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Metellina merianae  (Scopoli, 1763) (Half-light orb weaver)
≤ 1900   1901-1979   1980-2005   2006 ≤
Description: Carapace light brown with dark triangle covering head. Within the triangle there is a pair of light patches about midway between the ocular area and the fovea. Irregular blackish bands are present along the margins of the carapace. Foveal area also blackish with a few radiating dark streaks. Legs are yellowish brown more or less clearly annulated with greyish brown. Base of leg spines are ringed with black. The abdomen is yellowish brown mottled with plenty of dark brown. At a distance the abdomen may appear greenish grey. Ventrally, there is a pair of elongated light patches at side of spinners. In addition, the colour variety Metellina merianae celata has a golden median band running the whole length of abdomen. At close look the golden band is made up of patches of yellow and red as well as some white reticulated areas. Only four specimens of the golden striped variety are known from the Faroes. Assuming that ca.1000 specimens of the normal form have been collected on the island (410 by Brændegård, 1928) a rough estimation of the ratio between the two forms possible: 1000:4 = 250. That is ca. 0.4 %.of the population of Metellina merianae occur in golden striped variety. Size: Female 5.5-8.5 mm; male 5-7 mm.

Genus: Metellina Chamberlin & Ivie, 1941. Characters of genus: Very closely related to the Meta genus. The differences between the genera Metellina and Meta are not visible with a lens. Anterior row of eyes recurved, posterior straight. Chelicerae are provided with 3 large promarginal teeth and retromargin with 2 large teeth and 2 denticles (Almquist 2005). Endites are about twice as long as labium. Paracymbium sclerotized. The ventral markings sometimes consist of a broad dark median band flanked by reticulated narrow white bands.

Family: Tetragnathidae Menge, 1866 (Long-jawed Orb Weavers). Characters of family: The tetragnathids belong to the group of ecribellate spider families having 8 eyes and 3 tarsal claws. Many members of the family are usually elongated spiders characterized by the often very long legs and chelicerae (subfamilies Tetragnathinae and Leucauginae). However there are some genera with oval abdomens or normal sized chelicerae (subfamily Metinae). Males are usually smaller and slimmer than females who often have the base of the abdomen swollen. Males often have relatively longer chelicerae than females and sometimes they are even longer than the carapace. The male chelicerae are also often furnished with spurs on their chelicerae, which are used to lock the female chelicerae during mating. The female palp is provided with a well-developed, toothed claw. The eyes are not unlike those of the araneids. They are subequal and arranged in 2 rows of 4 usually equidistant or with the medial eyes closer to each other than to the lateral eyes. The lateral eyes are either spaced apart or contiguous, sometimes situated on a tubercle. The primary eyes are always black. The secondary eyes of most genera are provided with a light-reflecting layer (tapetum) aiding nocturnal vision. However, tapetum is missing in a few genera such as Tetragnatha having all eyes black. The carapace is elongate and with short, shallow fovea (indistinct in Tetragnatha). The sternum is longer than wide and pointed at rear, sometimes protruding in between coxae IV. Narrow, horizontal sclerites are sometimes present between coxae and carapace. Endites are parallel and may either converge or dilate in front of the rebordered labium. The legs are long and slender and mostly with spines but in some genera there are none (for example Pachygnathy). The trichobothria are often branched. They are sometimes arranged in rows. The shape of the abdomen is variable sometimes round or oval but mostly elongate. Colours vary, quite often with bright white, green, red and yellow colours often with coppery or silvery blotches. Tetragnathids are entelegyne or secondary haplogyne (without epigyne). Sometimes the genital plate is not sclerotized (subfamily Tetragnathinae) and thus adult females may be difficult to separate from subadults and juveniles since there is no epigyne - just a hairy, tongue-shaped plate projecting posteriorly from the epigastric fold. The male palp is simple and often very similar within genera.
Female
Female
Female
Female
Subadult male
Subadult male
Subadult male
Female
Female
Female
Female
Male
Male
Male
Palp and epigyne
Small juvenile
Small juvenile
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