Figs 1C–D, 5–6, 10A
Type material. MYANMAR: Kachin State: Holotype: male (IZCAS-Ar42320Fo), Late Cretaceous amber from Hukawng Valley. No biotic syninclusions.
Material studied for comparison. Furcembolus cf. crassitibia (Fig. 10B, SEABRI-Ar002), Late Cretaceous amber from Hukawng Valley. No biotic syninclusions.
Etymology. The specific name is a patronym in honour of the late Chinese arachnologist Fengzhen Wang (1906–1978) and is a noun (name) in genitive case.
Diagnosis. This species resembles Furcembolus andersoni (see Wunderlich 2008: 582, figs 20–22, photos 75–76) by possessing a long apophysis on embolus, but can be distinguished by the presence of apophysis on the tibia, tibia swollen, the angle of embolus and the sclerotized apophysis of embolus (Figs 5, 10A). In F. andersoni, the tibia is without apophysis. The embolus of F. crassitibia (see Wunderlich 2017: 129, fig. 78) is similar to F. fengzheni spec. nov., but can be distinguished by the angle of embolus. The embolus of F. crassitibia bend twice in a right angle. The embolus of F. fengzheni spec. nov. slightly bending (Figs 5, 10A).
Description. Male (holotype): Total length 3.12, carapace 1.43 long, opisthosoma 1.69 long, 1.14 wide. Left palp not visible, left leg I: 8.46 (2.45 + 0.38 + 2.69 + 2.22 + 0.72), leg II: 5.20 (1.53 + 0.30 + 1.48 + 1.33 + 0.56), leg III: 3.40 (0.88 + 0.31+ 0.91 + 0.85 + 0.45), leg IV: – (1.32 + – + – + – + –); right palp: 1.23 (0.61 + 0.16 + 0.46), right leg I: 8.29 (2.08 + 0.44 + 2.81 + 2.28 +0.68), leg II: 5.20 (1.36 + 0.37 + 1.55 + 1.36 + 0.56), leg III absent, leg IV: 5.32 (1.42 + 0.36+ 1.42 + 1.51 + 0.61). Eyes: diameter ALE 0.06, AME not visible, diameter PLE 0.06. Habitus as in Figs 6D–E. Colour in amber: prosoma and opisthosoma yellow-brown, legs light yellow. Prosoma (Figs 6A, D–E): carapace (Fig. 6A) finely granulated, margin distinctly serrated, cephalic part of carapace clearly highest in its posterior portion; six eyes almost ovoid, AME> PLE = ALE; clypeus vertical anteriorly, without modifications, 0.31 high; chelicerae without modifiactions; labium triangular, distally obtuse; sternum rough. Leg slender, serrate setae present on metatarsal and tarsal, serration more apparent in tarsal; elongated trichobothria on femur, tibia and metatarsal. Opisthosoma (Figs 6B, D–E): oval with 4 or 5 sclerotized lateral plates, smooth, modified by tiny pits, covered with thin setae; ventral scutum rugose. Lateral scutum I reaches the half of margin of pulmonary plate. Spinnerets not visible. Palp (Figs 5, 10A): femur approximately 4 times longer than patella; patella short; tibia swollen, approximately 3 times as wide as femur, with apophysis on the distal; cymbium small and compressed; bulb long, slightly swollen; embolus originates from the apex of oval palpal bulb, bending inwards in the middle; embolus with a sclerotized apophysis.