Common spiders of New York. (2024)

Spiders evoke a combination of curiosity and horror in people ofall ages. Spiders' seeming ability to appear suddenly out ofnowhere on their fine silk lines can startle anyone. But theirfrightening reputation is largely undeserved. Spiders are fascinatingcreatures! The webs of many species are intricate architectural wonders.They are superb predators that capture more prey than all otherterrestrial predators combined. Spiders can be masters ofstealth--blending into their surroundings or hiding so well that theyare often overlooked.

While both insects and spiders are in the phylum Arthropoda,spiders are in the class Arachnida, which also contains scorpions,harvestmen, pseudoscorpions and ticks. All spiders (order Araneae) haveeight legs, two body segments (cephalothorax and abdomen) separated by awaist, and unlike the insects, they do not have chewing mouthparts,antennae or wings. Spider jaws are called chelicerae, and include hollowfangs through which they inject venom to immobilize or kill their prey.

Spiders prey on small living invertebrates, such as insects orother spiders. Unable to swallow solid food, spiders liquefy their preyexternally by regurgitating digestive juices onto it. They then crushthe prey with their chelicerae and suck up the juices. Spiders have apair of jointed appendages (called pedipalps or palps) on either side ofthe chelicerae that look like short legs. Palps help manipulate the preyduring feeding.

Like all arthropods, spiders have a hard exoskeleton with flexiblemembranes at the joints so that the legs can bend. To grow larger, theymolt, shedding the old exoskeleton and then sucking in air to inflatethe soft underlying skeleton until it hardens at a larger size. Spidersmolt up to a dozen times until they become sexually mature adults.

All spiders produce silk--thin, incredibly strong protein strandsproduced from various glands in the abdomen and extruded throughmicroscopic spigots arranged on muscular spinnerets, which are locatedat the tip of the abdomen. Depending on the gland used, silk hasdifferent properties: some is sticky for catching prey; but most arenon-sticky and are used to cover egg sacs, construct parts of webs, wrapprey, or make waterproof retreats. While not all spiders use silk tocapture prey, they all use silk to produce draglines, two fine strandsthat are continuously released wherever the spider walks. Many smallspiders use these lines to disperse long distances, simply extruding abit of dragline into the breeze which carries them away.

Spiders mate in a way that is unique in the animal kingdom. When amale becomes sexually mature, the ends of his palps develop into swollenstructures that function as small, complex syringes. Before courting afemale, the male constructs a small web on which he deposits a drop ofsperm. He then sucks up the sperm into each of his "palpsyringes" which are then used to inseminate the female. Mating is arisky business for males as female spiders of many species attempt tocannibalize males after mating.

In New York's northern climate, spiders typically live onlyone year. Most pass the winter as eggs that develop into adults insummer and then die in fall. However, some species overwinter asinactive adults, hiding in crevices under bark, or stones, or in windowcasem*nts. To avoid the lethal effects of freezing solid, they secreteantifreeze into their blood. In spring, they complete their life cycleby mating, laying eggs, and dying.

sheet web weavers

Linyphiidae Often overlooked because of their small size (less thana quarter inch long), sheet web weavers are among the most abundantspiders in vegetation. They build fine, non-sticky, sheet webs invegetation. The webs are composed of a lace-like horizontal web with"knock down" threads, or many fine, disorganized verticalstrands that are invisible to small flying insects, which crash into thethreads and fall onto the sheet. The spiders run upside down on theunderside of their webs and bite prey through the web. Some localspecies may vary the shape of the sheet web. One species, called the"bowl and doily" spider, weaves a cup-shaped web above thehorizontal sheet and hangs from the bowl. Another, called the"filmy dome" spider, weaves a dome under which it lurks.(Pictured above is Linyphia marginata.)

Are daddy-long-legs spiders?

Harvestmen (or "daddy-long-legs")

and ticks are not true spiders, but spider relatives. All threetypes of animals are arachnids, but harvestmen and ticks have only onebody segment, whereas spiders have two. Harvestmen have oval bodies andlong, thin legs. They are omnivores that hunt small insects, scavenge ondecaying material, or feed on plant juices. They do not have venom, butcan produce a foul smelling scent. Ticks are external parasites thatsuck blood from reptiles, birds or mammals. They are typically flat withvery short legs that barely-protrude beyond the body. If they haverecently taken a blood meal, the body may swell up to the size of a limabean.

funnel web or grass spiders

Agelenidae Grass spiders build sturdy, non-sticky sheet webs with afew "knock down" threads on top of vegetation. One corner ofthe sheet tapers into a silken funnel where the spider waits facingoutward for insect prey to land on the sheet. Once an insect lands, thespider dashes out on top of the sheet and bites the prey before it cantake off again. Grass spiders are about three quarters of an inch long,with brown bodies and long conspicuous spinnerets. They can be spottedon low hedges or evergreen plantings around buildings. (Pictured aboveis the grass spider or funnel weaver, Agelenopsis sp.)

cellar spiders

Pholcidae Cellar spiders have extremely long, delicate legs and anarrow, elongated body. They hang upside down in a very loose web ofdisorganized threads on wails close to the ceiling of homes. Afterlaying a cluster of about a dozen eggs, the female wraps it with a fewstrands of silk and carries it in her fangs. When threatened, manyspecies rapidly gyrate in the web and become an almost invisible blur.It is an urban legend that these spiders are extremely poisonous.

American house spider

Theridiidae--Achaearanea tepidariorum The American house spider isthe most commonly seen species of cobweb spider found around homes. Mostcobweb spiders can be identified by their large, round, shiny abdomens,relatively thin legs, and their tendency to hang upside down in messycobwebs that are attached to the structure by a few sticky threads. Thewebs are built where there is protection from the elements. Femalecobweb spiders produce light brown, spherical egg sacs that hang in theweb. The venomous black widow spider with its shiny, black abdomen andred hour-glass design is a cobweb spider, but is extremely rare in NewYork.

nocturnal orb weaving spiders

Araneidae Nocturnally active, these spiders build orb webs anywherethat night flying insects, such as moths, are active. Favorite locationsare near porch lights or other well-lit areas. Most Araneus are brown,with two bumps on the front of their abdomens. The cross spider has aseries of white spots on its abdomen in the shape of a cross. Themarbled spider, A. marmoreus, is boldly patterned and lives in fieldsrather than around man-made structures. During the day. these spiderscan be found hiding in a retreat made from a curled leaf tied togetherwith silk. The retreat is generally located above the remains of theprevious night's web, connected to it by a silk thread. (Picturedabove is the cross spider, Araneus diadematus.)

jumping spiders

Saiticidae Jumping spiders are easily identified by their largeeyes. squat bodies and sturdy legs. They are very intelligent, colorfulspiders with distinct personalities. Jumping spiders have excellentvision and will often turn to look at you as you approach. They huntduring the day, eating insects and other spiders. They get their namefrom their ability to jump impressive distances while searching invegetation or catching prey. Before jumping, these spiders will touchtheir abdomens to the ground to tack down their draglines. That way ifthey miss their destination, their spinnerets clamp the silk so theyonly fall a short distance. When jumping spiders see prey that theycannot jump onto directly, they are known to take a detour route throughthe vegetation to put them into a position above the intended prey. Malejumping spiders court females by moving their brightly coloredchelicerae, palps or leg tufts. In autumn, many jumping spiders buildsilken retreats in goldenrod plants, windowsills, or mailboxes.(Pictured above is the common jumping spider, Phidippus audax.)

crab spiders

Thomisidae Crab spiders get their name from the way hey hold theirlegs out to their sides and walk with a crab-like scuttle. The first twopair of legs are often greatly enlarged, making them even more crab-likein appearance. These spiders do not build webs. but wait motionless forprey to come within close range. Many species hunt on flowers forinsects, such as bees, flies, and butterflies, using their fast-acting,powerful venom to quickly paralyze them. Many crab spiders are capableof camouflaging themselves to match the flower's color by changingtheir color to white, yellow, or pink over several days. One of the bestways to find these spiders is to look on flowers for immobile insectssituated at an odd angle. Upon closer inspection you will see the insectin the jaws of a crab spider.

wolf spider

Lycosidae Wolf spiders are named for their tendency to be slightlyfurry, brown or grey spiders that run after their prey. They have longsturdy legs and good vision from two of their eight enlarged eyes. Theabundant wolf spiders forage on the ground or in the lower parts ofplants at night. Female wolf spiders carry light-colored, spherical eggsacs attached to their spinnerets. Once hatched, the spiderlings clingto hairs on their mother's abdomen for about a week. When you goout at night, look at the ground in front of you with a flashlight heldnext to your head at the same level as your eyes. You can see manysilvery blue-green spots reflecting back at you from the eyes ofnumerous wolf spiders in the grass.

There are about 40,000 identified spider species worldwide. Thiscan make properly identifying an individual tricky. By focusing oncertain physical traits you should be able to narrow down to the group.For instance, the shape of the abdomen, relative sturdiness of the legs,or eye patterns are often characteristic of a specific group. Likewise,the presence and shape of a web are important clues. Spiders living inwebs are built differently than their non-web living relatives who mustsupport their weight against gravity while walking. Knowing aspider's habitat is also informative--fishing spiders live nearwater, crab spiders hunt in flowers, while cellar spiders are commonnear ceilings in homes.

fishing or nursery web spiders

Pisauridae Nursery web spiders resemble wolf spiders, but havesmaller eyes and legs that are held more widely to the sides of theirbody. They get their name from the fact that some species fish foraquatic prey, such as insects, crustaceans, or even small minnows.Standing on the banks of streams or ponds with their legs lightlytouching the water, the spiders feel for vibrations from passing preyand then quickly dive into the water to pursue it. Other species of thisspider hunt vertically on vegetation or basem*nt walls. Fishing ornursery web spiders build a characteristic "nursery" web invegetation, where they guard their egg sacs and spiderlings. (Picturedabove is Dolomedes triton.)

sac Spiders

Clubionidae, Miturgidae Sac spiders are typically light coloredspiders with noticeably protruding spinnerets and dark fangs. They weavesmall silk sacs under rocks or loose bark that they use for sleepingretreats and rearing young. Sac spiders lack capture webs, and wander invegetation and occasionally in homes looking for prey. There are twofamily groups of sac spiders. Two species of small, pale, yellowspiders, called yellow sac spiders Cheiracanthium mildei (pictured here)and C. inclusum, are the only spiders in New York that are moderatelypoisonous to humans. They have necrotic venom that causes itchy orpainful ulcerating sores that are slow to heal. In New York, bitesattributed to brown recluse spiders are almost certainly from yellow sacspiders.

black & yellow garden spider

Araneidae: Argiope aurantia One of the largest, most conspicuousspiders in New York, the diurnally active black and yellow garden spideroccurs in sunny fields and gardens. Like all orb weavers, its web is anarchitectural wonder, designed to greatly extend the spider'ssensory system while using a minimal amount of silk to trap or slow downflying prey. The web has several parts: non-sticky spokes (radii) andlines that frame the web provide structural support; the sticky spiralensnares flying insects; and the broad swaths of white zigzag silk deterbirds from flying through it. The web is rebuilt each morning to refreshglue on the spiral. Large prey items are wrapped and immobilized withbroad bands of swathing silk. Sexually dimorphic, adult females arehundreds of times larger than the tiny males.

This brochure contains 11 species and groups of spiders that aremost commonly encountered in New York. For additional help identifyingspiders, you should purchase a guide at a local bookstore or search theinternet for spiders.

Text by Linda Rayor and Cole Gilbert, Department of Entomology,Cornell University: Artwork by Patricia Kernan, NYS Museum; Layoutdesign by Frank Herec