Badumna longinqua or the grey house spider is a species of spiders in the family Desidae. Native to eastern Australia, it has been introduced into New Zealand, Japan, the United States, Mexico, and Uruguay.
Description
Badumna longinqua is an average-sized spider, with males attaining a maximum length of no more than , while females are marginally larger with a maximum body length of . Its common name, grey house spider, is due to colouration on the cephalothorax and abdomen, which are carpeted with light-grey hairs and spot-like markings and legs, which are purplish-brown in colour with hairs arranged into stripes on each leg. The similarly coloured brown carapace darkens nearer the chelicerae and eyes. Its eight eyes are small and black, with the front middle pair exceptionally larger at approximately 1 and a half times the size of surrounding eyes. Underneath these setae is an ovate abdomen and legs, which are purplish-brown in colour with hairs arranged into stripes on each leg.
Distribution
New Zealand range
Badumna longinqua was originally native to eastern Australia. The spider was unintentionally introduced and colonised into New Zealand and now is widespread throughout both the North and South Islands. This species is found throughout the North Island but is selected within the South Island as it is not as common southern and western of the South Island due to unfavourable environmental conditions. The colonisation of this species has increased over the last few decades due to human transport and trade, most likely arriving during colonial times, via inert phoresy on ships, planes, trains, and merchandise. The species was only first reported in New Zealand in the twentieth century. The range expansion of the species is due to human activities. This is because Badumna longinqua is able to spread within goods in transportation such as ships, trains and planes, which, offer warmth and the availability of food. Another speculated arrival method is that of ballooning, a means of dispersal in Araneae where a spiderling lets out a thread of silk called gossamer, which is carried away by wind or a thermal updraft, causing the spider to become airborne. Badumna insignis, a closely related, slightly larger species, commonly named the common black spider or black house spider, has also colonised New Zealand, but only as far as the northern part of the North Island.
Geographic distribution
Aside from Australasia, B. longinqua has increased its global range to other countries including Argentina, Brazil, Germany, Japan, the United States, Uruguay, and South Africa
Habitat preferences
Badumna longinqua is mainly located in temperate zones or climates of the world. Temperate zones or climates are in the middle latitudes, which are found between the tropics and the polar regions. Environmental conditions can limit the success of a species but Badumna longinqua shows great tolerance and survival for varied climates. In most foreign nations including New Zealand, the grey house spider is a synanthropic species and is common in urban habitats and agroecosystems. The species resides almost exclusively in the somewhat artificial environments that are produced as a result of human inhabitancy, and not in wild habitats, for example natural forest. The distinctively messy web of B. longinqua can be found in many urban places, such as nooks and crannies on window frames and walls, in rubbish bins, under furniture, on car bodies and mirrors, trees bases and benches in urban parks, and artificial posies in cemeteries. Badumna longinqua have also been found in cemeteries in artificial flowers, which therefore suggest that they are very suitable to refuge. The species primarily are found living in tree trunks, rock walls, retreats, leaves, and tangled webbing in green shrubs. Badumna longinqua live in grasslands, riparian forests and wetlands. Higher densities of the species populations are found in trees near roads or urban areas where human activity is higher. Commercial Eucalyptus plantations in Uruguay, and Pinus plantations elsewhere provide an abundance of potential homes for the spiders, which often take up residence on the trees, positioning their hideaways under loose bark. In the United States, Badumna longinqua seems to be less reliant on a synanthropic relationship with people and can also be located in woodlands, along immediate coastal areas, within agricultural ecosystems, and recently in vineyards.