The Wolf Spider

Common Name:
Wolf Spiders
Scientific Name:
Lycosa spp.
Class/Order/Family:
Arachnida/Araneae/Lycosidae
Metamorphosis:
Simple

INTRODUCTION

The common name reflects that these are hunting spiders and will chase their pray; the family name and typical genus Lycosa are from the Greek word for wolf. These spiders are often big and hairy which alarms some people, but they are primarily nuisance pests. Over 100 species occur in the United States and Canada. This section will be restricted to members of the genus Lycosa (over 30 spp.) which contains the large and hairy species of wolf spiders.

RECOGNITION

Adult female body length 3/8-1 3/8" (9-35 mm), male body length 1/4-3/4" (6-20 mm); cephatothorax and abdomen very hairy. Color usually dark brown, often with paler stripes or markings, or sometimes yellow with dark stripes or markings. With 8 dark eyes, front row of 4 small, evenly spaced, eyes slightly curved towards rear medially, posterior row strongly curved forward medially forming 2 rows, center/f ront 2 eyes very large and lateral/posterior 2 eyes of intermediate size; appear as 3 rows of 4, 2 and 2. Cephalothorax (in lateral view) with front eye area raised above posterior half. Chelicerae moderately long, strong, with 3 teeth on fang furrow retromargin (side opposing fang). Labium longer than wide. Abdomen with posterior spinnerets at most only slightly longer than anterior ones. Legs long and spiny, tibias of 1st and 2nd pair of legs with last pair of ventral spines apical, tibia of 4th pair of legs with 3 spines of about equal thickness/stoutness across dorsum, and metatarsus (lst tarsal segment/6th segment from body) of 4th leg less or not longer than its tibia and patella (segment between femur and tibia) combined. Tarsi with 3 claws each, center claw very small.

SIMILAR GROUPS

  1. Other genera of wolf spiders (Lycosidae) without the above combination of characters, and usually smaller.

  2. Nursery web and fishing spiders (Pisauridae) with 8 eyes about equal in size, front row of 4 slightly curved downward/forward, and female carries egg sac in her chelicerae Oaws).

  3. Lynx spiders (Oxyopidae) with 6 large eyes forming a hexagon and 2 smaller eyes below, and abdomen pointed.

  4. Ground spiders (Gnaphosidae) with posterior row of 4 small eyes almost straight, front spinnerets cylindrical and separated, and abdomen long and somewhat flattened.

REPRESENTATIVE SPECIES

  1. Lycosa aspersa Hentz. Adult female body length 3/4-1 " (18-25 mm), male 5/8-3/4' (16-18 mm); color brown, carapace (cephalothorax dorsum) dark brown with gray haire (somewhat lighter in males to yellowish brown) and without distinct markings except for a distinct narrow line of yellow hairs in eye region, abdomen brown with slightly darkef median longitudinal stripe, venter black but spotted, and legs annulate/ringed; usually builds a burrow in ground; found in New England and adjacent Canada south to Florida and west to Nebraska.

  2. Lycosa carolinansis Waickenaer. Adult female body length 7/8-1 3/8" (22-35 mm) with a leg span of about 3" (75 mm), male body length 3/4" (18-20 mm); color brown carapace (cephalothorax dorsum) dark brown with gray hairs (lighter in males to light silvery gray) and without distinct markings, abdomen brownish with slightly darkei median longitudinal stripe, and venter blackish; usually builds burrow in ground; founc throughout the United States.

  3. Lycosa punctulata Hentz. Adult female body length 7/16-5/8" (1 1-1 7 mm), male 1/2-5/8" (13-15 mm); color yellow with brownish to black longitudinal stripes, carapace (cephalothorax dorsum) with 2 submedial stripes, abdomen with I wide median stripe and 1 narrow lateral stripe in basal half on each side, and venter spotted; found in Nem England south to Florida and west to Rocky Mountains.

  4. Lycosa rabida Waickenaer. Adult female body length 5/8-7/8" (16-21 mm), male about 7/16" (I I mm); color yellow with brownish to black longitudinal stripes, carapace (cephalothorax dorsum) with 2 submedial stripes, abdomen with 1 wide median stripe enclosing lighter areas and 1 narrower lateral stripe solid in basal half and solid or a,, dots in apical/posterior half, venter not spotted, and male with lst pair of legs dark browr to black; no burrow; found in New England to Florida and west to Oklahoma an( Nebraska.


BIOLOGY

The egg sac is spherical, consisting of an upper and lower half united at the middle. It is carried on the female's spinnerets and is usually white, sometimes green, bu changes to dirty gray or dirty brown with age.

In the New England states, Lycosa carolinensis females lay their eggs in June anc July. The egg sac is about 1/2" (1 2 mm) in diameter contains about 100-1 35 eggs (range to 600 per sac). The mother bites open the egg sac allowing the enclosed spiderlings tc emerge and crawl onto her body where they stay for a week or longer; they usually emerge in June and July. They attain about half their growth by the succeeding winter and become adults the following year. Mating occurs in the autumn with males dying before winter. Females overwinter, lay their eggs the next May-June, and may live for a 3rd year.

In the New England states, Lycosa rabida females lay their eggs in August to mid- October. The egg sac is about 5/16-3/8" (7.5-10 mm) in diameter and contains 168-365 eggs. Upon emerging, the spiderlings crawl onto their mother's body where they have been observed until mid-October. They become adults the following summer with mating occurring in August. Females live until frost.

HABITS

Wolf spiders actively hunt during the night and sometimes during the day. They are fast on their feet and pursue prey. Because of these habits, they are commonly seen by people. Wolf spiders often alarm people because they are big, hairy, and run fast.

Some wolf spider species build retreats consisting of either a shallow excavation under a stone, or a tube/burrow running vertically or diagonally into the ground. They leave their burrows primarily at night to hunt insect prey in the surrounding area. Some species build web retreats or shelters when with young, but they do not build snare webs.

Outside, they can be found under stones, landscape timbers, firewood, under decks, in leaf lifter, etc. They often rest in such sheltered places during the day.

These spiders may enter structures in search of prey. Although they are not inclined to be permanent residents in structures, once inside, they often stay. Inside, they tend to stay at or near floor level, especially along walls under furniture and other objects. Wolf spiders may be brought indoors with firewood.