Trilacuna nangunhe Dai & Tong, 2025

Dai, Chengzhi, Yang, Tong, Tong, Yanfeng & Yang, Zizhong, 2025, Two new species of the genus Trilacuna Tong & Li, 2007 (Araneae, Oonopidae) from the Nangunhe Nature Reserve, Yunnan Province, China, Biodiversity Data Journal 13, pp. e 175820-e 175820 : e175820-

Trilacuna nangunhe Dai & Tong sp. nov.

Materials

Type status: Holotype. Occurrence: catalogNumber: SYNU-F-4864 ; recordedBy: Jimeng Ma; individualCount: 1; sex: male; lifeStage: adult; occurrenceID: 2D62C800-7204-5833-BA28-076DDD92E064; Taxon: scientificName: Trilacuna nangunhe ; order: Araneae ; family: Oonopidae ; genus: Trilacuna ; Location: country: China; stateProvince: Yunnan; county: Lincang City; locality: Gengma County, Mengjian Village, Nantianmen ; verbatimElevation: 1955.18 m; verbatimCoordinates: 23°38′35.84″N, 99°23′6.96″E; Identification: identifiedBy: Yanfeng Tong; Event: samplingProtocol: sifting leaf litter; eventDate: 28/11/2024

Type status: Paratype. Occurrence: catalogNumber: SYNU-F-4865 -4869 ; recordedBy: Jimeng Ma; individualCount: 5; sex: 2 males, 3 females; lifeStage: adult; occurrenceID: A77A5695-8823-5FB1-81ED-00B694C26C07; Taxon: scientificName: Trilacuna nangunhe ; order: Araneae ; family: Oonopidae ; genus: Trilacuna ; Location: country: China; stateProvince: Yunnan; county: Lincang City; locality: Gengma County, Mengjian Village, Nantianmen ; verbatimElevation: 1955.18 m; verbatimCoordinates: 23°38′35.84″N, 99°23′6.96″E; Identification: identifiedBy: Yanfeng Tong; Event: samplingProtocol: sifting leaf litter; eventDate: 28/11/2024

Type status: Paratype. Occurrence: catalogNumber: SYNU-F-4870 ; recordedBy: Jimeng Ma; individualCount: 1; sex: female; lifeStage: adult; occurrenceID: A8C69DA3-FF04-56E8-9976-63DE19C19F14; Taxon: scientificName: Trilacuna nangunhe ; order: Araneae ; family: Oonopidae ; genus: Trilacuna ; Location: country: China; stateProvince: Yunnan; county: Lincang City; locality: Gengma County, Banmai Village, Back Mountain of the Management and Protection Station ; verbatimElevation: 1538.04 m; verbatimCoordinates: 23°26′24.93″N, 99°16′37.58″E; Identification: identifiedBy: Yanfeng Tong; Event: samplingProtocol: sifting leaf litter; eventDate: 27/11/2024

Description

Male ( Holotype). Body: habitus as in Fig. 4 A, C and E; body length 1.60; yellowish-brown. Carapace: 0.8 long, 0.63 wide; oval in dorsal view, sides smooth (Fig. 4 B and F). Eyes: Six eyes, well developed; ALE largest, PME smallest; ALE separated from edge of carapace by 1.25 diameters (Fig. 4 I). Mouthparts: chelicerae straight; labium rectangular, fused to sternum, anterior margin deeply incised; endites slender, distally branched (Fig. 4 D and G). Sternum: surface smooth, covered with many needle-like setae, medial area strongly rugose, posterior area strongly elevated, with several rows of ridges (Fig. 4 D and F). Abdomen: 0.94 long, 0.6 wide; elongated oval in dorsal view, covered with fine setae; booklung covers ovoid; sperm pore situated at level of anterior spiracles; posterior spiracles not connected by groove (Fig. 4 H). Palp: yellow; 0.54 long (0.18, 0.11, 0.10, 0.15); femur swollen (width / length = 0.67); tibia about as long as patella; bulb kidney-shape, base strongly swollen ventrally, tapering apically; psembolus complex, with basal leaf-shaped projection (blp), 1 needle-like branch (nlb), 1 blade-like lobe (bll), broad median branch (mb) and lateral branch (lb), surrounded by numerous fiber structures (Fig. 5 A – K).

Female ( paratype, SYNU-F-4865 ). Same as male, slightly larger than male, except as noted. Habitus as in Fig. 6 A, C and E. Body: 1.79 long. Carapace: 0.79 long, 0.66 wide. Sternum: without rows of ridges in posterior area (Fig. 6 D). Abdomen: 1.08 long, 0.65 wide. Epigastric area: with recurved, strongly sclerotised arches (sar) anterior to the spiracles (Fig. 6 G and Fig. 7 c ). Endogyne: with narrow, transversally elongated sclerite (tsc); with anterior T-shaped sclerite (as) and posterior small globular structure (glo); transverse bars (tba) with pair of short lateral apodemes (ap) (Fig. 7 d ).

Diagnosis

The new species is similar to T. jimengi sp. nov. in the smooth carapace and the rows of ridges on central area of sternum, but can be distinguished by the male epigastric region lacking a small spot (vs. with a spot; cf. Fig. 4 H and Fig. 1 H), the psembolus with needle-like branch and blade-like lobe (vs. absent; cf. Fig. 5 I and Fig. 1 I), the bulb lacking a subapical apophysis (vs. with a small one; cf. Fig. 5 D, E and Fig. 1 A, E) and the middle part of anterior margin of postgastric scutum being smooth (vs. triangular; cf. Fig. 7 c and Fig. 7 a ).

Etymology

The specific name is a noun in apposition taken from the type locality.

Distribution

Known only from the type locality, Yunnan Province, China (Fig. 8 ).

Figures

Figure 1. Trilacuna jimengi sp. nov., male holotype. A habitus, dorsal view; B prosoma, dorsal view; C habitus, ventral view; D prosoma, ventral view; E habitus, lateral view; F prosoma, lateral view; G labium and endites, ventral view; H abdomen, ventral view; I prosoma, anterior view. Abbreviations: slh = small hole; sri = small ridges. Scale bars: A – F, I = 0.4 mm; G, H = 0.2 mm.

Figure 4. Trilacuna nangunhe sp. nov., male holotype. A habitus, dorsal view; B prosoma, dorsal view; C habitus, ventral view; D prosoma, ventral view; E habitus, lateral view; F prosoma, lateral view; G labium and endites, ventral view; H abdomen, ventral view; I prosoma, anterior view. Abbreviation: sri = small ridges. Scale bars: A – F, I = 0.4 mm; G, H = 0.2 mm.

Figure 5. Trilacuna nangunhe sp. nov., male holotype, light (A – C) and SEM (D – K) images. A left palp, prolateral view; B left palp, dorsal view; C left palp, retrolateral view; D left palp, prolateral view; E left palp, dorsal view; F left palp, retrolateral view; G bulb, prolateral view; H bulb, retrolateral view; I distal part of bulb, prolateral view; J distal part of bulb, dorsal view; K distal part of bulb, retrolateral view. Abbreviations: bll = blade-like lobe; blp = basal leaf-shaped projection; lb = lateral branch; mb = medial branch; nlb = needle-like branch. Scale bars: A – H = 0.1 mm; I – K = 0.05 mm.

Figure 6. Trilacuna nangunhe sp. nov., female paratype. A habitus, dorsal view; B prosoma, dorsal view; C habitus, ventral view; D prosoma, ventral view; E habitus, lateral view; F prosoma, lateral view; G abdomen, ventral view; H prosoma, anterior view. Scale bar: 0.4 mm.

Figure 8. Distribution records of two new species from Nangunhe Nature Reserve, Yunnan, China. 1. T. jimengi sp. nov.; 2. T. nangunhe sp. nov.

Figure 7 c. Trilacuna nangunhe sp. nov., ventral view;

Figure 7 d. Trilacuna nangunhe sp. nov., dorsal view.

Figure 7 a. Trilacuna jimengi sp. nov., ventral view;