Denizens Of The Desert:
Desert Bighorn And Near Relatives
Battle Of The Reptiles
Latrodectus, The Poisonous
Le Conte Thrasher
Gnatcatchers And Verdins
Desert White–crowned Sparrow
Read More Articles About: Denizens Of The Desert
Latrodectus, The Poisonous
( Originally Published Early 1900's )
OF all the spiders feared by man to-day few have the black reputation of those belonging to the genus Latrodectus. The much-feared malmignatte of southern Europe, the dreaded karakurte of southeastern Russia, the kapito of New Zealand, the vancoho of Madagascar, and our own American black widow are all spiders of this genus. The American Latrodectus is quite generally known on sight by the Southwestern Indians, especially the older ones; for it was long the practice among these people to use these spiders, crushed, for poisoning their arrow-points; but I am convinced that not nine out of ten of the white people who need to fear this noxious spider would know her if they saw her, and this in spite of the fact that she is one of our commonest Southwestern spiders.
Latrodectus is one of our few spiders with a purely black body. So black is it that often it shines like blackest satin and under certain lights even has a greenish cast. The red spots so much talked of in connection with this spider, and which are necessary marks for her identification, are found on the underside of the abdomen. These are not always red, but are quite as often only buff or a light corn color, a fact well to keep in mind. They are in the shape of two triangles set apex to apex and resemble together an old-fashioned hour-glass; hence the vernacular name for the species, "hour-glass spider." Sometimes on the back of the spider there is a broken row of red dots running down the middle of the back. The malle spider, who is also black, has, besides the red markings, four pairs of red stripes running down the sides of the abdomen. The female Latrodectus is a comparatively large spider with an abdomen often fully as large as a gooseberry or a large shoe button. The Widow's husband is much smaller, generally only about one fourth as large as his mate; he is seldom seen.
In accordance with her rapacious nature this spider exhibits few aesthetic tastes in the building of her web. It is an unshapely and unbeautiful piece of construction, made of threads exceedingly coarse; in fact so coarse that one may detect the presence of the black widow by her web alone. No set pattern is used in its making; a few silken strands which she has run criss-cross with a more or less carelessly made funnel-shaped, more closely woven retreat, built in some dark corner, is all there is to the crude structure.
When egg-laying time comes a small, globular, closely woven, rather hard, silken sack is made, filled with tiny eggs and suspended by several threads to the main web. Owing to the collection of dust it is often a dirty white color. The eggs soon hatch after being laid, but the young do not necessarily emerge just then. Sometimes they remain within the egg case many days and moult before coming out; further, they always wait for a sunny day to come before showing themselves. They are at first a light yellowish gray color, but after a number of, moults turn black like the parents. Unlike the young lycosid spiders, who cling to the mother and ride about for some time on her back and legs, the young black widows show their independence as soon as they are out of the egg case. Both eggs and young may be found in the Southwestern States at almost any time of the year.
The poison of this venomous spider is secreted in two pouchlike glands covered; with spirally arranged muscles. These glands are located at the extreme front end of the head, and from them run tiny ducts to the pores at the ends of the claws of the mandibles. The pore is located not at the point of the claw, where it would become closed or plugged by the flesh of the victim, but on one side, allowing the venom to run freely after the puncture has been made by the sharp end of the mandible. This opening of the venom duct may be seen with the naked eye on the mandible of such large spiders as the black tarantulas.
When a human being is bitten there is little to show where the puncture has been made - no little red spot as is often thought. Since the poison is one of the most virulent known to medical science, the symptoms following a bite are quite serious, especially if the victim is a small child or a person in frail health. In such cases death may ensue. In most cases, however, the patient recovers after a few days of torture. According to temperament and other conditions which may prevail, different persons are affected differently. There are two types of symptoms following the bite: the nervous and the muscular.
Dr. John C. King, of Banning, California, who has treated an unusual number of patients suffering from this spider's bite, in a paper recently read before his medical society, speaks of the severity of the nervous symptoms as follows :
"The pain is excruciating, often requiring morphia. It is the type of pain we meet in severe cases of neuritis and angina pectoris. It travels from the part bitten, regardless of situation, toward the heart. The patients often lose self-control, weep, cry out, and become difficult to manage. The nervous symptoms, as pain, twitching, insomnia, and nervous prostration, sometimes continue for weeks. I have treated bites inflicted by tarantulas and stings given by scorpions, but in no such instance has the pain compared with that following this small spider's bite, nor have the nervous symptoms been so marked.
"Personally I prefer the bite of a rattler."
In some cases the bite of Latrodectus is followed by extreme tightening of the abdominal muscles, few of the nervous symptoms then being present. All of the abdominal muscles, especially the short muscles of the hips, become exceedingly rigid and the pain accompanying this tonic spasm is intense. The pain subsides after about forty-eight hours and no after effects are noticed. The poison never seems to affect the heart.
Though this spider is much feared by the Indians, it is now known that, at least to some extent, the venom was formerly used by them as a cure for acute and chronic rheumatism and a number of other ailments. A medicine man at Cahuilla, Riverside County, California, who used this remedy, prepared his patient for the bite by a fast of two days and then allowed the spider to bite the sufferer on the hand. The patients who took this heroic treatment became very sick, but were said to be free afterwards from their old ailment. The case of a white settler who took the treatment from the Cahuillan medicine man, and was cured, came to my attention just recently.
The black widow, or hour-glass spider, is widely distributed in the United States, being found, according to Emerton, "all over the United States as far north as New Hampshire and south through Florida, the West Indies, and Chili." It is very plentiful in Southern California. In spite of its frequency, few people are bitten. The spiders seldom bite unless severely provoked. In almost every case of which I can find authentic record, the persons bitten were those living in country districts and the bite was experienced while about out-of-door toilets or barns where these spiders resort to spin their webs across openings and in dark corners.