Monday, October 1, 2012

WOLF SPIDERS (Family Lycosidae)


Wolf Spiders are some of the most common spiders encountered in the bush in Kenya.  Many species are large and conspicuous, and therefore easy to find (if you’re looking).  Some species are free-living, wandering spiders, while others live in burrows or horizontal sheet webs in short grass.
Wolf Spiders have a very distinct eye pattern (see the close-up photo).  They have two large eyes on the top and to the sides of their cephalothorax.  They have another two large, forward-facing eyes at the vertical front of the cephalothorax, and a further 4 smaller eyes in a horizontal line below them.  If confusion ever arises between a Wolf Spider and a Baboon Spider, look at the eye pattern to determine the difference.  Wolf spiders come in all sizes from tiny to very large.  

Happily, Wolf Spiders’ venom is not harmful to man.

Above: Lycosa sp. WOLF SPIDER.  Close up shot to show distinctive Lycosid eye pattern.  Notice two large eyes laterally placed on top of head, two large eyes front, and four small in a flat (sometimes recurved) line below.  Large chelicerae (fang bases) protrude vertically from below the eyes.  Pedipalps (those small leg-looking things on either side of the chelicerae) and legs have long sensitive "hairs" used as sensory organs.

 Above: Lycosa sp. - BURROWING WOLF SPIDER.  These Lycosids live in vertical burrows in the ground, usually with no cap/trapdoor above the hole.  Females stay close to their burrows even at night when out foraging for food.  Males often wander in search of food and mates.  Some of these can be very large and to the un-trained eye can be confused with Baboon Spiders (Theraphosidae).  However, the eye pattern  is always indicative and easy to see even from a distance.
 Above: Lycosa sp. - BURROWING WOLF SPIDER.  Wolf Spider females attach their egg sacs under the back of their abdomen.  Once the spiderlings hatch, they climb up on their mother's back until they have gone through about 2 moults (instars), similar to scorpions.  If they fall off while she is wandering around on the ground, they simply climb back up one of her legs.
 Above: Hippasa sp. - SHEET WEB WOLF SPIDER.  These Lycosids live on wide flat sheet webs that terminate in a tunnel to a safety retreat in the grass.  The web is constructed in low grass, close to the substrate.  When disturbed on threatened, the spider retreats into the tunnel.  Notice the superb camouflage of the spotted body on a dew-soaked web early in the morning.  These spiders are web bound and do not wander in search of food.
 Above: Hogna sp. - WANDERING WOLF SPIDER.  These are free-living spiders that do not live in burrows or webs.  Often found in leaf litter and short grass in bush and forest habitats.

Above: (Probably) Hogna sp. - WANDERING WOLF SPIDER. Often found in or near buildings.  Completely Harmless.  Notice the front right leg is missing.  With each moult, this leg will slowly begin to grow back.

No comments:

Post a Comment