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Orb weavers or Orb-web spiders

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Araneidae: Orb weavers or Orb-web spiders This is a large family of large to small-sized spiders. The araneid or typical orb-weaving spiders are distributed all over the world. They are spinners of orb webs and are called “orb-weavers” or “orb-web spiders”. Almost all the species construct orb-webs of various size, complexity and inclination though most are vertical or near vertical; in the heights above ground and also in houses, buildings, etc.; but they are not foliage, either high upon the trees or in shrubs, herbs or grasses at various ground dwellers. The orb-webs have geometrical precision and beauty. Many of araneids having no retreats, merely run away from the web or drop to the ground them build nest-like retreat by folding a leaf or bunch of leaves, a little away from the web and directly connected with the web centre by threads. The when disturbed. If undisturbed, they climb up to the webs by means of thread consisting of many concentric rings and series of radii, which the

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

St. Andrew’s Cross Spider: Argiope pulchella (Thorell 1881)

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St. Andrew’s Cross Spider  Sc. Name: Argiope pulchella  (Thorell 1881) Family: Araneidae (Total length: ♂ 3.5-4.5 mm, ♀ 8.0-12.0 mm) (Plate 6.g-i) This is a common spider in the mangroves, evergreen, hill and sal forests. This is a diurnal species and builds vertical orb-web suspended within 20-400 cm from the ground surface. The web of this spider can be easily recognized due to the presence of X-shaped zigzag band stabilimentum or X-shaped shield cross bands of white silk in the centre of the web. This brilliant coloured spider sits in the web hub keeping head downward and holds its legs in pairs such a way that they appear aligned to the four arms of the letter ‘X’. Sometimes only one cross band or part of its arm is found in the web centre. Distribution: Bangladesh: Sundarbans mangroves, Lawacherra, Madhavkunda, Shahzibazar, Raghunandan, Barkal, Pablakhali, Bhawal sal forests, Dhaka, Kushtia, Jamalpur; India, Myanmar, Vietnam, Singapore, Malaysia, Indonesia. Argiope sapoa Barri