Go to National Library of New Zealand Te Puna Mātauranga o Aotearoa
Volume 53, 1921
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Araneus orientalis Urquhart.

With regard to this very beautiful species, de Dalmas maintains, probably correctly, that the male described under this name by Urquhart is really that of Araneus brouni; but I wish to point out that the female of A. orientalis is indubitably a distinct species, however much the males may have been confused. This conclusion is based on the following bionomic and morphological characters:—

The nest, built in captivity in a single night, is almost exactly like that of A. pustulosus, but is slightly larger and rather more than a hemisphere. Its silk is dark grey-green in colour, quite different from the flaming orange fabric of A. brouni. The flat base is built on a foundation of strong white silk. The female spider which constructed this nest agreed in every detail with the description of A. orientalis (female) of Urquhart. In addition, after nest-building she regained her appetite and recovered completely,

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after the manner of A. pustulosus, but contrary to the ascertained habit of A. brouni. From the much commoner A. pustulosus, A. orientalis is readily distinguished by her heavily annulated legs and the two pronounced antero-dorsal prominences of the abdomen, in both of which characters she approaches A. brouni. She differs from both in the almost complete absence of a posterior prominence.

With regard to the epigyne, Urquhart (Trans. N.Z. Inst., vol. 20, p. 121, 1888) gives the following description: “In mature examples a black, somewhat oval, rather pointed, deep-margined lip about half as broad as long, one-fourth longer than breadth of vulva, projects backwards from beneath the semi-pendulous process of the corpus vulvae.” Three mature females have been carefully examined, and the external genitalia found to agree substantially with Urquhart's description. The long grooved lip is especially noticeable and very distinct from anything possessed by A. brouni or A. pustulosus. The parts are a deep, shining black. (See figure.)

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Araneus orientalis: ♀ Epigyne. × 18.

While the pattern of the abdomen seems constant, the ground-colour may be a deep velvey reddish or an equally lustrous green, the whole effect rendering Urquhart's name singularly appropriate. Recent experience also has corroborated Urquhart's statements both with regard to the subglobose, dark-green cocoon, and the scanty irregularity of the web. The male has not yet been found. Mature females occurred at Wanganui in March and early April.