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Nuctenea umbratica  (Clerck, 1757) (Walnut orb-weaver)
≤ 1900   1901-1979   1980-2005   2006 ≤
Description: Carapace brown with two dark parallel lines from fovea to posterior medial eyes. Sternum, coxae and trochanters dark brown or blackish and furnished with long white hairs. Abdomen flattened dorsoventrally, widest at middle. Anterior edge of abdomen idented in middle in some specimens. Folium dark brown sometimes outlined with narrow, wavy light bands and lighter sides. Some specimens appear lighter due to dense hairing with lighter hairs which may be further exaggerated by reflections artefacts on flash photos. Venter black with a white or yellow comma-shaped mark in each side, the marks being more curved than those of N. silvicultrix. Legs brown or dark brown with darker annulations. Legs may also appear annulated due to rings of dense white hairs. Epigynal scape short and horseshoe-shaped. Biology: The species spends t Size: Female 9-14 mm; male 7-9 mm.

Genus: Nuctenea Simon, 1864. Characters of genus: Carapace rather broad and flattened. Anterior medial eyes are situated on a low elevation. Medial trapezium slightly wider at rear. Height of clypeus about one diameter of an anterior medial eye. Lower edge of clypeus curve downward in area below anterior medial eyes. Abdomen flattened with a wide dark folium extending full length of abdomen. Several light spots are present within folium as are four pairs of large, brown or blackish impressed dots (sigilla). Venter black with a white or yellow comma-shaped mark in each side. Males with a hook on distal margin of coxa I opposite a depression on femur II (Almquist 2005).

Family: Araneidae Simon, 1895 (Typical Orb Weavers). Characters of family: The araneids belong to the group of ecribellate spider families having 8 eyes and 3 tarsal claws. The eyes are arranged in 2 rows of 4 with the lateral eyes widely separated from the medial eyes. The carapace is often flat with a distinct head region. The chelicers are strong having a lateral condyle (boss at base of chelicer). Labium is wider than long and rebordered (swollen at anterior edge). Maxilla (basal part of palp used for chewing prey) are widest anteriorly. Legs with 3 claws and often furnished with strong spines and trichobothria on all segments except tarsi. Often legs are clearly annulated. The abdomen is usually globose and nearly always with species-specific often bright colour patterns. The abdomens of some species are round-shouldered while others have humps, the latter species often referred to as angulate orb weavers. Some tropical species have large outgrows on the abdomen. A colulus (midline appendage or tubercle) is present in front of the anterior spinnerets. The tracheal spiracle is situated close to spinnerets. Araneids belong to the entelegyne group of spiders often having large and complex epigynes sometimes with a large flexible scapus (finger-, tongue-, or lip-like projection arising in the midline of the epigyne). The male palp is complex.
Female
Female
Juvenile
Male
Male
Female
Female abdominal markings
Female
Female, venter
Female epigyne
Female, mouth
Female
Female
Female
Male
Male
Male
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