Cycloperipsocus hamatus, Cao & Liu, 2025

Cao, Leran & Liu, Xingyue, 2025, A review of the bark louse genus Cycloperipsocus Li, 1993 (Psocodea: Peripsocidae) with description of five new species, Zootaxa 5620 (2), pp. 201-229 : 210-211

Cycloperipsocus hamatus sp. nov.

( Figs 10–13 )

Diagnosis. Postclypeus with faint brown stripes. Forewing Mb cream. Phallosome rounded at apex. Paramere with its tip expanded into fan-shaped, inner process relatively long and hook-like.

Description. Male ( Figs 10–11 ). Coloration (preserved in 95% ethanol). Head pale brown; vertex with dark-colored markings; gena reddish-brown at bottom half; postclypeus light brown with indistinct brown stripes; anteclypeus and labrum brown; maxillary pale with reddish-brown markings along distal margin of each segment; ocelli white with reddish-brown spots, ocellar region cream white; compound eyes black. Antennae: scape pale brown, pedicel and flagellum missing. Thorax brown; scutellum, postnotum of mesothorax and scutellum of metathorax pale cream. Legs pale cream; fore tibiae and tarsi brown; mid and hind femora, tibiae pale brown at middle part; pretarsi brown. Wings cream white with taupe markings as in Figs 10C–D ; forewing Mb cream, a pale spot present at distal margin of cell M2. Pregenital abdominal segments cream, with reddish-purple markings on ventral and lateral sides. Terminalia grayish brown, a light brown spot present in the middle of clunium.

Morphology. Clunium slightly extended, without any process or serrations. Epiproct semicircular. Paraproct ovoid, inner margin with a small process; posterior lobe ovate. Hypandrium simple. Phallosome ( Figs 11C–H ) basally closed, slightly constricted in the middle; aedeagal arch rounded at apex, distal 1/3 hood-like; parameres strong, distally expanded into fan-shaped, a pair of hook-like inner process present medially. Penis bulb consists of a middle thorn and a pair of lateral lobes; lateral lobe expanded into hemispheric shape, serrated along outer margin, inner margin with a long spine pointed forward.

Measurements (in μm) (1 male). B: 1163, IO: 117, d: 169, IO/d: 0.69, FWL: 1877, FWW: 840, HWL: 1428, HWW: 545, t1: 149, t2: 60. Number of ctenidia on hind first tarsomere: 13.

Female ( Figs 12–13 ). Coloration (preserved in 95% ethanol). Head: vertex pale cream with faint markings; frons cream white, with a pale brown area around ocellar region and a pair of brown spots between postclypeus and compound eyes; gena cream white, bottom 1/3 brown, a brown subtriangular spot present rear to compound eye. Antennae cream white, flagellum darkening toward apex. Other parts generally the same as male except pterostigma dark brown at distal half.

Morphology. Epiproct semicircular. Paraproct subtriangular. Subgenital plate ( Figs 13D–E ) with pigmented area V-shaped; pigmented arm broadening toward end, somewhat bifurcate at apex; egg guide short, constricted at base, outer and distal margin folded inward. Gonapophyses ( Fig. 13F ): ventral valve broadened with membrane in middle, narrowing toward apex; dorsal valve broad, oblong, about 1.5 times as long as its width, with a row of setae along distal margin; external valve rectangular, about half the length of dorsal valve, slightly setose.

Measurements (in μm) (1 female). B: 1464, BW: 2175, IO: 244, d: 96, IO/d: 2.53, f1: 129, FWL: 1906, FWW: 789, HWL: 1503, HWW: 527, t1: 128, t2: 59. Number of ctenidia on hind first tarsomere: 9.

Material examined. Holotype male, China: Fujian, Xiamen, Tong’an, Jinguang Lake , 400 m, 4.IV.2019, Yuchen Zheng ( CAU) . Paratype: 1 female, China: Xizang, Zayu, Songrao Village , 2489 m, 19.VI.2019, Rongrong Shen & Yingnan He ( CAU) .

Known distribution. China (Fujian, Xizang).

Etymology. The specific epithet refers to the hook-like inner process on paramere.

Remarks. This new species closely resembles C. pangi and can be distinguished from it by the hook-like inner process on the male paramere and the apically broadened pigmented arms on the female subgenital plate.

Figures

FIGURE 10. Cycloperipsocus hamatus sp. nov., holotype male.(A) habitus, lateral view; (B) habitus, dorsal view; (C) forewing; (D) hindwing; (E) head, frontal view; (F) head, dorsal view.

FIGURE 11. Cycloperipsocus hamatus sp. nov., holotype male, genitalia. (A) clunium, epiproct and paraproct, dorsal view; (B) hypandrium, ventral view; (C–D) phallosome, lateral view; (E–F) phallosome dorsal view; (G) phallosome, caudal view; (H) penis bulb, dorsal view.

FIGURE 12. Cycloperipsocus hamatus sp. nov., paratype female. (A) habitus, lateral view; (B) habitus, dorsal view; (C) forewing; (D) hindwing; (E) head, frontal view; (F) head, dorsal view.

FIGURE 13. Cycloperipsocus hamatus sp. nov., paratype female, genitalia. (A) dorsal view; (B) lateral view, subgenital plate removed; (C) caudal view, subgenital plate removed; (D) subgenital plate, ventral view; (E) subgenital plate, lateral view; (F) gonapophyses, lateral view.