Spider & Insect Information
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Chilean Recluse INTRODUCTION: On 7 July 2002, an infestation of the Chilean recluse, Loxosceles laeta (Nicolet), was discovered in a residence in Winter Haven, Polk County, Florida. Recluse spiders are rare in Florida: the native brown recluse, Loxosceles reclusa Gertsch and Mulaik, is known from a few scattered localities in five northern Florida counties; and the Mediterranean recluse, Loxosceles rufescens (Dufour), has been recorded from three counties in central and southern Florida, but has apparently been eradicated. The current infestation of the Chilean recluse has been treated. But the fact remains that this spider, a world traveler, has made it here once and may turn up again. DESCRIPTION: While similar in appearance to other recluse spiders, the Chilean recluse is
larger with a body length up to 15 mm (5/8 in.). They are pale yellow to reddish brown. The carapace (head region) usually has a dark violin-shaped marking which is often difficult to see. This mark cannot be used reliably to identify recluses, as some harmless Florida spiders have similar markings. See our Entomology Circular No. 406 for more information on how to distinguish our native spiders from recluse spiders. BIOLOGY: Members of the genus Loxosceles are nocturnal and not aggressive to people.
In nature, they live under rocks, inside logs or in any place that may serve as a shelter.
They also live in dark, undisturbed places in houses. The female, who can reproduce up to
five times a year, lays about 50 eggs per sac and can make multiple (usually up to 5) debris-covered eggsacs. It takes 9-12 months for a spider to mature and it can live up to 7 years. DISTRIBUTION: Loxosceles laeta is native to Ecuador, Peru, Chile, Argentina, Uruguay, and southern and eastern Brazil. It has been introduced into Belize, Guatemala, Finland, and the United States (several records from Los Angeles, California; one record from Kansas; and a population in one building at Harvard University, Cambridge, Massachusetts). MEDICAL IMPORTANCE: The Chilean recluse is reputedly the most toxic species of Loxosceles, which have necrotizing venom, and it has been implicated in a few deaths in
South America. The spider and its venom are under study at the Instituto Butantan in São Paulo, Brazil. SUSPECTED RECLUSE? Homeowners should keep in mind that many common, harmless spiders look similar to the Chilean recluse, and that thus far it is only known from one home in Florida. Nevertheless, if presence of the Chilean recluse is strongly suspected, specimens should be submitted to the Department of Agriculture's Division of Plant Industry for confirmation.
To send a specimen for identification, the spider should first be killed with a household pesticide labeled for use on spiders. DO NOT HANDLE THE SPIDER AND DO NOT SQUASH IT. Once certain the spider is dead, using tweezers, place it in a tightly-sealed leakproof container
(such as a 35mm film canister) along with a cotton ball soaked in some regular rubbing alcohol, and mail (along with complete contact information where you may be reached if your specimen is positively identified as a Chilean recluse) in a small, padded box or envelope to Entomology, Division of Plant Industry, PO Box 147100, Gainesville, FL 32614-7100.
Black Widow Spider (approx. 1/2" long) Jet black and shiny, a black widow spider usually has
a distinctive red mark or marks under the abdomen. It makes an irregular web in dark places such as foundations, air vents, shrubs and woodpiles, often at ground level. Black widows are one of the poisonous spiders found in North America and occur in all 48 states from Mexico to Canada. The venom of the Black Widow is 15 times stronger than that of a rattlesnake. The black widow spider is widely feared because its bite results in severe pain that may take several days to subside. Such bites are rarely fatal but small children and elderly persons are
at risk. This spider is uniformly shiny black in color and has a large spherical abdomen. The key identifying character is the red hourglass-shaped mark on the underside of the abdomen. When webs are visible, inspect carefully before putting your hand down under an object.
Black widows prefer to construct their webs in secluded, protected sites where insects are
more likely to show up. Such clutter creates innumerable spaces suitable for spider harborages. The best control for all SPIDERS is by using a SPIDER-B-GONE® system.
Brown Widow Spider The Brown Widow Spider is found throughout the world and is very abundant in Florida. The body and legs vary in color from fawn to black. In most specimens there are lighter colored markings along the sides of the abdomen. The hourglass-shaped marking on the underside is red or yellow. The egg-sac of the Brown Widow is fawn colored and spherical, with many points radiating from the surface, rather like a World War II marine mine. The web is an untidy, irregular tangle of strong silk, formed into a deep, tough scoop. The spider rests with its egg-sacs at the back of the web. Brown Widows have been found
in association with human structures: under tables and chairs, in car bodies, among paperwork on desks and in the bases of pot plants. The Brown Widow is the most actively reproducing widow species, producing up to 5000 young per female per season. It appears not to be as adversely affected by winter and has the potential to become a considerable pest. The venom of a Brown Widow is TWICE as strong as the Black Widows or 30 times that of a rattlesnake.
Brown Recluse Spider (approx. 1/2" long) Light brown or gray brown, with a violin shaped
mark (photo on the right) on its back. It lives like a recluse in a small web in dark corners, running to hide when disturbed. The bite usually results in an ulcerous sore, that may become serious if bacterial infection occurs because of lack of medical attention. The brown recluse spider is often called the "violin" spider or "fiddle back" spider because of
the distinctive fiddle-shaped marking on top of its cephalothorax (head end to which the legs are attached). A further identifying character is the fact that this spider has only six eyes, instead of eight, and these are arranged in three pairs of two eyes at the front of the head. This spider is feared because its bite can result in open, ulcerating sores. (SEE PHOTO BELOW) Left untreated, such bites often become infected and significant tissue necrosis can occur.
It is always best if someone thinks they may have a spider bite that he or she seek medical attention. This is especially true in areas where brown recluse spiders are common.
Like most spiders, the brown recluse spider does not seek to bite people... the bite is usually accidental. The spider crawls into a shoe, into clothing or into a bed and a person then puts
on the clothing or lies on the spider in bed. The spider, being trapped, has only one defense
and that is to bite. Unfortunately, the bite of this spider produces a nasty result in people.
 This is an AEDES mosquito. This is just one of several that carry the
WEST NILE VIRUS.
This is a FLEA. Even if you DO NOT have any pets, your yard could still be hosting fleas. Fleas (order Siphonaptera) are one of the major groups of
blood-sucking insects. At present approximately 2000 species and subspecies of fleas are known. Adult fleas are obligatory hematophages parasitizing mammals and birds.
PAPERWASPS are brownish or brown with yellow stripes and a narrow waist. They usually
do not nest in the ground but make paper comb nests under the eves of your home, barn or garage. Unlike honey bees, they can sting several times, due to their smooth sting apparatus.
YELLOW JACKET Bright yellow and black markings, no hair. Nests in holes
in the ground, cavities in walls, etc., 500-5,000 workers/colony. Scavenges
on food: the "picnic pest." It can sting several times with its smooth stinger. Can cause dangerous stings in the throat if swallowed after it has invaded a soda can or bottle.
 MUD DAUBERS Mud daubers are medium sized (1-1.5 inch) wasps with the front portion of the abdomen being long and highly constricted, giving them a "thread-waisted" appearance. These wasps do not defend their nests and are not likely to attack people. Mud dauber nests are constructed of mud or clay and often are found attached to the walls or under the eves of buildings.
 HOUSEFLY Size: 1/6 - 1/4 inch long. (It is often challenging to recognize flies from a picture. Because different species may need to be treated differently, be sure a fly problem is correctly identified before attempting control.) They are found around the outside and occasionally inside buildings during summer. It can be a nuisance when it congregates around the outside
of buildings in large numbers. It can potentially contaminate food with disease causing bacteria.
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