 1.56. Abdomen oval, pale-colored with three pairs of dark patches on the lateral margin, the anterior two pairs rather faint, as well as a darker-shaded cardiac pattern and a pair of small dark patches directly anterior to the spinnerets; most of the dorsal surface of abdomen covered with an orange scutum; ventral side of abdomen sclerotized on the area anterior to the epigastric furrow, projecting a short distance posterior to it on the sides; four longitudinal rows of sclerotized dots present between epigastric furrow and spinnerets.

Legs yellow, covered with long white seta especially on the ventral surface, striated with black bands distally and proximally on tibiae I–IV and femur I, while femora II–IV and metatarsi III–IV with distal bands only; anterior legs stouter and longer than posterior legs; the ventral side of anterior legs filled with leg cuspules from tarsi to tibiae ( Fig. 1C ), metatarsi III and IV distally with comb-like structure distally followed by brush of setae. Leg measurements: leg I 7.46 (2.13, 0.73, 2.11, 1.72, 0.77); leg II 7.55 (2.17, 0.72, 2.05, 1.76, 0.85); leg III 5.19 (1.45, 0.48, 1.26, 1.44, 0.56); leg IV 6.48 (1.72, 0.54, 1.50, 2.09, 0.63).

Male palp ( Fig. 2 ): Cymbium and bulb oval. Sperm duct starting out diagonally then turning at 120° angle, before making narrow U-shaped turn. RTA bifid, ventral lobe canoe-shaped with excavated dorsal surface, long and slightly curved, ending in sharp bifid tip; curved spine-like projection grows dorsally in middle of lobe; dorsal lobe canoe-shaped, with excavated ventral surface, curved more prominently than ventral lobe and in opposite direction, separated from ventral lobe by membranous area, tip rounded, longer and slightly wider than the ventral lobe. Prolateral margins of both lobes narrower than retrolateral margin, giving lobes rebordered appearance when viewed retrolaterally. Embolus long, coiled horizontally. as wide as bulb, looping twice, visible dorsally through the cymbium.

Distribution. Jambi Province, Sumatra (only known from type locality) ( Maps 1 and 2 ).

Remarks. The type specimen was collected by canopy fogging in jungle rubber agroforest, and is considered arboreal.

Figures

FIGURE 1. Utivarachna angsoduo sp. nov., male holotype. A, B Habitus, dorsal view (A), ventral view (B); C Right leg I, prolateral view. D Sternum, ventral view. Scale bars A, B = 1 mm; C, D = 0.5 mm.

MAP 1. Distribution map of Utivarachna species collected in the framework of the 2013 EFForTS project in Jambi Province, Sumatra, Indonesia.

FIGURE 2. Utivarachna angsoduo sp. nov., male holotype. A–E Left palp: A prolateral view; B, D ventral view; C, E retrolateral view. Scale bars = 0.2 mm. Abbreviations: dl, dorsal lobe of RTA; ds, dorsal spine of dorsal RTA lobe; e, embolus; rta, retrolateral tibial apophysis; st, subtegulum; vl, ventral lobe of RTA.

MAP 2. Global distribution map of the Utivarachna species treated in this paper.

FIGURE 15. Utivarachna trisula sp. nov., male holotype. A–E Left palp: A, prolateral view; B, D, ventral view; C, E retrolateral view. Scale bars 0.2 mm. Abbreviations: ac, apical claw of RTA; dl, dorsal lobe of RTA; e, embolus; rta, retrolateral tibial apophysis; st, subtegulum; vl, ventral lobe of RTA.