Sinamma quadrata Cheng & Ren & Tong & Bian & Li 2022, sp. nov.
Creators: name: Cheng, Weihua
name: Ren, Lingshu
name: Tong, Yanfeng
name: Bian, Dongju
name: Li, Shuqiang
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Tetrablemmidae
Sinamma
Sinamma quadrata

description: Sinamma quadrata Tong & Li, sp. nov.
Figs 1A–I, 2A–I, 3A, B, 4A–C, 8
Type material. Holotype: Male (SYNU-497), near Donghua Temple (24º9'15.48"N, 113º26'36.6"E; elevation 157 m), Yingde City, Qingyuan City, Guangdong Province, China, 5 April 2021, W. Cheng, Y. Huang, K. Yang and T. Jiang leg. Paratypes: 3 males (SYNU-498-500) and 5 females (SYNU-501-505), same data as holotype.
Etymology. The specific name is an adjective and derives from the Latin word “quadratus”, referring to the quadrangular shape of the palpal bulb.
Diagnosis. Males of Sinamma quadrata sp. nov. resemble Sinamma oxycera Lin & Li, 2014 in having the conical cheliceral horn, the pointed eye tubercles and the strongly modified leg I. Females of the new species resemble Sinamma oxycera by the finger-shaped inner vulval plate. Males of Sinamma quadrata sp. nov. can be distinguished from Sinamma oxycera and S. yingae sp. nov. by the quadrangular shaped palpal bulb and the beltshaped embolus (Fig. 2A, B) (vs pyriform-shaped palpal bulb and thread-like embolus in S. oxycera and S. yingae (Lin & Li 2014: fig. 2A, B; Fig. 6A, B)). Males of the new species also can be distinguished from S. yingae by having pointed eye tubercles (Fig. 1G, H) (vs lacking pointed eye tubercles in S. yingae (Fig. 5G, H)). Females of the new species can be distinguished from S. oxycera Lin & Li, 2014 by lacking cephalic tubercles (Fig. 1F, I) (vs with a pair of cephalic tubercles in S. oxycera (Lin & Li 2014: fig. 1F, H)); from S. yingae sp. nov. by having fingershaped inner vulval plate (Fig. 4C), the posterior part of sternum strongly bulged (Fig. 1E, F) and the cephalic part slightly elevated (Fig. 1F) (vs triangle-shaped inner vulval plate (Fig. 7C), flat posterior part of the sternum (Fig. 5E, F), and cephalic part slightly sloping, with the highest point of carapace at ocular area (Fig. 5F) in S. yingae).
Description. Male (holotype, SYNU-497). Coloration: body reddish-brown; legs yellowish brown. Measurements: total length 1.31; carapace 0.70 long, 0.57 wide, 0.43 high; abdomen 1.00 long, 0.73 wide, 0.62 high; clypeus 0.39 high; sternum 0.39 long, 0.41 wide. Length of legs: I 1.64 (0.55, 0.20, 0.36, 0.26, 0.27); II 1.51 (0.50, 0.19, 0.35, 0.25, 0.22); III 1.36 (0.41, 0.19, 0.33, 0.20, 0.23); IV 1.80 (0.55, 0.19, 0.45, 0.34, 0.27).
Carapace (Fig. 1A, C, G, H): reticulated, strongly rugose, margin with small denticles; ocular area raised, eye tubercle long, sharp (Fig. 1G, H); clypeus very high, anterior margin rounded (Fig. 1G, H); cheliceral horn long, basally wide, distally crooked (Fig. 1H); sternum with sparse setae, rugose (Fig. 1B). Legs (Fig. 3A, B): femur I swollen; tibiae I–III with 3 trichobothria, tibia IV with 4 trichobothria, and metatarsi I-IV with a trichobothrium; tibia I with one very small ventral tubercle (svt); metatarsus I with two distal tubercles (dt).
Abdomen (Fig. 1B, C): booklung covers long oval, dark brown; dorsal scutum oval, finely reticulated; ventral scutum rugose; postgenital plate narrow, subequal in width to preanal plate (Fig. 1B).
Palp (Fig. 2A–I): femur smooth; patella approximately 1/2 femur in length, connected to tibia subbasally; bulb long, quadrangular; embolus long, belt-shaped, curved slightly, strongly sclerotized; sperm duct extending, visible through the bulbal integument.
Female (paratype, SYNU-501). Coloration: same as in male.
Measurements: total length 1.49; carapace 0.67 long, 0.53 wide, 0.33 high; abdomen 1.15 long, 0.81 wide, 0.70 high; clypeus 0.22 high; sternum 0.39 long, 0.40 wide. Length of legs: I 1.62 (0.55, 0.18, 0.37, 0.25, 0.27); II 1.51 (0.47, 0.18, 0.34, 0.25, 0.27); III 1.36 (0.39, 0.17, 0.31, 0.24, 0.25); IV 1.79 (0.54, 0.18, 0.46, 0.34, 0.27).
Carapace (Fig. 1D, F, I): cephalic part slightly elevated (Fig. 1F), clypeus lower than in male; cheliceral horn absent. Posterior part of sternum strongly bulged (Fig. 1F). Legs as in male, except for leg I undecorated.
Abdomen (Fig. 1E, F): ventral episgastric scutum rugose; postgenital plate straight, as wide as preanal plate; preanal plate rectangular-shape.
Genitalia (Fig. 4A–C): epigynal fold wide (Fig. 4A); vulval stem wide, strongly sclerotized; lateral horns slightly sclerotized, supporting the base of vulval ducts of spermathecae; inner vulval plate finger-shaped, slightly sclerotized (Fig. 4C).
Distribution. Known only from the type locality (Fig. 8).
description: Published as part of Cheng, Weihua, Ren, Lingshu, Tong, Yanfeng, Bian, Dongju & Li, Shuqiang, 2022, Two new species of the spider genus Sinamma Lin & Li, 2014 (Araneae, Tetrablemmidae) from Guangdong Province, China, pp. 443-454 in Zootaxa 5091 (3) on pages 444-448, DOI: 10.11646/zootaxa.5091.3.4, http://zenodo.org/record/5848301