Psechrus cornutus Chen & Yang, 2026, sp. nov.
Authors: Chen, Run, Yang, Zi-Zhong
Type: Taxonomic treatment
Published: 2026-07-24
Keywords: Biodiversity, Taxonomy, Animalia, Arthropoda, Arachnida, Araneae, Psechridae, Psechrus, Psechrus cornutus

<p><b><i>Psechrus cornutus</i> sp. nov.</b></p><p>urn:lsid:zoobank.org:act: B580FF29-BB4B-41E8-A158-15216270E73F</p><p>Figs 1D, 11–14, 19; Table 3</p><p><b>Diagnosis</b></p><p>The new species belongs to the <i>sinensis</i> group and most closely resembles <i>P. discoideus</i> Feng <i>et al.</i>, 2016 (see Feng <i>et al.</i> 2016: 191–193, figs 9–11) in the morphology of the male palp, and both <i>P. discoideus</i> and <i>P. mingshengi</i> sp. nov. in the female epigyne, but can be distinguished by the following combination of characters: palp with the prolateral surface of the conductor base having comparatively sparse granules (vs densely covered with minute granules in <i>P. discoideus</i>); prolateral extension of the conductor less sclerotized and lacking a disc-shaped dilation (vs more sclerotized and disc-shaped); a distinct concavity present at about ⅓ of the conductor length from the base in retrolateral view (vs absent in <i>P. discoideus</i>); embolus broader, more curved, and horn-shaped in retrolateral view (vs narrower and less curved) (Figs 11A, D, 12C); epigyne with the median septum broadly shield-shaped and wider than long, featuring a large central projection (vs subrectangular with lateral shoulders and a broad, trapezoidal outline, giving a ʻstrongman’s back' appearance in <i>P. discoideus</i>; nearly rectangular to subrectangular in <i>P. mingshengi</i>); and spermathecal heads short, arising from the copulatory ducts (vs elongate, arising from the spermathecal bases in the compared species) (Fig. 13B, D).</p><p><b>Etymology</b></p><p>The specific epithet is a Latin adjective, ʻ <i>cornutus</i> ' (-a, -um), meaning ʻhorned'. It refers to the hornlike shape of the embolus. The masculine gender of the adjective agrees with that of the genus <i>Psechrus</i> Thorell, 1878.</p><p><b>Type material</b></p><p><b>Holotype</b></p><p>CHINA • ♂; Yunnan Province, Xi-jing Line, Wuliangshan Town, Nanjian County, Dali Prefecture; 24°47′22″ N, 100°30′49″ E; 1946.2 m a.s.l.; 11 Mar. 2025; Zi-Zhong Yang, Yu-Lin Zheng, Wen-Hao Yin, Run Chen and Hong-Qiang Dai leg.; collection YNNJ-25-0305; DUIER, NJ2501.</p><p><b>Paratypes</b></p><p>CHINA • 5 ♂♂; same data as for holotype; collection YNNJ-25-0305; DUIER NJ2502 – NJ2506 • 5 ♀♀; same data as for holotype; collection YNNJ-25-0305; DUIER NJ2507 – NJ2511 • 1 ♂; Yunnan Province, Duoju Village, Xishelu Township, Chuxiong City, Chuxiong Prefecture; 24°34′18.1″ N, 101°3′44.3″ E; 2150 m a.s.l.; 29 Oct. 2012; Zi-Zhong Yang and Yu-Jie Yang leg.; DUIER, CX15.</p><p><b>Description</b></p><p><b>Male</b> (holotype, DUIER NJ2501; see Figs 11–12)</p><p>MEASUREMENTS. Total length 15.33; prosoma length 6.47, width 4.98; opisthosoma length 8.86, width 3.81.</p><p>EYES. Eye diameters: AME 0.41, ALE 0.39, PME 0.40, PLE 0.38. Eye interdistances: AME–AME 0.13, AME–ALE 0.08, PME–PME 0.15, PME–PLE 0.13, AME–PME 0.28, ALE–PLE 0.16. Clypeus height at AME 0.80.</p><p>PROSOMA. Light brown; posterior two-thirds of lateral margins with a black border. Carapace with a grayish-brown median longitudinal stripe. Fovea longitudinal; radial furrows distinct and pale. Sternum suboval, brown, with a conical gray patch medially; surface with sparse black setae. Chelicerae brown; promargin with 3 teeth, retromargin with 4 teeth. Endites and labium dark brownish; margins covered with dense black setae.</p><p>OPISTHOSOMA. Dorsum dark gray; posterior part with five distinct, pale transverse bars. Lateral sides with several irregular longitudinal stripes. Ventral side brown, with a white median stripe; flanked by two rows of distinct, longitudinally arranged muscle sigilla.</p><p>LEGS. Yellowish-brown; annuli indistinct, without spots. Coxa I with short black spines distally, near trochanter (absent in female). Leg formula: 1423. Measurements of palp and legs as shown in Table 3.</p><p>MALE PALP. Palpal tibia short, with an indistinct retrolateral process; ventrodistally with a tuft of long setae on each side. Femur with a broad ventral apophysis. Conductor membranous and semi-transparent, its base with brown tubercles. Embolus brownish, originating from apex of tegulum, margins with faint transverse ridges. Sperm duct running transversely, nearly horizontal across tegulum, turning at about 70° into posterior tegulum distally.</p><p><b>Female</b> (paratype, DUIER NJ2508; see Figs 13–14)</p><p>MEASUREMENTS. Total length 17.07; prosoma length 7.24, width 5.24; opisthosoma length 9.83, width 6.60.</p><p>EYES. Eye diameters: AME 0.40, ALE 0.42, PME 0.41, PLE 0.42. Eye interdistances: AME–AME 0.14, AME–ALE 0.06, PME–PME 0.14, PME–PLE 0.11, AME–PME 0.27, ALE–PLE 0.17. Clypeus height at AME 0.83.</p><p>SOMATIC CHARACTERS. Median longitudinal stripe on carapace paler, yellowish-brown. Sternum with denser setae than in male. Muscle sigilla on the ventral side of opisthosoma smaller and less distinct than in male. Other characters as in male.</p><p>EPIGYNE. The epigyne is approximately as long as wide. Muscle sigilla and 2–4 slit sense organs situated far from the epigynal field. Median septum distinctly longer than wide, with lateral margins nearly parallel in the anterior half and strongly diverging towards the posterior margin. Lateral lobes indistinct. Copulatory openings distinct and patent, positioned at the anterolateral margins of MS. Copulatory ducts characterized by a distinct reflexed section at their anterior part. Spermatheca subcircular. Spermathecal heads small and knob-like, arising from the mesal base of spermatheca. Fertilization ducts relatively broad, with a width approximately half the diameter of spermatheca, directed postero-laterally.</p><p><b>Distribution</b></p><p>Nanjian County and Chuxiong City, Yunnan Province, China.</p>