T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network


Nursery web spider (Dolomedes minor)

Kingdom: Animalia
Phylum: Arthropoda
Class: Arachnida
Order: Araneae
Family: Pisauridae
Genus: Dolomedes
Species: D. minor
Scientific name: Dolomedes minor
Common name: Nursery Spider

Nursery web spiders are large and fast-moving  with a leg span of six centimetres or more in adult females. Males are somewhat smaller. These spiders are typically pale brown or grayish in colour with yellow bordering around the cephalothorax (the frontal portion of the spider that bears the legs, fangs, and eyes). 
The D. minor species typically has a substantial yellowish stripe running lengthwise from the front to the middle of the abdomen (the rear portion of the spider). .They can be found throughout New Zealand.

Nursery web spiders are known for their webs, yet they do not use them to catch prey. The webs of these spiders are a common sight on gorse and other shrubs and are, as the name suggests, literally nurseries for young spiderlings.During summer, the female nursery web spider can be seen roaming about carrying a large white ball underneath her. This is her egg sac and she carries it everywhere in her fangs until her young are ready to emerge. When this time comes, she takes the egg sac to the top of a tree or shrub and constructs the nurseryweb. The mother stays close, and during the day can often be found near the base of the plant where she has deposited her young. Secure inside the nurseryweb, the young spiderlings emerge from the eggsac and remain here for about a week or so before dispersing by ballooning.

Dolomedes minor actively hunt and scavenge for food at night. The prey spectrum of the spider consists of a variety of small organisms including locusts, other spiders, Dobson fly larvae, earthworms, bees and other small insects.

 



Female
  



Male, demonstrating the ability to walk on water






The Dolomedes minor spider in the photo below has a leg span of 6 cm.

Close up of a Dolomedes minor head showing fangs and palps. The palps in the front are used for sensory purposes. In the male the palps are modified for putting sperm into the epigyne of the female, that is situated on the underside of the abdomen. The jaws are located below the eyes and are called chelicera. The piercing parts of these jaws are the fangs that deliver the venom via a small hole at its tip. 






Dorsal view of a Dolomedes minor.


Ventral view of a female Dolomedes minor


A juvenile nursery spider

A nursery spiders nurseryweb and her eggsac inside

Inside a nursery spiders nurseryweb  The egg sac from which the spiderlings have left can be seen bottom left.

The spidering have obtained the adult shape and are just about to disperse by ballooning