Latrodectus mactans, known as southern black widow or simply black widow, and the shoe-button spider, is a venomous species of spider in the genus Latrodectus. The females are well known for their distinctive black and red coloring and for the fact that they will occasionally eat their mates after reproduction. The species is native to North America. The venom can cause pain and other symptoms, but is rarely fatal to healthy humans.
The redback spider, also known as the Australian black widow, is a species of highly venomous spider believed to originate in South Australia or adjacent Western Australian deserts, but now found throughout Australia, Southeast Asia and New Zealand, with colonies elsewhere outside Australia. It is a member of the cosmopolitan genus Latrodectus, the widow spiders. The adult female is easily recognised by her spherical black body with a prominent red stripe on the upper side of her abdomen and an hourglass-shaped red/orange streak on the underside. Females usually have a body length of about 10 millimetres (0.4 in), while the male is much smaller, being only 3–4 mm (0.12–0.16 in) long.
The katipō is an endangered species of spider native to New Zealand. It is one of many species in the genus Latrodectus, such as the Australian redback, and the North American black widow. The species is venomous to humans, capable of delivering a potentially dangerous bite. It is a small to medium-sized spider, with the female having a round black or brown pea-sized body. Red katipō females found in the South Island and the lower half of the North Island, are always black, and their abdomen has a distinctive red stripe bordered in white. In black katipō females found in the upper half of the North Island, this stripe is absent, pale, yellow, or replaced with cream-coloured blotches. These two forms were previously thought to be separate species. The male is much smaller than the female and quite different in appearance: white with black stripes and red diamond-shaped markings. Katipō are mainly found living in sand dunes close to the seashore. They are found throughout most of coastal New Zealand except the far south and west. Katipō feed mainly on ground dwelling insects, caught in an irregular tangled web spun amongst dune plants or other debris.
Heteropoda venatoria is a species of spider in the family Sparassidae, the huntsman spiders. It is native to the tropical regions of the world, and it is present in some subtropical areas as an introduced species. Its common names include giant crab spider, banana huntsman spider or cane spider.
Latrodectus geometricus, commonly known as the brown widow, brown button spider, grey widow, brown black widow, house button spider or geometric button spider, is one of the widow spiders in the genus Latrodectus. As such, it is a 'cousin' to the more infamous Latrodectus mactans. L. geometricus has black and white patterns on the sides of its abdomen as well as an orange-yellow colored hourglass shape marking. Their eggs are easily identified by points that project from all over the egg sacs. L. geometricus are found all over the world, but are believed to originate in Africa or South America. Their bites, though painful, are not considered to be dangerous.
The giant house spider has been treated as either one species, under the name Eratigena atrica, or as three species, E. atrica, E. duellica and E. saeva. As of April 2020, the three species view was accepted by the World Spider Catalog. They are among the largest spiders of Central and Northern Europe. They were previously placed in the genus Tegenaria. In 2013, they were moved to the new genus Eratigena as the single species Eratigena atrica. In 2018, the three separate species were restored. The bite of these species does not pose a threat to humans or pets, and they are generally reluctant to bite, preferring instead to hide or escape.
Steatoda grossa, commonly known as the cupboard spider, the dark comb-footed spider, the brown house spider, or the false widow or false black widow, is a common species of spider in the genus Steatoda.
Steatoda nobilis is a spider in the genus Steatoda, known in the United Kingdom as the noble false widow, as it superficially resembles and is frequently mistaken for the black widow and other spiders in the genus Latrodectus. It is often referred to as thefalse widow, although "false widow" is a more general term applied to a wider group of species with this resemblance. It is a moderately medically significant spider, with most bites resulting in symptoms similar to a bee or wasp sting. Some bites may cause more significant harm, partly due to pathogenic bacteria from the spiders.
Argiope aurantia is a species of spider, commonly known as the yellow garden spider, black and yellow garden spider, golden garden spider, writing spider, zigzag spider, zipper spider, black and yellow argiope, corn spider, Steeler spider, or McKinley spider. The species was first described by Hippolyte Lucas in 1833. It is common to the contiguous United States, Hawaii, southern Canada, Mexico, and Central America. It has distinctive yellow and black markings on the abdomen and a mostly white cephalothorax. Its scientific Latin name translates to "gilded silver-face". The body length of males range from 5–9 mm (0.20–0.35 in); females range from 19–28 mm (0.75–1.10 in). These spiders may bite if disturbed or harassed, but the venom is harmless to non-allergic humans, roughly equivalent to a bumblebee sting in intensity.
Phidippus audax, the bold jumper or bold jumping spider, is a common species of spider belonging to the genus Phidippus, a group of jumping spiders easily identified by their large eyes and their iridescent chelicerae. Like all jumping spiders, they have excellent stereoscopic vision that aids them in stalking prey and facilitates visual communication with potential mates during courting. Bold jumping spiders are native to North America and have been introduced to Hawaii, Nicobar Islands, Azores, and the Netherlands. They are typically black with a distinct white triangle on their abdomen.
Theridion grallator, also known as the Hawaiian happy-face spider, is a spider in the family Theridiidae that resides on the Hawaiian Islands. T. grallator gets its vernacular name of "Hawaiian happy-face spider" from the unique patterns superimposed on its abdomen, specifically those that resemble a human smiling face. T. grallator is particularly notable because of its wide range of polymorphisms that may be studied to allow a better understanding of evolutionary mechanisms. In addition to the variety of color polymorphisms present, T. grallator demonstrates the interesting quality of diet-induced color change, in which its appearance temporarily changes as it metabolizes various food items.
Peucetia viridans, the green lynx spider, is a bright-green lynx spider usually found on green plants. It is the largest North American species in the family Oxyopidae. This spider is common in the southern U.S., Mexico, Central America, and in many West Indies islands, especially Jamaica. Lynx spiders are hunters specialized for living on plants. This species does not use a web to capture its prey. It pounces on its prey in a cat-like manner, which is the reason for the name lynx. It is active during the day.
Hysterocrates gigas is a member of the tarantula family, Theraphosidae found in Cameroon. It is known as the giant baboon spider, Cameroon red baboon spider, or red baboon tarantula.
Stenolemus lanipes is a species of thread-legged bug (Emesinae).
The numerical response in ecology is the change in predator density as a function of change in prey density. The term numerical response was coined by M. E. Solomon in 1949. It is associated with the functional response, which is the change in predator's rate of prey consumption with change in prey density. As Holling notes, total predation can be expressed as a combination of functional and numerical response. The numerical response has two mechanisms: the demographic response and the aggregational response. The numerical response is not necessarily proportional to the change in prey density, usually resulting in a time lag between prey and predator populations. For example, there is often a scarcity of predators when the prey population is increasing.
Spiders are air-breathing arthropods that have eight legs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude silk. They are the largest order of arachnids and rank seventh in total species diversity among all orders of organisms. Spiders are found worldwide on every continent except for Antarctica, and have become established in nearly every land habitat. As of August 2022, 50,356 spider species in 132 families have been recorded by taxonomists. However, there has been debate among scientists about how families should be classified, with over 20 different classifications proposed since 1900.
Crossopriza lyoni is a widespread species of cellar spiders that prefer to live in or around human structures. They are commonly known as tailed cellar spiders, tailed daddy longlegs spiders, and sometimes box spiders. They all possess extremely long fragile legs that can reach up to 6 cm (2.4 in) long and a body length of that ranges from 2.5 to 7 mm. Their abdomens are distinctly squarish when viewed from the side and their carapace is more or less circular when viewed from above. They also possess two kinds of sound-producing organs and have six eyes.
Pisaurina mira, also known as the American nursery web spider, is a species of spider in the family Pisauridae. They are often mistaken for wolf spiders (Lycosidae) due to their physical resemblance. P. mira is distinguished by its unique eye arrangement of two rows.
Anelosimus jabaquara is a species of spider found in subtropical, humid, lowland forests in Brazil. Anelosimus jabaquara was first described by Herbert W. Levi in 1956. These spiders cooperate to spin and repair the colonial web, capture prey, and care for the brood. Colony size is small, and the sex ratio is biased towards females.
Pardosa pseudoannulata, a member of a group of species referred to as wolf-spiders, is a non-web-building spider belonging to the family Lycosidae. P. pseudoannulata are wandering spiders that track and ambush prey and display sexual cannibalism. They are commonly encountered in farmlands across China and other East Asian countries. Their venom has properties that helps it function as an effective insecticide, and it is, therefore, a crucial pesticide control agent.
