common house spider

not listed

NNA - Not applicable

not listed

Common house spider is a medium-sized colorful comb-footed spider. It has a cosmopolitan distribution, occurring on every continent except Antarctica. In the United States it is common east of the Great Plains and west of the Rocky Mountains, uncommon between. It is found in and around human dwellings, sheds, barns, and privies, in stables, under highway bridges, and in culverts.

Females are 3⁄16″ to ¼″ (5 to 6 mm) in length and have a legspan of ⅝″ to ¾″ (15 to 20 mm). Males are smaller, ⅛″ to 3⁄16″ (3.8 to 4.7 mm) in length.

The front part of the body (cephalothorax) is flat, short, slightly longer than wide, narrow in front, and highest in the middle. The upper side (carapace) is yellowish-brown, usually darker in the middle. It is shiny and has few hairs.

There are eight eyes arranged in two parallel rows of four eyes each. The front (anterior) row is slightly curved forward when viewed from the front, and the rear (posterior) row is straight or slightly curved backward when viewed from above. On each side the lateral eyes are widely separated from the middle (median) eyes and are almost touching each other. All of the eyes are small. The anterior median eyes (AME) are slightly larger and are dark, while the rest of the eyes are pearly. The jaws (chelicerae) have no teeth.

The abdomen is large and bulbous, higher than long, and pointed downward at the end. It is variable in color, dirty white or gray with white and dark brown to almost black patches markings. There is a dark horizontal line just before the highest point, white chevrons before the line, a white spot just behind the highest point, and dark chevrons behind the spot. On lighter individuals the markings are indistinct. On the male the abdomen is more slender.

The legs are medium-length, slender, and spiny, and have many hairs. On the female they are yellow with dark bands. On the male they are orangish. The first pair of legs is the longest, the third pair is the shortest. On the female, the fourth pair is longer than the second pair. On the male that is reversed, the second pair is longer than the fourth pair. There is a row of 6 to 10 slightly curved bristles (“comb”) on the last segment (tarsus) of each hind leg. This is the feature that gives the family one of its common names. There are three claws at the end of each tarsus, but these are not visible to the naked eye.

Female Body Length: 3⁄16″ to ¼″ (5 to 6 mm)

Male Body Length: ⅛″ to 3⁄16″ (3.8 to 4.7 mm)

Legspan: ⅝″ to ¾″ (15 to 20 mm)

The spider constructs a web consisting of an irregular network of sticky strands. The web is often built in upper angles of rooms and in corners of window frames and doorways. The spider does not build a retreat.

In and around human dwellings, sheds, barns, and privies, in stables, under highway bridges, and in culverts.

Year-round when indoors. It cannot survive northern winters outdoors.

The spider hunts at night, hanging upside-down in the middle of the web. During the day it retreats into a corner or a crack.

The egg sac is tan and pear-shaped. It is hung in the web.

Sources

24, 29, 30, 82.

Very common in eastern United States, less common in Minnesota.

This spider was formerly classified as Theridium tepidariorum. In 1950 it was moved to the genus Parasteatoda, in 1955 to the genus Achaearanea, and in 2006 back to the resurrected genus Parasteatoda.

Location: Albany, NY

Location: Albany, NY

Location: Albany, NY

Location: Woodbury, MN

Location: Woodbury, MN