Neogea nocticolor (Thorell, 1887)

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Neogea nocticolor (Thorell, 1887)

Family: Araneidae (Orb weavers or Orb-web spiders)

Neogea nocticolor (Thorell, 1887) was found to construct vertical or inclined vertical web in the exposed or partially exposed small vegetation of the forests within about 0.5-1.5 m on the ground. The spider was found to sit at the hub of the web keeping head downward. This species added a special type of spiral ribbon stabilimentum in the web and the ribbons were arranged in a strange fashion. The device was found in about 40% of the webs of this species. The widest length of the stabilimentum was 5.6-6.7 cm along with the horizontal diameter and 1.9-2.3 cm along with the vertical diameter of the web. The spider sits on the upper portion of the device where the circular ribbons seem to join at a point (Figs. 1 and 2). The stabilimentum was found in the webs constructed on low vegetation, equally illuminated by direct sunlight most of the day and partly shaded in the morning or afternoon.

Some members of this species was found to add vertical diagonal band stabilimentum in its web, suspended in small gewa plants of the mangrove forests. The web was observed about 20m inside from the forest edge, shaded by the foliage of the large trees. The web was suspended vertically and the spider was found to rest in the hub keeping head downward. A conspicuous, silk white diagonal band was added vertically along the hub of the web, leaving a gap in the hub where the spider fills-up the gap exactly in the line of the stabilimentum (Fig. 3). First and second pairs of the legs of the spider are thrust out in front and the third and fourth pair similarly stretched out backward. This attitude gives the spider a linear appearance and makes it appear part of the stabilimental band. Many barrier threads were found to fix with the vegetation and small, sticky and conspicuous white silk dots were found on these barrier threads. The whole adjustment looks perfect for the purpose of concealment. The sticky barrier threads with sticky silk dots may probably save the web from unwanted invaders, e.g. large insect, small predatory birds, etc.

Fig. 1 Patterns of stabilimenta in the web of Neogea nocticolor (Thorell, 1887)

Fig. 2 Patterns of stabilimenta in the web of Neogea nocticolor (Thorell, 1887)

Fig. 3 Patterns of stabilimenta in the web of Neogea nocticolor (Thorell, 1887)

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