Trilacuna jimengi 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 jimengi Dai & Tong sp. nov.

Materials

Type status: Holotype. Occurrence: catalogNumber: SYNU-F- 4861 ; recordedBy: Jimeng Ma; individualCount: 1; sex: male; lifeStage: adult; occurrenceID: 9AB5A0E1-2740-5342-96DB-8FAB109DF0BF; Taxon: scientificName: Trilacuna jimengi ; order: Araneae ; family: Oonopidae ; genus: Trilacuna ; Location: country: China; stateProvince: Yunnan; county: Lincang City; locality: Cangyuan Wa Autonomus County, 500 m Northeast of Erma River ; verbatimElevation: 1561.05 m; verbatimCoordinates: 23 ° 12 ′ 44 ″ N, 99 ° 11 ′ 58 ″ E; Identification: identifiedBy: Yanfeng Tong; Event: samplingProtocol: sifting leaf litter; eventDate: 30 / 09 / 2024

Type status: Paratype. Occurrence: catalogNumber: SYNU-F- 4862-4863 ; recordedBy: Jimeng Ma; individualCount: 2; sex: female; lifeStage: adult; occurrenceID: 5DFCD329-533F-5A50-A5BA-09A7C7D79AAB; Taxon: scientificName: Trilacuna jimengi ; order: Araneae ; family: Oonopidae ; genus: Trilacuna ; Location: country: China; stateProvince: Yunnan; county: Lincang City; locality: Cangyuan Wa Autonomus County, 500 m Northeast of Erma River ; verbatimElevation: 1561.05 m; verbatimCoordinates: 23 ° 12 ′ 44 ″ N, 99 ° 11 ′ 58 ″ E; Identification: identifiedBy: Yanfeng Tong; Event: samplingProtocol: sifting leaf litter; eventDate: 30 / 09 / 2024

Description

Male ( Holotype). Body: habitus as in Fig. 1 A, C and E; body length 1.58; yellow. Carapace: 0.78 long, 0.64 wide; oval in dorsal view, sides smooth (Fig. 1 B and F). Eyes: Six eyes, well developed; ALE separated from edge of carapace by 1.1 diameters (Fig. 1 I). Mouthparts: chelicerae straight; labium rectangular, fused to sternum, anterior margin deeply incised; endites slender, distally only slightly branched (Fig. 1 D and G). Sternum: surface smooth, sternum covered with many needle-like setae, with several rows of ridges and short and fine setae in median part (Fig. 1 D). Abdomen: 0.92 long, 0.61 wide; elongated oval in dorsal view, covered with fine setae; booklung covers ovoid (Fig. 1 H); sperm pore situated in front of anterior spiracles; posterior spiracles connected by shallow groove; with small hole situated between anterior and posterior spiracles. Palp: yellow; 0.51 long (0.16, 0.11, 0.10, 0.14); femur swollen (width / length = 0.75); tibia about as long as patella; bulb kidney-shape, tapering apically, with a small apophysis on subapical region; psembolus complex, with basal leaf-shaped projection (blp), broad median branch (mb) and lateral branch (lb), surrounded by numerous fibre structures (Fig. 2 A – K).

Female ( paratype, SYNU-F- 4862). Same as male, except as noted. Habitus as in Fig. 3 A, C and E. Body: 1.55 long. Carapace: 0.69 long, 0.58 wide. Sternum: without rows of ridges in median part (Fig. 3 D). Abdomen: 1.87 long, 0.59 wide. Epigastric area: middle part of anterior margin of postgastric scutum triangular shape; with recurved, strongly sclerotised arches (sar) anterior to the spiracles (Fig. 3 G and Fig. 7 a ). Endogyne: with narrow, transversally elongated sclerite (tsc); with anterior T-shaped sclerite (as) and posterior large ellipsoidal globular structure (glo); transverse bars (tba) with pair of short lateral apodemes (ap) (Fig. 7 b ).

Diagnosis

The new species is similar to T. wuhe Tong, Zhang & Li, 2019 in the rows of ridges on central area of sternum, but can be distinguished by the smooth carapace (vs. granulate; cf. Fig. 1 B, F, Fig. 3 B, F and Tong et al. (2019): figs. 16 D, F, 18 D and F), the small apophysis on subapical region of bulb (vs. absent; cf. Fig. 2 A, E and Tong et al. (2019): figs. 17 A and C) and by the large ellipsoidal globular structure of endogyne (vs. small; cf. Fig. 7 a , b and Tong et al. (2019): fig. 25 B).

Etymology

The specific name is named after the collector, Jimeng Ma.

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 2. Trilacuna jimengi sp. nov., male holotype, light (A-C) and SEM (D-K) images. A left palp, prolateral view; B left palp, dorsal view, arrows in A, B and E show the small apophysis; 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: blp = basal leaf-shaped projection; lb = lateral branch; mb = medial branch. Scale bars: A – H = 0.1 mm; I – K = 0.05 mm.

Figure 3. Trilacuna jimengi 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 bars: A – F, H = 0.4 mm; G = 0.2 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 a. Trilacuna jimengi sp. nov., ventral view;

Figure 7 b. Trilacuna jimengi sp. nov., dorsal view;