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Misumenops celer

What do they look like?

Like other members of their family (Thomisidae), their first two pairs of legs are much longer than their third and fourth pair, and are held out in a crab-like position; this is where their common name comes from. Female swift crab spiders are larger than males. Females are usually 1.65 mm wide, while males are 1.28 mm wide. Adults are yellow or yellowish-white, with dark stripes on each side of their cephalothorax, which is the fused head and thorax section of their body. Males are usually darker than females, and have red bands around their legs. Females have a double row of red dots at the end of their abdomen, while males have two dark lines that form a V-shape. Some individuals have other red or black patterns on their abdomen. Swift crab spiders also have a thick covering of bristle-like hairs on their body. Adult females generally weigh about 28.1 mg. Their eggs are yellow and 0.75 mm in diameter. Newly hatched spiderlings have a white or transparent cephalothorax, white legs, and a yellowish abdomen. Their bodies are smooth, with no markings or hairs. In their next stage of maturity, they are yellowish, with many hairs on their body. (Anderson, 1996; Bradley, 2012; Branson, 1966; Marshall and Gittleman, 1994; Muniappan and Chada, 1970; Prenter, et al., 1999)

  • Sexual Dimorphism
  • female larger
  • sexes colored or patterned differently
  • Average mass
    0.028 g
    0.00 oz
  • Average basal metabolic rate
    0.011 cm3.O2/g/hr

Where do they live?

Swift crab spiders (Misumenops celer) are from the Nearctic region. They are found across the United States, as far south as Texas and Florida, and from coast to coast. They are the most common species of their genus (Misumenops) on the west coast. They are also very common in Canada, especially in southern British Columbia, Alberta, and Saskatchewan. They have also been found in Mexico. (Bradley, 2012; Johnson, 1996; Knutson and Gilstrap, 1989; McIver and Belnavis, 1986)

What kind of habitat do they need?

Swift crab spiders are usually found on shrubs, flowers, and small trees, as well as on many crop species. They are generally found on plants that grow in meadows, forests, agricultural fields, and on plant-covered dunes. (Gregory Jr, et al., 1989; Johnson, 1996; Knutson and Gilstrap, 1989; McIver and Belnavis, 1986)

How do they grow?

Eggs of swift crab spiders are laid in an egg sac, and stay there for 5 to 11 days. After hatching, spiderlings are still attached to the egg by the end of their abdomen and remain inside the membrane for another 1 to 2 days. During this time, they keep their legs close to their bodies and remain still. During their first developmental stage, known as their first instar, spiders leave the membrane, but they stay in the egg sac. At this point, they cannot walk or stand on smooth surfaces. About 23 days after their egg is laid, swift crab spiders develop into second instar spiderlings and leave the egg sac. They are active after this point. Males usually go through 4 or 5 instars, while females go through 6 or 7 instars before reaching maturity. Their 2nd instar lasts for 27.1 days on average, their 3rd lasts 41.8 days, their 4th lasts 50.4 days, their 5th lasts 43.7 days, their 6th lasts 45.1 days, and finally their 7th lasts 17.0 days. Both juveniles and adult swift crab spiders are found at the same time during the summer. They usually have two population peaks during the year, one in July when overwintered spiderlings reach maturity, and another in late August. Males live an additional 35 to 64 days after reaching adulthood, while females live about a year after laying eggs. (Corey and Taylor, 1989; Dowdy, 1955; Johnson, 1996; Knutson and Gilstrap, 1989; Muniappan and Chada, 1970)

How do they reproduce?

A day after their last molt, male swift crab spiders ready for mating and build a triangular web inside their mating chamber. Females also ready themselves for mating soon after their last molt, sometimes as quickly as 1 hour after. When a male spots a female, he vibrates his abdomen, moving his first 2 pairs of legs and palpi (an appendage near his mouth), and slowly approaches her. He touches her legs with his first and second pair of legs. If the female is receptive, she lifts her legs and allows herself to hang from the web. There is usually little or no pre-mating activity. After mating, the male usually stays with the female until she becomes active. Swift crab spiders are polygynous, so males mate with more than one female. Females only mate once, and then a waxy coating covers the opening of their genital structure, which prevents more mating. They usually mate in mid-summer. (Muniappan and Chada, 1970)

Female swift crab spiders do not lay eggs until 11 to 43 days after mating, 23 days on average. By this point, her male mate is long gone, either cannibalized, mating with new females, or dead. Four to 10 days before laying her eggs, females make a white sheet of web. This becomes a large sac, and this is where she lays her eggs. Females lay their eggs at night. The eggs are covered in silk, creating an egg sac. One sac contains an average of 145 eggs. A single egg weighs 0.28 mg on average. One female usually makes two egg sacs in her lifetime. Eggs incubate in the sac for 5 to 11 days before hatching. About 23 days after the eggs are laid, spiderlings enter their second development stage, known as an instar, and they leave the egg sac. Females stay near the egg sac until their offspring leave. Males usually reach maturity after 4 or 5 instars, while females reach maturity after 6 or 7 instars. (Marshall and Gittleman, 1994; Muniappan and Chada, 1970)

  • How often does reproduction occur?
    Female swift crab spiders breed once in their lives, while males mate multiple times.
  • Breeding season
    Swift crab spiders breed during mid-summer.
  • Range number of offspring
    55 to 700
  • Average number of offspring
  • Range gestation period
    5 to 11 days
  • Average time to independence
    23 days

Adult swift crab spiders likely provide nutrients in their eggs for their offspring to grow and develop. Females build an egg sac for each clutch to provide protection. Females also stay with the egg sac until the spiderlings are ready to leave, which is typically about 23 days after the eggs are laid. This is also likely for protection. Males do not provide any parental care, as they may be cannibalized after mating. Males move on to other mates and typically die much sooner than females. (Muniappan and Chada, 1970)

  • Parental Investment
  • female parental care
  • pre-hatching/birth
    • provisioning
    • protecting
      • female
  • pre-independence
    • protecting
      • female

How long do they live?

It can take swift crab spiders 100 to over 200 days to fully develop into adults after hatching. Once they reach adulthood, males usually live another 35 to 64 days, while females can live another year after laying her eggs. (Muniappan and Chada, 1970)

  • Typical lifespan
    Status: wild
    135 to 365+ days
  • Typical lifespan
    Status: captivity
    135 to 365+ days

How do they behave?

Swift crab spiders mostly mate and hunt at night, although they are sometimes active during the day. They are 'sit and wait' predators. They can usually be found on flowers and the upper parts of crop plants, where they catch insects. On flowers, they use their silken drag line to tie several flower petals together to form 'bowers', where they sit and wait for prey. They prepare for attack by raising their first pair of legs, and then snatch the insect. They pierce the prey and paralyze them with venom. Females are usually better predators than males, probably because they are bigger. Females may also cannibalize their mates. This species does not build webs, except egg sacs and webs for mating. Swift crab spiders are solitary. This species overwinters, and can often be found on herbs, shrubs, and in dead leaf litter. (Dowdy, 1955; Gregory Jr, et al., 1989; Knutson and Gilstrap, 1989; Muniappan and Chada, 1970; Ott, et al., 1998)

Home Range

Swift crab spiders probably stay close to the flowers and plants on which they hunt. Their range is limited to how far they can walk. (Muniappan and Chada, 1970; Ott, et al., 1998)

How do they communicate with each other?

Swift crab spiders have eight eyes and view their environment visually. Their sense of touch is also important when catching prey or communicating during mating. Male often show their interest by stroking the female's front legs with their own legs. Other crab spiders use chemical cues to choose hunting sites, such as particular flowers, this is likely true for swift crab spiders as well. (Branson, 1966; Krell and Kramer, 1998; Muniappan and Chada, 1970)

What do they eat?

Swift crab spiders are predatory insectivores. They feed on many insects species, including many pest species. They are 'sit and wait' predators; they sit inside flowers and crop plants and prey on the insects that visit the plant, such as flies, butterflies, dragonflies, hemipterans, grasshoppers, and wasps and bees. They also prey on crop pests like aphids, whiteflies including silverleaf whiteflies, velvet bean caterpillars, a major soybean pest, and cotton fleahoppers, a major cotton pest. After capturing their prey, swift crab spiders paralyze them with venom. They eat the head and insides of their prey first, and then they eat the abdomen, thorax, and legs. Spiders in their first development stage do not feed. Other young spiders tend to eat smaller prey, while adults eat larger prey. (Breene, et al., 1990; Gregory Jr, et al., 1989; Hagler, et al., 2004; Knutson and Gilstrap, 1989; Muniappan and Chada, 1970)

  • Animal Foods
  • insects

What eats them and how do they avoid being eaten?

Mud-dauber wasps from family Sphecidae prey on swift crab spiders. Captured spiders are paralyzed and left in the wasp's nest with the wasp's egg. After hatching, young wasps eat the spider. Spider wasps from family Pompilidae also use swift crab spiders as larval food. Young spiders are often preyed on by insects. Once they become adults, they have very few predators. (Evans, 1964; Muma and Jeffers, 1945; Muniappan and Chada, 1970)

What roles do they have in the ecosystem?

Swift crab spiders are significant predators, feeding on many insect species. They also feed on many crop pests, which helps control the population sizes of these pests. They are also preyed on by several wasp species that use them to provide food for their offspring. (Breene, et al., 1990; Evans, 1964; Knutson and Gilstrap, 1989; Muma and Jeffers, 1945; Muniappan and Chada, 1970)

Do they cause problems?

There are no known adverse effects of swift crab spiders on humans.

How do they interact with us?

Since swift crab spiders feed on many important insect crop pests, they can help control the pest populations. This helps decrease crop damage and economic losses. They are considered an important predator in grain, sorghum, and cotton fields. They have also been found in corn, soybean, alfalfa, peppermint, and peanut fields. (Agnew, et al., 1985; Hagler, et al., 2004; Knutson and Gilstrap, 1989; McIver and Belnavis, 1986)

  • Ways that people benefit from these animals:
  • controls pest population

Are they endangered?

Swift crab spiders have no special conservation status.

Some more information...


Angela Miner (author), Animal Diversity Web Staff, Leila Siciliano Martina (editor), Animal Diversity Web Staff.


Agnew, C., D. Dean, J. Smith Jr. 1985. Spiders collected from peanuts and non-agricultural habitats in the Texas west cross-timbers. The Southwestern Naturalist, 30/1: 1-12. Accessed August 13, 2013 at

Anderson, J. 1996. Metabolic rates of resting salticid and thomisid spiders. Journal of Arachnology, 24/2: 129-134. Accessed August 13, 2013 at

Bradley, R. 2012. Common Spiders of North America. California: University of California Press.

Branson, B. 1966. Spiders of the University of Oklahoma Biological Station, Marshall County, Oklahoma, with observations on species used by Muddaubers as larval food, and a review of the species known from Oklahoma. The Southwestern Naturalist, 11/3: 338-371. Accessed August 13, 2013 at

Breene, R., R. Sterling, M. Nyffeler. 1990. Efficacy of spider and ant predators on the cotton fleahopper [Hemiptera: Miridae]. Entomophaga, 35/3: 393-401. Accessed August 13, 2013 at

Bryant, E. 1948. Some spiders from Acapulco, Mexico. Psyche, 55: 55-77. Accessed August 13, 2013 at

Corey, D., W. Taylor. 1989. Foliage-dwelling spiders in three central Florida plant communities. Journal of Arachnology, 17/1: 97-106. Accessed August 13, 2013 at

Dowdy, W. 1955. A hibernal study of Arthropoda with reference to hibernation. Annals of the Entomological Society of America, 48/1-2: 76-83. Accessed August 13, 2013 at

Evans, H. 1964. Notes on the prey and nesting behavior of some solitary wasps of Mexico and southwestern United States (Hymenoptera: Sphecidae and Pompilidae). Journal of the Kansas Entomological Society, 37/4: 302-307. Accessed August 13, 2013 at

Gregory Jr, B., C. Barfield, G. Edwards. 1989. Spider predation on velvet bean caterpillar moths (Lepidoptera, Noctuidae) in a soybean field. Journal of Arachnology, 17/1: 120-122. Accessed August 13, 2013 at

Hagler, J., C. Jackson, R. Isaacs, S. Machtley. 2004. Foraging behavior and prey interactions by a guild of predators on various lifestages of Bemisia tabaci. Journal of Insect Science, 4/1: PMC455675. Accessed August 13, 2013 at

Johnson, S. 1996. Spiders associated with early successional stages on a Virginia barrier island. Journal of Arachnology, 24/2: 135-140. Accessed August 13, 2013 at

Knutson, A., F. Gilstrap. 1989. Predators and parasites of the Southwestern corn borer (Lepidoptera: Pyralidae) in Texas corn. Journal of the Kansas Entomological Society, 62/4: 511-520. Accessed August 13, 2013 at

Krell, F., F. Kramer. 1998. Chemical attraction of crab spiders (Araneae, Thomisidae) to a flower fragrance component. Journal of Arachnology, 26/1: 117-119. Accessed August 13, 2013 at

Marshall, S., J. Gittleman. 1994. Clutch size in spiders: Is more better?. Functional Ecology, 8/1: 118-124. Accessed August 13, 2013 at

McIver, J., D. Belnavis. 1986. A list of the spiders of peppermint in western and central Oregon. Proceedings of the Entomological Society of Washington, 88/3: 595-598. Accessed August 13, 2013 at

Muma, M., W. Jeffers. 1945. Studies of the spider prey of several mud-dauber wasps. Annals of the Entomological Society of America, 38/2: 245-255. Accessed August 13, 2013 at

Muniappan, R., H. Chada. 1970. Biology of the Crab spider, Misumenops celer. Annals of the Entomological Society of America, 63/6: 1718-1722. Accessed August 13, 2013 at

Ott, J., J. Nelson, T. Caillouet. 1998. The effect of spider-mediated flower alteration on seed production in Golden-eye phlox. The Southwestern Naturalist, 43/4: 430-436. Accessed August 13, 2013 at

Prenter, J., R. Elwood, W. Montgomery. 1999. Sexual size dimorphism and reproductive investment by female spiders: A comparative analysis. Evolution, 53/6: 1987-1994. Accessed August 13, 2013 at

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Miner, A. 2014. "Misumenops celer" (On-line), Animal Diversity Web. Accessed April 20, 2024 at

BioKIDS is sponsored in part by the Interagency Education Research Initiative. It is a partnership of the University of Michigan School of Education, University of Michigan Museum of Zoology, and the Detroit Public Schools. This material is based upon work supported by the National Science Foundation under Grant DRL-0628151.
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