taxonID	type	description	language	source
E54687B5FFC4FF9AA8D2BFA3FF38FC69.taxon	diagnosis	Diagnosis. The genus can be identified by the unique combination of mandibular characters alone: ventral ridge tooth 2 absent on both mandibles (ventral ridge tooth 1 present as a simple tooth in the medial portion of the left mandible); and basal extra teeth present near base of mandibles. In addition, the genus can be distinguished by the following character combination that can be easily seen when mandibles are closed: semimembranous extension on labrum present; protarsi expanded; pronotum widest at the first third; and distinct accessory ridges on tergites present.	en	Hu, Fang-Shuo, Solodovnikov, Alexey (2026): The second species of Cyanocypus He & Zhou (Coleoptera: Staphylinidae: Staphylininae) with remarks on the systematic position of the genus. Zootaxa 5831 (2): 295-300, DOI: 10.11646/zootaxa.5831.2.12, URL: https://doi.org/10.11646/zootaxa.5831.2.12
E54687B5FFC4FF9AA8D2B94AFA9EFA61.taxon	description	(Fig. 1)	en	Hu, Fang-Shuo, Solodovnikov, Alexey (2026): The second species of Cyanocypus He & Zhou (Coleoptera: Staphylinidae: Staphylininae) with remarks on the systematic position of the genus. Zootaxa 5831 (2): 295-300, DOI: 10.11646/zootaxa.5831.2.12, URL: https://doi.org/10.11646/zootaxa.5831.2.12
E54687B5FFC4FF9AA8D2B94AFA9EFA61.taxon	materials_examined	Material examined. N-VIETNAM: 1 female, La Pan Tan, Yen Bai, 21.80, 104.18, 1200 – 2000 m, IV- 2024, leg. local collector / Project: Revision of Ocypus group DNA Voucher specimen: FS 503 (NHMD); 1 male, same locality, but V- 2024 / Project: Revision of Ocypus group DNA Voucher specimen: FS 364 (NHMD); 3 males, same locality, but IV. 2025 (FSHC, TARI).	en	Hu, Fang-Shuo, Solodovnikov, Alexey (2026): The second species of Cyanocypus He & Zhou (Coleoptera: Staphylinidae: Staphylininae) with remarks on the systematic position of the genus. Zootaxa 5831 (2): 295-300, DOI: 10.11646/zootaxa.5831.2.12, URL: https://doi.org/10.11646/zootaxa.5831.2.12
E54687B5FFC4FF9AA8D2B94AFA9EFA61.taxon	distribution	Distribution. The species was described from Yunnan Province, China. Our records from northern Vietnam substantially expand the known distribution for this species and represent a new country record.	en	Hu, Fang-Shuo, Solodovnikov, Alexey (2026): The second species of Cyanocypus He & Zhou (Coleoptera: Staphylinidae: Staphylininae) with remarks on the systematic position of the genus. Zootaxa 5831 (2): 295-300, DOI: 10.11646/zootaxa.5831.2.12, URL: https://doi.org/10.11646/zootaxa.5831.2.12
E54687B5FFC4FF9AA8D2B94AFA9EFA61.taxon	discussion	Remarks. Specimens from Vietnam exhibit a slightly shorter and more truncated median lobe of the aedeagus (Figs 1 C, D, F) compared to the type series from China illustrated by He & Zhou (2020). However, all other characters are consistent with the type series. We therefore consider this difference as intraspecific variation.	en	Hu, Fang-Shuo, Solodovnikov, Alexey (2026): The second species of Cyanocypus He & Zhou (Coleoptera: Staphylinidae: Staphylininae) with remarks on the systematic position of the genus. Zootaxa 5831 (2): 295-300, DOI: 10.11646/zootaxa.5831.2.12, URL: https://doi.org/10.11646/zootaxa.5831.2.12
E54687B5FFC4FF9FA8D2BB42FC06FA89.taxon	description	(Fig. 2)	en	Hu, Fang-Shuo, Solodovnikov, Alexey (2026): The second species of Cyanocypus He & Zhou (Coleoptera: Staphylinidae: Staphylininae) with remarks on the systematic position of the genus. Zootaxa 5831 (2): 295-300, DOI: 10.11646/zootaxa.5831.2.12, URL: https://doi.org/10.11646/zootaxa.5831.2.12
E54687B5FFC4FF9FA8D2BB42FC06FA89.taxon	materials_examined	Material examined. Holotype: male, N-VIETNAM: La Pan Tan, Yen Bai, 21.80, 104.18, 1200 – 2000 m, VI. 2025, leg. Local collector (NHMD). Paratypes: 3 females, same locality as the holotype but IV. 2025 (FSHC; NHMD; TARI); 2 females, Nam Co, Yen Bai, 21.85, 104.31, 800 – 2400 m, IV- 2024, leg. local collector (FSHC; NHMD); 1 female, same data as the previous ones / Project: Revision of Ocypus group DNA Voucher specimen: FS 365 (NHMD); 1 female, Huyen Mu Cang Chai, Yen Bai, La Pan Tan, 21.80, 104.19, ca. 2000 m, v. 2024, leg. local collector (NHMD).	en	Hu, Fang-Shuo, Solodovnikov, Alexey (2026): The second species of Cyanocypus He & Zhou (Coleoptera: Staphylinidae: Staphylininae) with remarks on the systematic position of the genus. Zootaxa 5831 (2): 295-300, DOI: 10.11646/zootaxa.5831.2.12, URL: https://doi.org/10.11646/zootaxa.5831.2.12
E54687B5FFC4FF9FA8D2BB42FC06FA89.taxon	diagnosis	Diagnosis. The species can be diagnosed by the head and pronotum being brown with a bronze to purplish luster; elytra black with golden setae; vertex of head with punctures becoming strigose (fusing and forming short channels); and tergites III – V with distinct arcuate additional medio-transversal carina.	en	Hu, Fang-Shuo, Solodovnikov, Alexey (2026): The second species of Cyanocypus He & Zhou (Coleoptera: Staphylinidae: Staphylininae) with remarks on the systematic position of the genus. Zootaxa 5831 (2): 295-300, DOI: 10.11646/zootaxa.5831.2.12, URL: https://doi.org/10.11646/zootaxa.5831.2.12
E54687B5FFC4FF9FA8D2BB42FC06FA89.taxon	description	Description. FL: 8.5 – 9.5 mm (average 8.75 mm); WL: 14 – 16 mm (average 14.8 mm). Habitus (Figs 2 A, B). Head, pronotum, and elytra brown with bronze to purplish luster. Head densely punctate; vertex with strigose punctation, other punctures variable, from rounded to irregular. Antennae black, antennomeres I – X slightly longer than wide, last segment about as long as wide. Pronotum densely punctate, with regular, rounded punctures; with distinct transverse pale stripe of setae at midlength; with impunctate midline wide and distinct. Elytra and scutellum densely covered with golden setae; with a pair of paler setae near mediolateral margin, close to elytral lateral macroseta 2. Tergites black; tergite II impunctate; tergites III – V each with accessory basal ridges and distinct arcuate additional medio-transversal carina. Tergites III – V each with paired patches of golden and white setae laterally, extending to paratergites; black setae on tergite III sparse medially, but denser on tergites IV and V, and covering most of tergite VI. Tergite VII densely covered with white setae basally, mixed with golden setae posteriorly, and with black setae along posterior margin. Tergite VIII with sparse golden setae and a distinct pale apical seam of palisade setae. Sternites III – VIII black, sparsely covered with white setae that get slightly denser on sternites V and VII – VIII; sternite V with sparse white setae basally and denser black setae posteriorly. Male sternites VII and VIII each with a moderately deep, subtriangular emargination at midpoint of posterior margin, slightly deeper on sternite VIII. Aedeagus (Figs 2 C – F) slender, asymmetrical; median lobe parallel-sided in basal portion in parameral view, gradually narrowing apically, apex rounded. Paramere slender, slightly twisted to the left, gradually narrowing apically, apex rounded; underside with numerous sensory pegs forming an apical cluster, extending basally along both lateral margins. Females on average slightly more robust than males, but otherwise no marked sexual dimorphism. Comparison. Cyanocypus aeneus sp. nov. can be distinguished from C. leukos by: the head and pronotum metallic brown to purple (metallic blue in C. leukos); elytra black with golden setae (metallic blue with black setae in C. leukos); vertex of head with strigose punctation (uniformly rounded punctures in C. leukos); and presence of distinct arcuate additional medio-transversal carina on tergites III – V (no additional medio-transversal carina on tergites III – V in C. leukos).	en	Hu, Fang-Shuo, Solodovnikov, Alexey (2026): The second species of Cyanocypus He & Zhou (Coleoptera: Staphylinidae: Staphylininae) with remarks on the systematic position of the genus. Zootaxa 5831 (2): 295-300, DOI: 10.11646/zootaxa.5831.2.12, URL: https://doi.org/10.11646/zootaxa.5831.2.12
E54687B5FFC4FF9FA8D2BB42FC06FA89.taxon	distribution	Distribution. The species is known from the mountainous area around La Pan Tan and Nam Co in Yen Bai Province, northern Vietnam.	en	Hu, Fang-Shuo, Solodovnikov, Alexey (2026): The second species of Cyanocypus He & Zhou (Coleoptera: Staphylinidae: Staphylininae) with remarks on the systematic position of the genus. Zootaxa 5831 (2): 295-300, DOI: 10.11646/zootaxa.5831.2.12, URL: https://doi.org/10.11646/zootaxa.5831.2.12
E54687B5FFC4FF9FA8D2BB42FC06FA89.taxon	etymology	Etymology. The specific epithet aeneus is a Latin adjective of masculine gender in genitive case for “ bronze ” or “ bronze-colored, ” referring to the metallic bronze luster of the species.	en	Hu, Fang-Shuo, Solodovnikov, Alexey (2026): The second species of Cyanocypus He & Zhou (Coleoptera: Staphylinidae: Staphylininae) with remarks on the systematic position of the genus. Zootaxa 5831 (2): 295-300, DOI: 10.11646/zootaxa.5831.2.12, URL: https://doi.org/10.11646/zootaxa.5831.2.12
