Araneus alsine, Pink orb weaver

Araneus alsine (Walckenaer, 1802) (Pink orb weaver)

≤ 1900

1901-1979

1980-2005

2006 ≤

Description: The beautiful Pink Orb Weaver is easily overlooked since the species often hides in a retreat consisting of dried leaves spun together to form an inverted cone. The retreat and web is found in low vegetation, often near bushes of Bog Whortleberry (Vaccinium uliginosum). Size: Female ? mm; male ? mm.

Genus: Araneus Clerck, 1757. (Angulate and round-shouldered orb weavers). Characters of genus: Small to large large spiders ranging from 2.5 mm to at least 25 mm body length. Posterior medial eyes slightly larger than the rest and separated by one diameter from each other. Anterior medials separated by 2-3 diameters. Height of clypeus ca. 1.5 diameter of one anterior medial eye. Some species have well-developed shoulder humps while other are round-shouldered or possess traces of humps such as Araneus diadematus. There is some sexual dimorphism with males smaller and much slimmer than females, especially gravid ones. Epigyne with large scape originating from base of epigyne. Male palp complex, the shape of embolus and terminal apophysis being the most important characters for separating the species (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.