Insects & spiders
What spider is this?
The web is worth more than the spider. A flat funnel in the grass, a messy tangle in a basement corner and a neat wheel across a doorway are made by three unrelated families, and the shape narrows the list before you have looked at a single marking. If there is no web, the spider is a hunter — and that is a useful answer in itself.
Only two North American spiders are medically significant: widows and the brown recluse. Both are flagged below. Recluses live in a defined range through the central and southern Midwest and are extremely rare outside it, so a "recluse bite" in California, Florida or New England is almost always something else — usually a bacterial skin infection. If a bite develops an expanding dark centre, fever or severe pain, see a doctor and take a photograph of the spider if you safely can.
Narrow it down
Showing all 31 spiders
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Black widow
Can injure youLatrodectus mactans, L. hesperus, L. variolus
Glossy, almost lacquered jet-black globe of an abdomen with a red hourglass on the underside, hanging upside down in a coarse, irregular, very strong tangle web low down in a dark sheltered spot.
In the record 9,532 georeferenced records · half of them Jul–Oct · most distinctive in November · mostly from the United States check on GBIF
How dangerous is a black widow? -
Brown widow
Handle with careLatrodectus geometricus
Tan to grey-brown with a geometric pattern on top and an orange or yellow hourglass beneath. The decisive clue is the egg sac: a pale ball covered in blunt silk spikes, like a tiny mine.
In the record 19,655 georeferenced records · half of them Jun–Oct · most distinctive in February · mostly from the United States check on GBIF
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Brown recluse
Can injure youLoxosceles reclusa
Uniform tan with no leg bands, no abdominal pattern, a dark violin shape on the head plate pointing backwards, and — the reliable character — six eyes in three pairs rather than eight.
In the record 6,189 georeferenced records · half of them Apr–Jul · most distinctive in February · mostly from the United States check on GBIF
Identifying a brown recluse properly -
Yellow sac spider
Handle with careCheiracanthium inclusum, C. mildei
Pale straw to greenish-yellow with a slightly darker stripe down the abdomen and dark tips to the jaws, spending the day in a small flat silk sac tucked into a wall-ceiling corner or a folded leaf.
In the record 803 georeferenced records · half of them Apr–Aug · most distinctive in December · mostly from Brazil check on GBIF
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Cellar spider
Pholcus phalangioides
A tiny body on absurdly long thin legs, hanging in a loose tangle in a ceiling corner. Disturb it and it vibrates the web into a blur — the behaviour is diagnostic.
In the record 79,360 georeferenced records · half of them May–Aug · most distinctive in January · mostly from Belgium check on GBIF
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Common house spider
Parasteatoda tepidariorum
A dull grey-brown bulbous abdomen with faint darker chevrons, in a messy tangle web in a window corner, often with two or three brown papery egg sacs hanging in it.
In the record 15,378 georeferenced records · half of them May–Aug · most distinctive in February · mostly from the United States check on GBIF
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Wolf spider
Hogna, Tigrosa and Rabidosa species
Big, hairy, brown and grey with lengthwise stripes, running fast on the ground rather than sitting in a web. Two of its eight eyes are much larger than the rest and glow back at a headtorch.
In the record 29,229 georeferenced records · half of them May–Aug · most distinctive in July · mostly from the United States check on GBIF
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Grass spider
Agelenopsis species
A flat horizontal sheet of dense silk in a hedge or on the lawn, with a funnel at one corner where the spider waits. Two long tail-like spinnerets project noticeably beyond the abdomen.
In the record 24,831 georeferenced records · half of them Aug–Sep · most distinctive in September · mostly from the United States check on GBIF
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Hobo spider
Eratigena agrestis
A brown funnel-web spider with a herringbone of pale chevrons on the abdomen and — unlike its relatives — plain, unbanded legs.
In the record 4,642 georeferenced records · half of them Jul–Sep · most distinctive in January · mostly from the United States check on GBIF
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Giant house spider
Eratigena atrica
The large fast brown spider that appears in a bathtub in autumn. Males wander in September and October looking for females; they cannot climb the enamel, which is why they are found stranded.
In the record 16,252 georeferenced records · half of them Jun–Sep · most distinctive in January · mostly from Germany check on GBIF
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Bold jumping spider
Phidippus audax
Compact, fuzzy, black with a white or orange triangle and two spots on the abdomen, and iridescent green or blue jaws. Two enormous forward-facing eyes; it turns to look at you, which nothing else does.
In the record 81,735 georeferenced records · half of them Mar–Jun · most distinctive in April · mostly from the United States check on GBIF
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Zebra jumping spider
Salticus scenicus
A tiny black-and-white striped jumper patrolling a sunny brick wall or windowsill in short darting runs, always trailing a silk safety line.
In the record 86,602 georeferenced records · half of them Apr–Jun · most distinctive in March · mostly from the Netherlands check on GBIF
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Black and yellow garden spider
Argiope aurantia
Big, unmistakable, silver head and a black abdomen splashed with bright yellow, sitting head-down in the middle of a large orb web with a thick zigzag ribbon of silk running through the centre.
In the record 70,101 georeferenced records · half of them Aug–Sep · most distinctive in August · mostly from the United States check on GBIF
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Banded garden spider
Argiope trifasciata
Silvery abdomen finely banded in yellow and black across its width rather than blotched, in an orb web in open grassland late in the summer.
In the record 32,212 georeferenced records · half of them Sep–Oct · most distinctive in November · mostly from the United States check on GBIF
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Cross orbweaver
Araneus diadematus
Mottled brown or orange with a clear cross of white dots on the top of the abdomen, in a classic wheel web across a doorway or between two shrubs, rebuilt nightly.
In the record 252,149 georeferenced records · half of them Aug–Sep · most distinctive in September · mostly from the Netherlands check on GBIF
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Marbled orbweaver
Araneus marmoreus
A bulbous orange or cream abdomen marbled with brown, on orange legs banded in black. The autumn form is so pumpkin-like it is sometimes called the pumpkin spider.
In the record 21,879 georeferenced records · half of them Aug–Sep · most distinctive in November · mostly from the United States check on GBIF
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Spiny-backed orbweaver
Gasteracantha cancriformis
A hard, flattened, crab-like white or yellow shell with six red or black spikes around the edge and black dots on top. Nothing else looks remotely like it.
In the record 34,539 georeferenced records · half of them Jul–Nov · most distinctive in December · mostly from the United States check on GBIF
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Spined micrathena
Micrathena gracilis
A tall, black-and-white, sharply spined abdomen in a small vertical orb web strung across a woodland trail at face height — the spider you walk into in August.
In the record 16,390 georeferenced records · half of them Jul–Aug · most distinctive in August · mostly from the United States check on GBIF
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Orchard orbweaver
Leucauge venusta
A small, elongated, silvery-green spider with lime and yellow stripes and orange spots underneath, hanging upside down in a nearly horizontal orb in shaded shrubbery.
In the record 32,131 georeferenced records · half of them May–Jun · most distinctive in June · mostly from the United States check on GBIF
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Long-jawed orbweaver
Tetragnatha species
Long, thin and stick-like with enormous jaws, resting stretched flat along a grass stem with the front legs extended forward and the back pair behind, becoming almost invisible.
In the record 72,848 georeferenced records · half of them May–Jul · most distinctive in June · mostly from the United States check on GBIF
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Golden silk orbweaver
Trichonephila clavipes
Large, elongated orange-brown body with tufts of black hair on the legs, in a huge web whose silk is visibly golden in sunlight. Called a banana spider in the southeast.
In the record 43,595 georeferenced records · half of them May–Sep · most distinctive in January · mostly from the United States check on GBIF
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Joro spider
Trichonephila clavata
Bright yellow and blue-grey banded body with red marks underneath and long black-and-yellow legs, in a very large three-dimensional golden web often built high, across driveways and porches.
In the record 20,077 georeferenced records · half of them Sep–Oct · most distinctive in November · mostly from the United States check on GBIF
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Green lynx spider
Peucetia viridans
Vivid translucent green with long spiny legs and a pointed abdomen, sitting motionless on a flower head waiting to ambush pollinators. It can spit venom a short distance when guarding eggs.
In the record 21,645 georeferenced records · half of them Jul–Sep · most distinctive in October · mostly from the United States check on GBIF
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Goldenrod crab spider
Misumena vatia
Crab-shaped, holding its long front legs open sideways, sitting inside a flower. It changes colour between white and yellow over several days to match whatever it is sitting on.
In the record 106,811 georeferenced records · half of them Jun–Jul · most distinctive in June · mostly from Germany check on GBIF
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Six-spotted fishing spider
Dolomedes triton
A big grey-brown spider with white side stripes standing on the surface film of still water, legs spread wide. It dives and stays under when disturbed.
In the record 12,771 georeferenced records · half of them Mar–Jun · most distinctive in March · mostly from the United States check on GBIF
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Dark fishing spider
Dolomedes tenebrosus
Very large, mottled brown with dark W-shaped chevrons on the abdomen and banded legs, flattened against a tree trunk, a woodpile or a basement wall.
In the record 27,370 georeferenced records · half of them May–Jul · most distinctive in May · mostly from the United States check on GBIF
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Texas brown tarantula
Aphonopelma hentzi
A genuinely large, uniformly dark brown, densely hairy spider living in a silk-lined burrow. Mass wanderings of males across roads happen every autumn in the southern Plains.
In the record 6,118 georeferenced records · half of them Apr–Aug · most distinctive in October · mostly from the United States check on GBIF
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Trapdoor spider
Ummidia species
A glossy, almost bald, dark chocolate spider with a shovel-shaped head, found only when the hinged soil-covered lid of its burrow is turned up. Males wander after rain.
In the record 1,541 georeferenced records · half of them Jun–Jul · most distinctive in June · mostly from the United States check on GBIF
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Woodlouse hunter
Dysdera crocata
A shiny red-orange head and legs with a pale grey-pink abdomen, and jaws so long and forward-projecting they look wrong for the body. Six eyes, and it eats nothing but woodlice.
In the record 22,126 georeferenced records · half of them Apr–Jul · most distinctive in February · mostly from the United States check on GBIF
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Parson spider
Herpyllus ecclesiasticus
Flat, velvety black-grey with a single white stripe down the abdomen that breaks into a comma at the rear — the shape of a clerical collar. Runs erratically across a wall or floor at night.
In the record 12,787 georeferenced records · half of them Jun–Aug · most distinctive in February · mostly from the United States check on GBIF
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Southern house spider
Kukulcania hibernalis
The female is a stout velvety charcoal spider living in a crevice with radiating tangled silk around the opening; the male is a slim tan spider with long legs that wanders indoors.
In the record 6,235 georeferenced records · half of them Feb–Jul · most distinctive in January · mostly from the United States check on GBIF
Nothing in this key matches every filter at once. That usually means one observation is off — a colour read in shade, or a size guessed rather than measured. Clear the filter you are least sure about and look again.
Read the web first
Spiders that build webs are far easier to place than spiders that hunt, because the architecture is family-specific and it does not vary with the individual. Learning five shapes covers most of what you will find around a house.
| What it looks like | Family | Typical builders |
|---|---|---|
| Vertical wheel with radiating spokes, rebuilt most nights | Araneidae, Tetragnathidae | Garden spiders, cross orbweaver, spiny-backed orbweaver, long-jawed orbweaver |
| Flat horizontal sheet with a funnel retreat at one edge | Agelenidae | Grass spiders, hobo spider, giant house spider |
| Messy three-dimensional tangle, no obvious plan | Theridiidae | Common house spider, widows, false widows |
| Loose tangle with a tiny spider on very long legs | Pholcidae | Cellar spider |
| Silk tube or lid over a hole in the ground | Ctenizidae, Theraphosidae | Trapdoor spiders, tarantulas |
| Small flat silk sac in a corner or a folded leaf | Cheiracanthiidae | Yellow sac spider |
| No web at all | Several | Wolf, jumping, crab, lynx, fishing, ground spiders |
Two shortcuts follow from this. A neat wheel across your porch light means an orb weaver, and no orb weaver in North America is dangerous. A dense, coarse, irregular tangle low down in a garage, shed or woodpile is the widow habitat, and it is worth looking at properly before you reach in.
The two that matter, and everything that gets blamed instead
North America has roughly 3,500 spider species and two groups of medical significance. Everything else either cannot break skin, does not bite, or produces a bite equivalent to a bee sting.
Widows
Look for a glossy black globular abdomen with a red hourglass on the underside, hanging upside down in a tangle web. Widow venom is a neurotoxin and the bite is systemic — cramping muscle pain that spreads from the site, sweating, and abdominal rigidity severe enough that it has been mistaken for appendicitis. Deaths are very rare, but a bite in a child, an elderly person or anyone with heart disease is a hospital visit.
Brown recluse
The recluse deserves care and gets hysteria. Three facts change how you read a suspected bite. First, the range is well mapped and narrow: roughly Kansas and Nebraska to western Ohio, south to Texas, Louisiana and Georgia. Outside it, verified recluses turn up only as rare imports. Second, the identification requires six eyes in three pairs, uniformly coloured legs with no bands, and no pattern on the abdomen — the violin is variable and by itself proves nothing. Third, most confirmed bites heal on their own; a minority ulcerate.
The clinical literature is blunt about the consequences of the panic: studies collecting "recluse bites" reported from outside the range have repeatedly found that the great majority were bacterial infections, most commonly MRSA, along with Lyme disease, diabetic ulcers, fungal infections and burns. Treating a MRSA abscess as a spider bite delays the antibiotic that would fix it. If a lesion is spreading, take it to a doctor and describe it as a skin lesion, not as a spider bite, unless you actually caught the spider.
Body plan, when there is no web to read
For the hunters, the shape and the way the animal moves are more reliable than colour.
Jumping spiders are short, compact and hairy with two huge forward-facing eyes, and they turn their whole body to look at you. Nothing else does that, and it makes them the easiest family to recognise at a glance.
Wolf spiders are long-legged, striped brown-and-grey ground runners with two big eyes in the middle row that reflect a headtorch beam back as green points. A female carrying a round egg sac attached to her spinnerets, or covered in spiderlings, is a wolf spider and cannot be anything else.
Crab and lynx spiders hold their two front pairs of legs open sideways and sit still on flowers. A green spider on a flower in the southern US is a green lynx; a white or yellow one that seems to be part of the petal is a crab spider.
Fishing spiders are the very large flat mottled spiders on tree trunks, boathouses and basement walls near water. They are the animal most often reported as a tarantula east of the Mississippi.
Ground spiders like the parson spider are flat, velvety, and run in short erratic bursts across a wall at night, which is why they get noticed at all.
Why there is suddenly a big spider in the bathtub
Almost every autumn spider question has the same answer: adult males of the large house-dwelling species mature in late summer and abandon their webs to find females. They wander at night, fall into baths and sinks, and cannot climb back out because the enamel gives no grip. They are not coming in for water and they did not come up the drain — a U-bend full of water is not a route.
Two other seasonal patterns are worth knowing. Orb weavers reach full size in late summer, which is why the garden spider that has been there since June suddenly seems enormous in September. And male tarantulas in the southern Plains march across roads in September and October in numbers that make the local news every year.
If you want fewer spiders indoors, the levers are the ones that reduce insects: replace white porch bulbs with warm or yellow ones so the light attracts fewer moths, seal gaps around doors and utility penetrations, and clear the leaf litter and woodpiles stacked against the wall. Spraying pesticide around a foundation is largely theatre against spiders, which walk on the tips of their legs and pick up very little residue.
Moving one out without hurting either of you
The glass-and-card method works on everything in this key. Put a glass over the spider, slide a stiff card underneath, lift, carry, release outside — or in a garage or shed if it is a species that will not survive outdoors in winter. Do not use a vacuum on a spider you want to identify; it destroys the specimen and the legs come off.
Two exceptions. Do not handle a widow or a suspected recluse: use the glass without letting it touch your hand, or leave it and use a sticky trap in the corner instead. And do not handle a tarantula with bare hands — not for the bite, but because it kicks urticating hairs off its abdomen, which sting skin and can cause lasting eye injury.
If you want the identification confirmed, photograph before you release: one shot from directly above showing the whole body and leg markings, and one of the underside through the glass, because for widows the diagnostic marking is on the belly. If you can see the eyes, a close-up of the eye arrangement is the single most useful picture in the whole of spider identification.
The limits of this key
31 entries covering the spiders people actually encounter in and around North American homes and gardens. That is a fraction of one percent of the described fauna, and many genera here — Araneus, Dolomedes, Phidippus, Agelenopsis — contain dozens of species that cannot be separated without examining genitalia under a microscope. Where that is the case the entry names the genus and says what it looks like, rather than pretending to a species.
Regional gaps are deliberate: desert species, cave species, the whole of the tropical Florida fauna and most of the small ground-dwelling families are absent. If an identification matters, post the photograph to BugGuide or iNaturalist with your location and the date; both have arachnologists who identify submissions for free and will tell you plainly when a photograph cannot be taken past genus.
What the observation record shows
Every entry in this key that carries a scientific name is matched against GBIF, the international register of biodiversity records, and against iNaturalist. That puts a hard number behind 31 of the 31spiders here: 1,059,084 georeferenced records across the 27 entries that resolve to a single species, spanning 17 families, the oldest of them collected in 1957. The snapshot was taken on 2026-09-04.
That evidence is not spread evenly, and it is worth knowing before you trust a narrow result. The five best-recorded spiders in this key hold 57% of all the records between them: Cross orbweaver alone accounts for 252,149, while Yellow sac spider has 803. A common thing is common in the data too, so when a filter narrows to one frequent entry and one rare one, the frequent one is usually the answer — and the record count is the quickest way to see which is which. The same skew applies geographically: 42% of these records come from the United States, so the key describes what is reported there far better than it describes anywhere else.
When these are actually reported
Half of every record for this group falls in July–September. A raw month count measures two things at once — when the organism is about, and when people are outdoors with a camera — and the second effect is large enough to give almost anything a summer peak. The line on the figure divides each month by the baseline for every species in every Orvik key, which answers a different question: relative to when people record anything at all, when are these spiders recorded? Values above 1.0 are the months that belong to this group rather than to the season. On that measure 20 of the 27spiders here peak outside the warm half of the year — Zebra jumping spider, Cellar spider, Golden silk orbweaver among them. Those are the ones a seasonal rule of thumb gets wrong.
Records behind each entry
Sorted by how much evidence exists, not by how likely you are to meet one. The peak month is the effort-adjusted figure, and it is left blank wherever the sample is too thin for the month-to-month wobble to mean anything.
| Entry | Accepted name | Rank | GBIF records | Research-grade | Half fall in | Peak, adjusted | Most reported from |
|---|---|---|---|---|---|---|---|
| Cross orbweaver | Araneus diadematus Clerck, 1757 | species | 252,149 | 165,956 | Aug–Sep | September | the Netherlands |
| Goldenrod crab spider | Misumena vatia | species | 106,811 | 82,641 | Jun–Jul | June | Germany |
| Zebra jumping spider | Salticus scenicus | species | 86,602 | 73,832 | Apr–Jun | March | the Netherlands |
| Bold jumping spider | Phidippus audax | species | 81,735 | 132,457 | Mar–Jun | April | the United States |
| Cellar spider | Pholcus phalangioides | species | 79,360 | 57,473 | May–Aug | January | Belgium |
| Black and yellow garden spider | Argiope aurantia Lucas, 1833 | species | 70,101 | 107,746 | Aug–Sep | August | the United States |
| Golden silk orbweaver | Trichonephila clavipes | species | 43,595 | 66,269 | May–Sep | January | the United States |
| Spiny-backed orbweaver | Gasteracantha cancriformis | species | 34,539 | 51,854 | Jul–Nov | December | the United States |
| Banded garden spider | Argiope trifasciata | species | 32,212 | 44,041 | Sep–Oct | November | the United States |
| Orchard orbweaver | Leucauge venusta | species | 32,131 | 50,714 | May–Jun | June | the United States |
| Dark fishing spider | Dolomedes tenebrosus Hentz, 1844 | species | 27,370 | 49,789 | May–Jul | May | the United States |
| Woodlouse hunter | Dysdera crocata C.L.Koch, 1838 | species | 22,126 | 29,441 | Apr–Jul | February | the United States |
| Marbled orbweaver | Araneus marmoreus Clerck, 1757 | species | 21,879 | 27,915 | Aug–Sep | November | the United States |
| Green lynx spider | Peucetia viridans | species | 21,645 | 35,401 | Jul–Sep | October | the United States |
| Joro spider | Trichonephila clavata | species | 20,077 | 27,699 | Sep–Oct | November | the United States |
| Brown widow | Latrodectus geometricus C.L.Koch, 1841 | species | 19,655 | 31,156 | Jun–Oct | February | the United States |
| Spined micrathena | Micrathena gracilis | species | 16,390 | 24,108 | Jul–Aug | August | the United States |
| Giant house spider | Eratigena atrica | species | 16,252 | 42,470 | Jun–Sep | January | Germany |
| Common house spider | Parasteatoda tepidariorum | species | 15,378 | 33,117 | May–Aug | February | the United States |
| Parson spider | Herpyllus ecclesiasticus Hentz, 1832 | species | 12,787 | 22,168 | Jun–Aug | February | the United States |
| Six-spotted fishing spider | Dolomedes triton | species | 12,771 | 18,927 | Mar–Jun | March | the United States |
| Black widow | Latrodectus mactans | species | 9,532 | 14,735 | Jul–Oct | November | the United States |
| Southern house spider | Kukulcania hibernalis | species | 6,235 | 11,476 | Feb–Jul | January | the United States |
| Brown recluse | Loxosceles reclusa Gertsch & Mulaik, 1940 | species | 6,189 | 9,483 | Apr–Jul | February | the United States |
| Texas brown tarantula | Aphonopelma hentzi | species | 6,118 | 11,314 | Apr–Aug | October | the United States |
| Hobo spider | Eratigena agrestis | species | 4,642 | 4,303 | Jul–Sep | January | the United States |
| Yellow sac spider | Cheiracanthium inclusum | species | 803 | 3,704 | Apr–Aug | December | Brazil |
| Long-jawed orbweaver | Tetragnatha Walckenaer, 1805 | genus | 72,848 | 150,215 | May–Jul | June | the United States |
| Wolf spider | Hogna Simon, 1885 | genus | 29,229 | 56,472 | May–Aug | July | the United States |
| Grass spider | Agelenopsis Giebel, 1869 | genus | 24,831 | 70,004 | Aug–Sep | September | the United States |
| Trapdoor spider | Ummidia Thorell, 1875 | genus | 1,541 | 5,366 | Jun–Jul | June | the United States |
This table is assembled from open data and is free to reuse with a link back to this page. The snapshot behind every Orvik key is published as one downloadable file on the open field data page, with each source's licence terms.
Questions people ask about this
How do I know if it is a brown recluse?
Three things must all be true: six eyes arranged in three pairs, legs that are a uniform colour with no bands or stripes, and an abdomen with no pattern. The violin marking is variable and many harmless spiders have something violin-shaped, so it is the weakest of the four characters. Add the range: verified recluses live roughly between Nebraska and western Ohio and south to Texas and Georgia, and are very rare outside it.
What is the messy web in the corner of my garage?
Almost certainly a common house spider or, in the southern and western US, a widow. Both build irregular three-dimensional tangles. The house spider is dull grey-brown with faint chevrons and brown papery egg sacs; a widow is glossy black with a red hourglass on its underside and smooth white egg sacs, and its silk is noticeably tougher — you can hear it tear.
Is a daddy long-legs the most venomous spider in the world?
No, and the claim is wrong twice over. The name is used for cellar spiders, which are spiders with weak venom of no medical significance, and for harvestmen, which are not spiders at all and have no venom glands. The story has been tested on television and in the literature and fails at every step.
Why are there suddenly big spiders in the house in September?
Males of the large house-dwelling species mature in late summer and leave their webs to find females. They wander at night, fall into baths and sinks, and cannot climb the smooth sides to get out. They did not come up the drain and they are not looking for water. The same seasonality makes garden orb weavers seem to appear overnight — they have been there since spring and have only now reached full size.
Do wolf spiders bite?
They can, if pinned against skin, and it feels like a bee sting with no lasting effect. They have no medically significant venom. Wolf spiders are among the most useful animals in a garden, eating large numbers of pest insects, and a female carrying spiderlings on her back is one of the more remarkable things you can watch in a back yard.
What is the spider with the zigzag in its web?
A black and yellow garden spider, Argiope aurantia, or one of its relatives. The thick zigzag ribbon is called a stabilimentum; its function is still debated, with evidence for both web advertisement to birds that would otherwise fly through it and for attracting insects that respond to ultraviolet. The spider is large, striking and completely harmless.
Should I kill spiders in the house?
There is little reason to. Household spiders eat flies, mosquitoes, clothes moths and each other, and the two dangerous groups are recognisable and avoidable rather than eliminable. If you want fewer of them, address what they are eating: switch porch lights to warm or yellow bulbs, seal gaps around doors and pipes, and clear leaf litter and woodpiles stacked against the wall.
Still not sure? Point a camera at it
A filter narrows spiders down to a shortlist. Orvik reads the photo itself and names the species, with the look-alikes ranked underneath so you can check the call yourself.