Mastophora extraordinaria

Mastophora extraordinaria is a species of spider in the orb-weaver spider family Araneidae. It is found in South America (Brazil, Uruguay and Argentina).^[1] Like some other species of the genus Mastophora, adult females resemble bird droppings. Mastophora species, including M. extraordinaria, are "bolas spiders" – adult females capture their prey by using a sticky drop on the end of a single line which they swing at the target, usually a male moth attracted by the release of an analogue of the attractant sex pheromone produced by the female moth. Juveniles and adult males do not use a bolas, catching prey with their legs alone.^[2]

Mastophora extraordinaria
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Chelicerata
Class:	Arachnida
Order:	Araneae
Infraorder:	Araneomorphae
Family:	Araneidae
Genus:	Mastophora
Species:	M. extraordinaria
Binomial name
Mastophora extraordinaria Holmberg, 1876[1]

Description

Herbert W. Levi described a female in 2003 (males were not known). The total length of the specimen's body was 12 mm (1⁄2 in). Other females ranged from 9.5 to 14 mm (3⁄8 to 9⁄16 in). The carapace was 4.8 mm (3⁄16 in) long and almost as wide in the thoracic region. The carapace was dark brown with a narrow white rim and had low tubercules. The abdomen was white with two black patches on the upper surface and a white square underneath. It had a pair of humps. The combined length of the patella and tibia of the first leg was a little more than the width of the carapace at 5 mm (3⁄16 in).^[3]

Taxonomy

The species was first described in 1876 by E.L. Holmberg, an Argentine biologist. It is the type species of the genus.^[1] Its resemblance to a bird dropping was such that Holmberg first thought of using the specific name ornithocoproides ('resembling a bird dropping'), but replaced it by extraordinaria, noting its singular aspect.^[4] The genus has been placed in the broadly defined subfamily Cyrtarachninae,^[5] and within this in the informal group of mastophorines which includes the bolas spiders.^[6]

Distribution

The species is found in southern Brazil, Uruguay and northern Argentina.^[3]