Septsigilla Zhang & Zhang, 2025

Zhang, Haibin, Yu, Kun, Zuo, Anru & Zhang, Feng, 2025, Description of a new genus, Septsigilla gen. nov., with two new species from China (Araneae: Miturgidae: Systariinae), Zootaxa 5666 (1), pp. 125-135 : 126-127

Genus Septsigilla Zhang & Zhang gen. nov. (七sea)

Type species. Septsigilla tongbiguan Zhang & Zhang sp. nov.

Etymology. The generic name is a combination derived from the Latin “ septem ” (seven) and “ sigilla ”, referring to the seven sigilla on the sternum of the species described herein. The gender is neutral.

Diagnosis. This new genus shares similarities with other genera of Systariinae in possessing a compact eye group, separated ALS, relatively longer leg III (not less than 90% of the length of leg II), notched trochanters, the presence of a cymbial groove and the absence of a cymbial spur on the male cymbium, as well as posteriorly positioned spermathecae and anteriorly positioned bursae on the female epigyne, but can be distinguished from the other genera in this subfamily (except for Tamin ) by having the smallest anterior median eyes. The male can be distinguished from Tamin by the posteriorly elongated tegulum which extends to the median part of the tibia, and the whiplike embolus ( Figs 3A–C , 6A–C ; vs. the non-elongated tegulum and triangular embolus in Tamin , see Deeleman-Reinhold 2001: 213, fig. 250). The female differs from Tamin in that the bursae are almost as large as the primary spermathecae, and the connecting tubes are sac-like ( Figs 3E , 6E , vs. the bursae significantly larger than the primary spermathecae and the connecting tubes being narrow and tubular in Tamin , see Deeleman-Reinhold 2001: figs 243, 256).

Description. Medium-sized spiders (5.38–6.56 mm), prosoma yellowish brown, with black radial patterns; radial and cervical grooves indistinct; fovea reddish-brown, longitudinal, presenting at posterior part of thoracic region ( Figs 1A, C , 4A, C ). Ocular area narrow and dark, ca. 0.6 times width of CRW; AME smallest, median eyes circular, lateral eyes oval-shaped, all eyes with black rings, anterior eye row slightly recurved, posterior eye row almost straight in dorsal view ( Figs 2A–B , 5A–B ). Chelicera yellowish brown, with three promarginal teeth and two or three retromarginal teeth. Endite longer than wide, without fold or impression ( Figs 1B, D , 4B, D ). Sternum shield-shaped, longer than wide, with seven sigilla, paired sigilla with nearby slit sensilla ( Figs 1B , 2C , 4B , 5C ). Legs pale yellow, leg formula 4123. Leg III about 0.9 times the length of Leg II. Coxa Ⅰ with retrocoxal window (RCW, Fig. 7 ), metatarsi III and IV with conspicuous preening brushes, tibiae III and IV, metatarsi III and IV each with three pairs of robust ventral spines. Leg tarsi with relatively degenerated claw tufts ( Fig.7 ).

Opisthosoma oval, dorsally brownish yellow to gray, with two pairs of muscular impressions ( Figs 1A, C , 4A, C ). ALS spacing about half their diameter, tapering distally; PMS slender and short; PLS with two segments, basal segment cylindrical and similar in length to ALS, distal segment conical, shorter than half length of basal segment ( Figs 2D–E , 5D–E ).

Male Palp. Tibia length and width nearly equal, ventral side with one small basal apophysis. RTA slender, with rectangular extension at base in ventral view, curved to ventral side in retrolateral view. Cymbium with basal concavity on retrolateral side. The posterior elongation of tegulum extending to median part of tibia. Sperm duct running along distal and retrolateral margins of tegulum. Embolic base spherical, half of base membranous. Conductor membranous, originating from distal part of tegulum, edges rolling upward ( Figs 3A–C , 6A–C , 8 ).

Epigyne. Epigynal plate slightly sclerotized. Atrium triangular, posteriorly positioned, carrying sclerotized anterior margin. Copulatory opening locating below sclerotized anterior margin of atrium, not visible in ventral view ( Figs 3D , 6D ). Primary spermatheca and secondary spermatheca heavily sclerotized, connected to each other. Copulatory duct short and thick. Bursa slightly sclerotized, approximately oval-shaped. Connecting tube flat and sac-like ( Figs 3E , 6E ).

Composition. Septsigilla tongbiguan Zhang & Zhang sp. nov.; S. zhongi Zhang & Zhang sp. nov.

Distribution. China (Xizang, Yunnan).

Figures

FIGURE 1. Septsigilla tongbiguan Zhang & Zhang sp. nov., male holotype (A–B) and female paratype (C–D). Habitus, in dorsal (A, C) and ventral (B, D) view. Scale bars = 2 mm.

FIGURE 2. Septsigilla tongbiguan Zhang & Zhang sp. nov., male holotype (A–D). A. Prosoma, frontal view; B. Eye region, dorsal view; C. Sternum. D. Male spinnerets, ventral view; E. Female spinnerets, ventral view. Abbreviations: si, sigillum; ss, slit sensilla.

FIGURE 3. Septsigilla tongbiguan Zhang & Zhang sp. nov., male holotype left palp (A–C) and female paratype epigyne (D–E), in prolateral (A), ventral (B, D), retrolateral (C) view and dorsal (E) view.Abbreviations: B, bursa; C, conductor; CD, copulatory duct; CO, copulatory opening; CT, connecting tube; E, embolus; FD, fertilization duct; PS, primary spermatheca; RTA, retrolateral tibial apophysis; SD, sperm duct; SS, secondary spermatheca; T, tegulum; vBTA, ventral basal tibial apophysis.

FIGURE 4. Septsigilla zhongi Zhang & Zhang sp. nov., male holotype (A–B) and female paratype (C–D). Habitus, in dorsal (A, C) and ventral (B, D) view. Scale bars = 2 mm.

FIGURE 5. Septsigilla zhongi Zhang & Zhang sp. nov., Male holotype (A–D). A. Prosoma, frontal view; B. Eye region, dorsal view; C. Sternum. D. Male spinnerets, ventral view; E. Female spinnerets, ventral view. Abbreviations: si, sigillum; ss, slit sensilla.

FIGURE 6. Septsigilla zhongi Zhang & Zhang sp. nov., male holotype left palp (A–C) and female paratype epigyne (D–E), in prolateral (A), ventral (B, D), retrolateral (C) view and dorsal (E) view. Abbreviations: B, bursa; C, conductor; CD, copulatory duct; CO, copulatory opening; CT, connecting tube; DPA, dorsal patellar apophysis; E, embolus; ET, embolar tooth; FD, fertilization duct; PS, primary spermatheca; RTA, retrolateral tibial apophysis; SD, sperm duct; SS, secondary spermatheca; T, Tegulum; vBTA, ventral basal tibial apophysis.

FIGURE 7. Right leg Ⅰ of male paratype of Septsigilla tongbiguan Zhang & Zhang sp. nov. (A) and Septsigilla zhongi Zhang & Zhang sp. nov. (B) in retrolateral view. Abbreviations: RCW, retrocoxal window.

FIGURE 8. Conductor and embolus of Septsigilla tongbiguan Zhang & Zhang sp. nov. (A) and Septsigilla zhongi Zhang & Zhang sp. nov. (B). Abbreviations: ET, embolar tooth.