Furcembolus chuandiani Jiang & Li, 2021

Xin, Yafei, Jiang, Tongyao, Yao, Zhiyuan & Li, Shuqiang, 2021, Three new species of the extinct spider genus Furcembolus (Araneae: Pacullidae) from Late Cretaceous Burmese amber, Zootaxa 4984 (1), pp. 258-273 : 260-261

Furcembolus chuandiani Jiang & Li spec. nov.

Figs 1A–B , 3–4 , 9B

Type material. MYANMAR: Kachin State: Holotype: male (IZCAS-Ar42319Fo), Late Cretaceous amber from Hukawng Valley . Syninclusion includes a Coleoptera larvae behind the opisthosoma of the spider.

Material studied for comparison. Furcembolus cf. equester ( Fig. 9A , SEABRI-Ar001), Late Cretaceous amber from Hukawng Valley. No biotic syninclusions .

Etymology. The specific name is a patronym in honour of the late Chinese arachnologist Chuandian Zhu (1925–2003) and is a noun (name) in genitive case.

Diagnosis. This species resembles Furcembolus equester (see Wunderlich 2015: 163, figs 111–112, photos 48–49) by the absence of apophysis on the embolus, but can be distinguished by the twisted tip of the embolus ( Figs 3 , 9B ), while the tip of embolus is sharp and straight in F. equester ( Fig. 9A ).

Description. Male (holotype): Total length 3.87, carapace 1.74 long, 0.96 wide, opisthosoma 2.13 long. Left palp: 1.05 (0.57 + 0.16 + 0.32), left leg I: 10.12 (2.59 + 0.18 + 3.72 + 2.81 + 0.82), leg II-IV absent; right palp: 1.04 (0.49 + 0.13 + 0.42), right leg I: - (2.94 + 0.43 + 2.15 + 2.84 + –), leg II:6.32 (2.03 + 0.47 + 1.21 + 1.88 + 0.73), leg III: – (1.45 + – + 1.36 + 1.37 + 0.56), leg IV: 6.29 (1.62 + 0.53 + 1.78 + 1.83 + 0.53). Eyes: diameter ALE 0.16, diameter AME 0.11, diameter PLE 0.12, distance AME-AME 0.07. Habitus as in Figs 4D–E . Colour in amber: body and legs dark brown. Prosoma ( Figs 4A–E ): carapace ( Fig. 4A ) finely granulated, margin distinctly serrated, cephalic part of carapace clearly highest in its posterior portion; six eyes ( Fig. 4B ) almost ovoid, ALE> PLE> AME; clypeus vertical anteriorly; chelicerae ( Fig. 4C ) with two tiny teeth, unmodified; labium triangular, distally obtuse; sternum rough. Leg with distinctly serrate setae, elongated trichobothria on femur, tibia and metatarsal. Opisthosoma ( Figs 4D–E ): oval with sclerotized lateral plates, smooth, modified by tiny pits, covered with thin setae; ventral scutum rugose. Spinnerets not visible. Palp ( Figs 3A–D , 9B ): femur more 3 times longer than patella; patella short; tibia slightly swollen, approximately twice as wide as femur, without apophysis; cymbium small and compressed; bulb long, proximal slightly swollen; embolus originates from the apex of oval palpal bulb; the tips of embolus ( Figs 3A, B , 9B ) twisted, tiny, bent; embolus without apophysis.

Figures

FIGURES 1A–D. Ambers pieces containing Furcembolus chuandiani spec. nov., holotype male (A–B) and Furcembolus fengzheni spec. nov., holotype male (C–D) (A, C dorsal; B, D ventral). Scale bars: 10.0 mm.

FIGURES 3A–D. Furcembolus chuandiani spec. nov., holotype male. A–B Right embolus, arrow points at tip of embolus (A dorsal, B retrolateral). C Right palp, retrolateral. D Left palp, retrolateral. Scale bars: A: 0.20 mm, B: 0.10 mm, C–D: 0.50 mm. B—bulb, Cy—cymbium, E—embolus, Fe—femur, Pa—patella, Ti—tibia.

FIGURES 4A–E. Furcembolus chuandiani spec. nov., holotype male.A Carapace, lateral. B Ocular area, dorsal. C Chelicerae, frontal. D–E Habitus, lateral. Scale bars: A, D–E: 1.00 mm; B: 0.20 mm; C: 0.50 mm. ALE—anterior lateral eye, AME—anterior median eye, Fg—fangs, PLE—posterior lateral eye.

FIGURES 9A–B. †Furcembolus spp., male palp. A Furcembolus cf. equester (SEABRI-Ar001), left palp, retrolateral. B Furcembolus chuandiani spec. nov. (IZCAS-Ar42319Fo), right palp, retrolateral, horizontally flipped. Scale bars: 0.20 mm.