Ischnothyreus qiuxing Tong & Li, 2020

Tong, Yanfeng, Li, Shuqiang & Bian, Dongju, 2020, Taxonomic study of the genus Ischnothyreus Simon, 1893 from Myanmar (Araneae, Oonopidae), ZooKeys 993, pp. 1-26 : 1

Ischnothyreus qiuxing Tong & Li sp. nov. Figures 7 , 16E, F

Type material.

Holotype ♀: Myanmar, Kachin State, Putao, Around Ziradum Village; 27°33'465"N, 97°06'580"E; elevation ca 1051 m; 8.V.2017; Wu J. & Chen Z. leg. (IZCAS AR-25176).

Diagnosis.

The new species is similar to I. balu Kranz-Baltensperger, 2011 in the circular atrium, but can be distinguished by the size of atrium (nearly 1/5 the length of postgastric scutum (Fig. 16E ) vs more than 1/3 the length of postgastric scutum; Kranz-Baltensperger 2011: fig. 2F, H) and the greater sinuosity of the winding tube (Fig. 16F ) (vs short, simple winding tube; Kranz-Baltensperger 2011: fig. 2G).

Description.

Female (holotype). Body: habitus as in Fig. 7A-C ; body length 2.01. Carapace: 0.87 long, 0.72 wide; yellow, without any pattern, ovoid in dorsal view, strongly elevated in lateral view, surface finely reticulate, fovea absent, lateral margin straight, smooth (Fig. 7D, F ). Clypeus: height about equal to ALE radius or less (Fig. 7G ). Eyes: six, in one group, well developed, subequal, ALE circular, PME and PLE oval, posterior eye row recurved from above, procurved from front (Fig. 7D, G ). Sternum: as long as wide, yellow, uniform, not fused to carapace, surface smooth, setae sparse (Fig. 7E ). Mouthparts: chelicerae, endites and labium orange; chelicerae straight, base of fangs unmodified (Fig. 7G ); labium rectangular, not fused to sternum, anterior margin not indented at middle; endites unmodified (Fig. 7E ). Abdomen: 1.35 long, 0.92 wide; dorsal scutum weakly sclerotized, very small, not fused to epigastric scutum; epigastric and postgastric scutum well sclerotized, pale orange, unfused (Fig. 7A, B ). Legs: pale orange, femur I with two prolateral spines, tibia I with four pairs, metatarsus I with two pairs of long ventral spines. Leg II spination is similar to leg I except femur with only one prolateral spine. Legs III and IV spineless. Epigastric area: surface without external features (Fig. 7H ). Endogyne: from the middle of the slightly thickened margin of the postgastric scutum runs a dark, very simple winding tube posteriorly, ending in a circular atrium (Fig. 16E, F ).

Male. Unknown.

Etymology.

The specific name is derived from Chinese pinyin, “qiuxing”, which means “circular”, referring to the circular atrium; noun in apposition.

Distribution.

Known only from the type locality.

Figures

Figure 7. Ischnothyreus qiuxing sp. nov., female holotype A-C habitus, dorsal, ventral and lateral views D-G prosoma, dorsal, ventral, lateral and anterior views H epigastric region, ventral view. Scale bars: 0.4 mm (A-C); 0.2 mm (D-H).

Figure 16. Ischnothyreus spp., female copulatory organ A, B I. hponkanrazi sp. nov. C, D I. meukyawwa sp. nov. E, F I. qiuxing sp. nov. G, H I. taunggyi sp. nov. A, C, E, G ventral view B, D, F, H dorsal view. Abbreviations: a = apodemes; ass = anchor-shaped structure; bsa = bell-shaped atrium; csa = circular atrium; nsa = nipple-shaped atrium; oa = opening of the atrium; wt = winding tube. Scale bars: 0.2 mm.