Trematocephalus cristatus
Creators: name: Irfan, Muhammad
name: Zhou, Gu-Chun
name: Peng, Xian-Jin
name: Zhang, Zhi-Sheng
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Linyphiidae
Trematocephalus
Trematocephalus cristatus

description: Trematocephalus cristatus (Wider, 1834)
(冠Ɩ头Ŀe)
Figures 258–261, 310
Theridion cristatum Wider, 1834: 224, pl. 15, fig. 9 (♂ ♀).
Trematocephalus cristatus Chyzer & Kulczyński 1894: 95, pl. 4, fig. 5 (♂ ♀); Lecigne 2018: 71, fig. 9B (♂). For full list of publications and synonyms concerning this species see WSC (2024).
Material examined. 2♂ 2♀, CHINA, Guizhou Prov.: Tongren City, Wenbi Feng, 27.719467°N, 109.16795°E, 476 m, 26.VII.2014, C. Wang et al. leg.
Description. Male (Figs 261A–C). Total 1.84 long; carapace 0.89 long, 0.69 wide, orange. Cephalic region with cephalic lobe extending forward, almost covering the PMEs. Carapace yellow; cephalic region slightly elevated; fovea, cervical and radial grooves distinct. Clypeus 0.18 high. Chelicerae with four promarginal and four retromarginal teeth. Legs long, yellow, covered with fine setae. Sternum longer than wide, brownish grey with microsetae. Eye sizes and interdistances: AME 0.05, ALE 0.06, PME 0.05, PLE 0.06, AME–AME 0.03, PME–PME 0.09, AME–ALE, 0.02, PME–PLE 0.03, ALE–ALE 0.21, PLE–PLE 0.24, ALE–PLE contiguous, AME–PME 0.08. Length of legs: I 2.58 (0.76, 0.85, 0.58, 0.39), II 2.46 (0.74, 0.81, 0.54, 0.37), III 2.05 (0.63, 0.60, 0.50, 0.32), IV 2.70 (0.77, 0.86, 0.66, 0.41). Tibial spine formula: 2-2- 1-1. TmI 0.62 and TmIV absent. Opisthosoma 1.07 long, 0.69 wide, oval, blackish brown, densely covered with fine setae, ventral side brown.
Palp (Figs 258A–D, 259A–D): Femur unmodified, almost as long as patella, tibia and cymbium. Patella as long as tibia, ventrally grooved. Tibia conical, distal end broad, with two retrolateral and one dorsal trichobothria, dorsal tibial apophysis (DSA) unmodified; cymbium unmodified; proximal part of paracymbium (PC) with thick setae, distal arm wing-shaped, retrolateral margin of distal arm with well-developed broad projection, almost touches the tailpiece of embolic division; protegulum (PT) long, bifurcated at the base, extending above the cymbium; distal suprategular apophysis (DSA) broad, unmodified, most of it covered by the embolic division. Embolic division relatively simple, with radix (R) giving rise tailpiece (TP) and embolus, embolic membrane (EM) attached to embolus; embolus (E) long, filiform.
Female (Figs 261D, E): Total 2.02 long; carapace 0.91 long, 0.67 wide; opisthosoma 1.17 long, 0.77 wide. Eye sizes and interdistances:AME 0.04, ALE 0.03, PME 0.06, PLE 0.03, AME–AME 0.04, PME–PME 0.06, AME– ALE, 0.03, PME–PLE 0.03, ALE–ALE 0.23, PLE–PLE 0.27, ALE–PLE 0.01, AME–PME 0.04. Clypeus 0.17 high. Chelicerae with 5 promarginal and 5 retromarginal teeth. Legs long, yellow, covered with fine setae. Length of legs: I 2.65 (0.79, 0.87, 0.58, 0.41), II 2.62 (0.76, 0.86, 0.61, 0.39), III 2.37 (0.66, 0.71, 0.57, 0.37), IV 2.90 (0.85, 0.91, 0.75, 0.39). Tibial spine formula: 2-2-1-1. TmI 0.63 and TmIV absent. All other characters same as in male, except black in color.
Epigyne (Figs 260A–C): Ventral plate (VP) wider than long, posteriorly attached with dorsal plate (DP). Copulatory opening (CO) present at the junction of dorsal and ventral plates posteriorly; copulatory ducts (CD) form three coils mid dorsally before entering the spermathecae; spermathecae (S) elongated extending anteriorly; fertilization ducts (FD) extending mesally.
Distribution. Europe, Turkey, Caucasus, Russia (Europe to Far East), Iran, China (Guizhou and Hubei Provinces, Fig. 310).
description: Published as part of Irfan, Muhammad, Zhou, Gu-Chun, Peng, Xian-Jin & Zhang, Zhi-Sheng, 2025, Survey of Linyphiidae spiders (Arachnida: Araneae) from some Oriental Regions of China, pp. 1-248 in Megataxa 15 (1) on pages 196-200, DOI: 10.11646/megataxa.15.1.1, http://zenodo.org/record/14985176