Class: Araneae Clerck, 1757.
Family: Nephilidae Simon, 1894.
Genus: Nephila Leach, 1815.
Species: Nephila jurassica sp. nov.
Derivation of name: From Jurassic, the age of the fossil.
Diagnosis: Nephila with setal tufts (gaiters) in distal half of tibia 3 (in addition to tibiae 1, 2 and 4); opisthosoma ovoid, widest in anterior half, tapering posteriorly; epigyne nose shaped.
Holotype: CNU-ARA-NN2010008, College of Life Sciences, Capital Normal University, Beijing. No other specimens known.
Description: Adult female. Specimen preserved dorsal-down in matrix so that left legs (in life) on right side of specimen (a,b). Ventral structures displaced to left relative to carapace, only edge of which is visible, but outline can be determined; longer than wide: length 9.31, width 6.83 (ratio 1.36); subrectangular, slightly bowed laterally, with anterior median projection, smooth lateral margins (no denticles); fovea shallow, recurved, with pair of recurved triangular grooves immediately posterior (forming an inverted W), 5.10 from anterior margin (i.e. slightly posterior to midpoint); carapace cuticle smooth with fine setae; eyes not visible. Sternum subtriangular, widest at anterior margin, not projecting between leg 4 coxae. Labium about as long as wide. Chelicerae revealed in low-angle light, superimposed on anterior part of carapace; short, stout, paturon directed ventrally in life (not correct), with curved fang and cluster of triangular teeth on cheliceral furrow; length 3.27. Parts of pedipalps visible in front of carapace: patella length 1.55.
Figure 1. Nephila jurassica sp. nov. holotype (CNU-ARA-NN2010008). (a) Whole specimen, dry; (b) explanatory drawing to accompany (a); scale bar, 5 mm. Setal brushes and trichobothria diagrammatic. car, carapace; ch, chelicera; cx, coxa; ep, epigyne; f, fovea; fe, (more ...)
Walking leg formula (longest to shortest) 1243; femora, tibiae and metatarsi of leg 1, and to a lesser extent 2, greatly elongated. Podomere lengths: leg 1 trochanter 1.25, femur 14.57, patella 3.75, tibia 15.39, metatarsus 16.92, tarsus 4.62; leg 2 femur 11.42, patella 3.25, tibia 9.56, metatarsus 11.49, tarsus 3.21; leg 3 femur 6.89, patella 2.10, tibia 4.95, metatarsus 5.24, tarsus 2.29; leg 4 femur 9.83, patella 2.56, tibia greater than or equal to 5.39. Macrosetae and fine covering of setae on all podomeres; setae smooth, not plumose (d). Trichobothria visible as fine, relatively short hairs crossing setation at high angle, emerging from distinct bothria. Femora with short, stout macrosetae ventrally, becoming longer distally, arranged in three rows proximally, two distally (fewer on shorter femur 3); no trichobothria; setal brush distally. Patellae with single lateral macroseta; setal brush on most of podomere. Tibiae with cluster of relatively short trichobothria (not feathery) proximally (b,c); prominent setal brush in distal half; scattered macrosetae. Metatarsi with setal brush in distal half; scattered macrosetae, cluster of at least three macrosetae at distal joint. Tarsi without setal brush; few, small macrosetae.
Figure 2. Nephila jurassica sp. nov. holotype. (a) Epigyne, (b) basal part of right leg 3 tibia showing setae, macrosetae, setal brush (right) and cluster of basal trichobothria, (c) close-up of (b) showing trichobothria, (d) coarse setae on dorsal opisthosoma, (more ...)
Opisthosoma left and posterior margins broken, but true margins probably lay close to preserved edges; longer than wide (length 15.36, width 9.50; length/width ratio 1.62), subovate, greatest width in anterior half and tapering gently posteriorly (not parallel-sided), densely clothed in fine setae. Low-angle light reveals compact, human nose-shaped epigyne (a) in median position on epigastric furrow; width 1.50. Posterior to epigyne, ventral opisthosomal cuticle fragmentary to absent, revealing coarser setation of dorsal surface (d), but patches of finer setae of ventral surface crossing coarser setae of dorsal surface represent spinnerets in subterminal position on opisthosoma (e).