Mouse Spider

Structure, Appearance and Characteristics

• Crawling / Hunting Spider.
• Body size (approx.): Female: 20-25mm, Male: 12-18mm.
• Small and black.
• Pale area at the base of the abdomen on the dorsal surface.
• Female is larger than male and uniformly black.
• Cephalothorax enlarged.
• Carapace glossy.
• Head area is high, broad and bulbous and slopes steeply down towards the abdomen.
• Fangs enlarged.
• Eyes widespread across the front.
• Spinnerets short and blunt.
• Short, thick legs.
• Males wander during summer / autumn especially after rain. Will wander even during day over considerable distances.
• Females and immature spiders remain hidden in the burrows.
• Non-aggressive.
• When disturbed, will assume the characteristic defence stance and if provoked will plunge forward with their large fangs.
• Lives 1-3 years.

Habitat

Occurs in all parts of New Zealand and are often referred to as the true Trapdoor spider. The name “mouse” comes from its burrowing tendencies. This species lives in tunnels (vertical burrows) in the ground. Female constructs a burrow which may be provided with a silken floor. The burrow is vertical, oval at the top, round at the bottom, approx. 30cm deep. Burrows can have one or two doors. A horizontal shaft is often constructed leading off the main burrow with a vertically hinged door. This shaft serves as a “brood chamber”. The male appears to move about freely, with little evidence of burrowing tendencies.

Pest Status

Fangs are strong so bite is painful. Several bites have been recorded without serious effects. Localised swelling with some pain, burning or itchiness at the site of the bite have been recorded. No recorded fatalities from bites. Adults are normally considered the pest but should be considered as useful because they feeds on other insects.