What the sources say
Spitting SpiderScytodes thoracica
Every figure, record and mechanism on the Spitting Spider profile was written from a source, and this is the working table behind it: 49 claims checked word for word against these sources. The left column is what the page says. The right column is the source's own words, copied, not paraphrased; a ... marks a cut and[brackets] an insertion. Open any source and check it yourself.
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Source
01
Animal Diversity Web, University of Michigan
Scytodes thoracica. Animal Diversity Web, University of Michigan.
- The page saysA tiny house spider
- The source says
This species is a common house spider of the United States.
- The page saysmales typically run 3.5 to 4 millimeters long, and females grow slightly bigger, at 4 to 5.5 millimeters
- The source says
males typically ranging from 3.5-4 mm in length and females ranging from 4-5.5 mm
- The page sayseach divided into a smaller front chamber that stores venom and a larger back one that holds a sticky mucilage
- The source says
These glands are divided into two parts: a smaller, anterior compartment which stores venom and a larger, posterior compartment which contains a mucilaginous substance
- The page saysThe two mix and are fired through the spider's fused chelicerae, fangs that cannot move separately from each other
- The source says
These spiders produce a gummy substance which is a mix of the two substances and is excreted by their fused chelicerae, which can not be moved separately.
Note: "cannot" restates the source's own "can not be moved separately" - The page saysIn the wild a female can live 2 to 4 years and a male 1.5 to 2
- The source says
males live 1.5-2 years and females live 2-4 years. Females may be preyed upon during their egg-carrying periods, while males often die of hunger and exhaustion while searching for and courting females. Range lifespan Status: wild 1.5 to 4 years
- The page saysthey usually die of hunger, exhaustion, or predation
- The source says
These spiders can mate multiple times and usually die of hunger, exhaustion, or predation.
- The page saysSpitting spiders see poorly, so they hunt by touch, tapping a target with their raised front legs until it sits centered between them
- The source says
extremely poor eyesight and therefore walk around with their front legs ... it orients itself towards the prey and slowly taps its front legs until the prey is centered between them
Note: "so" restates the source's own "and therefore" - The page saysThen they fire
- The source says
It then spits a string of a gluey, venomous substance at the prey
- The page saysthe spider lifts its chelicerae, laying the spray down as 5 to 17 overlapping bands
- The source says
covering it in 5-17 parallel, overlapping bands. The material can travel at a rate of up to 28 m/s and the pattern of the bands is produced as the spider lifts its chelicerae and oscillates its fangs during expulsion.
- The page saysThe spider then quickly closes in and tangles its catch further in the drying glue with its first two pairs of legs
- The source says
The spider then quickly approaches its prey and uses its first and second pairs of legs to further entangle the prey in the drying glue, silk and venom.
- The page saysOnce the glue is dry it bites, injecting venom that liquefies the prey's tissues, which it later sucks up
- The source says
once it is dry, the spider bites its victim, injecting venom to liquify its tissues. It then grooms its first two sets of legs, cleaning any remaining glue, before drawing the prey into its chelicerae using its pedipalps. The spider holds the prey with its third legs and wraps it in silk produced by spinnerets. It then consumes its prey by sucking up the dissolved tissues.
- The page saysSpit First, Bite Second
- The source says
their attacks usually proceed in the following order: tapping of the front legs, spitting, biting, wrapping, and then feeding
- The page saysSpitting spiders are slow movers on their long, thin legs, so they use the same spray defensively against predators instead of trying to flee
- The source says
due to their long, thin legs, are slow moving ... Since spitting spiders are slow moving, they use their spitting apparatus against predators, rather than attempting to flee.
Note: "so" restates the source's "Since" - The page saysIt is common in the eastern United States and also found in Britain, Sweden and other European countries, and specimens have turned up in Japan and Argentina
- The source says
This species is commonly found in the eastern United States, as well as in Britain, Sweden and other European countries. Specimens have also been found in Japan and Argentina.
- The page saysIt is unclear which populations are native and which were introduced
- The source says
It is unclear which populations are native and which are introduced in these regions.
- The page saysA House Guest on Four Continents
- The source says
This species is commonly found in the eastern United States, as well as in Britain, Sweden and other European countries. Specimens have also been found in Japan and Argentina.
Note: eastern US (North America), Britain/Sweden (Europe), Japan (Asia), Argentina (South America) = four continents; "house guest" is ADW's "common house spider" - The page saysOutdoors it lives in temperate forest; indoors it is most often found in dark corners, cellars, cupboards and closets of houses
- The source says
Spitting spiders are found in temperate forests. When associated with humans, they are most commonly found in dark corners, cellars, cupboards, and closets of houses and other buildings.
- The page sayswhere it eats moths, flies, other spiders and household bugs, many of them significantly larger than itself
- The source says
when living indoors, they mostly eat other insects and arthropods, such as moths (Order Lepidoptera), Flies (Order Diptera), other spiders (Order Araneae), and household bugs ( Order Heteroptera ) ... Many of their prey items are significantly larger than these spiders.
- The page saysIn Britain it often eats mosquitoes
- The source says
In Britain, mosquitos (Family Culicidae) are often eaten.
- The page saysMany homeowners pay for pest control to get rid of it
- The source says
Many home-owners invest in pest-control in order to exterminate these spiders.
- The page saysNot Evaluated
- The source says
IUCN Red List Not Evaluated
- The page saysLow
- The source says
this spider is venomous, although its chelicerae, or fangs, are too small to pierce human flesh
- The page saysTemperate forests, and dark corners of houses (cellars, cupboards, closets)
- The source says
Spitting spiders are found in temperate forests. When associated with humans, they are most commonly found in dark corners, cellars, cupboards, and closets of houses and other buildings.
- The page sayscommon in the eastern US, also found in Europe, Japan and Argentina
- The source says
This species is commonly found in the eastern United States, as well as in Britain, Sweden and other European countries. Specimens have also been found in Japan and Argentina.
- The page saysMoths, flies, other spiders and household bugs, many much bigger than itself
- The source says
they mostly eat other insects and arthropods, such as moths (Order Lepidoptera), Flies (Order Diptera), other spiders (Order Araneae), and household bugs ( Order Heteroptera ) ... Many of their prey items are significantly larger than these spiders.
- The page saysthen bites once the glue is dry
- The source says
once it is dry, the spider bites its victim
- The page saysAnimal Diversity Web describes spitting spiders as active nocturnal wanderers, not web-spinners
- The source says
Scytodes are active nocturnal wanderers, not web-spinners
- The page saysIt still makes silk from its spinnerets, though, and wraps its prey in it before feeding
- The source says
The spider holds the prey with its third legs and wraps it in silk produced by spinnerets. It then consumes its prey by sucking up the dissolved tissues.
- The page saysThe spider is venomous, but Animal Diversity Web notes that its chelicerae, or fangs, are too small to pierce human flesh
- The source says
this spider is venomous, although its chelicerae, or fangs, are too small to pierce human flesh
Source
02
Suter & Stratton 2009
Suter & Stratton (2009). Spitting Performance Parameters and Their Biomechanical Implications in the Spitting Spider, Scytodes thoracica. Journal of Insect Science.
- The page saysentangles prey from a distance with a zigzag spray of silk, glue and venom
- The source says
subdue prey by entangling them at a distance with a mixture of silk, glue, and venom
Note: genus statement in the paper's abstract; the zigzag is the paper's 'orderly zigzag pattern' for S. thoracica - The page saysfired at up to 28.8 meters a second
- The source says
Ejection velocities were measured as high as 28.8 m/s.
- The page saysSmall Spider, Oversized Glands
- The source says
the domed cephalothorax containing disproportionately large venom glands and the diminutive chelicerae
Note: "small" is ADW's 3.5 to 5.5 mm; "oversized" is the paper's "disproportionately large" - The page saysdomed cephalothorax, the fused head-and-chest section, holds disproportionately large venom glands
- The source says
the domed cephalothorax containing disproportionately large venom glands and the diminutive chelicerae
- The page saysHigh-speed video has clocked the ejection at up to 28.8 meters a second
- The source says
Using high-speed videography ... Ejection velocities were measured as high as 28.8 m/s.
- The page saysthe fangs oscillate side to side up to 1,700 times a second
- The source says
the fangs oscillated at frequencies up to 1700 Hz (826.3 ± 102.7 Hz)
- The page saysZigzag Spray, Timed in Milliseconds
- The source says
depositing material in an orderly zigzag pattern ( Figure 3 ), all in less than 35 ms (25.2 ± 1.4 ms; Table 1)
- The page saysA full burst typically takes under 30 milliseconds
- The source says
A full scan (5–57 fang cycles, one upsweep of a chelicera) typically occupied less than 30 ms
- The page saysThe spit contracts
- The source says
The “spit” was contractile.
- The page saysIn the two-tenths of a second after ejection, its silk shortens by 40 to 60 percent
- The source says
During the 0.2 s following ejection, silk shortened by 40–60%
- The page saysAimed at the two wires of a force sensor, the contracting spit pulled with a peak force of 0.05 to 0.3 millinewtons
- The source says
When the spider's target was a pair of wires instead of a flat surface, the fibrous spit wrapped around the target and, in the subsequent 0.3 s or so, contracted ( Video 4 ). The contraction exerted a peak aggregate force between 0.05 and 0.3 mN ( Figure 6 ) that was dependent, in part, on the number of strands of fiber connecting the two wires of the force transducer.
- The page saysThe spray is a mixture of silk, glue and venom
- The source says
ejecting from their fangs a mixture of silk, venom, and glue onto potential prey
- The page saysThe scientists who filmed it suggest the prey is held physically, by the silk contracting and the glue sticking, rather than by the venom
- The source says
The literature on the effects of spitting spider spit on their insect prey suggests that the spit, at least in some species, contains venom and that this is responsible for the immobilization of prey ( Millot 1930 ; Nentwig 1985 ). This assertion is contradicted by the recent work of Clements and Li ( 2005 ) in which the spit was found to have no toxic effects on prey when applied externally. Our findings suggest an alternative model for the immobilization of prey: the contractile silken component of the spit, either through a drying process or via some other biophysical mechanism, when combined with the adhesive properties of the liquid in the spit, immobilize the prey item through contraction and adhesion.
Note: "rather than" is the paper's "alternative model" to the venom model it cites - The page saysan earlier study found the spit had no toxic effect on prey when applied externally
- The source says
This assertion is contradicted by the recent work of Clements and Li ( 2005 ) in which the spit was found to have no toxic effects on prey when applied externally.
- The page saysFires a zigzag spray of silk, glue and venom at up to 28.8 meters a second
- The source says
Ejection velocities were measured as high as 28.8 m/s.
- The page saysFangs swinging side to side up to 1,700 times a second
- The source says
the fangs oscillated at frequencies up to 1700 Hz
Note: vibe.reason - The page sayslay the spit down in an orderly zigzag
- The source says
depositing material in an orderly zigzag pattern
Note: vibe.reason - The page saysa whole burst usually over in under 30 milliseconds
- The source says
A full scan (5–57 fang cycles, one upsweep of a chelicera) typically occupied less than 30 ms
Note: vibe.reason
Source
03
Ariki et al. 2016
Ariki et al. (2016). Characterization of Three Venom Peptides from the Spitting Spider Scytodes thoracica. PLOS ONE.
- The page saysResearchers have solved the three-dimensional structures of three of its venom peptides, each built around a cystine knot, a motif common to many venom peptides, but could not identify what they target
- The source says
We present the solution-state NMR structures ... of three venom peptides identified from the spitting spider Scytodes thoracica ... structural characterization reveals that these peptides contain an inhibitor cystine knot motif common to many venom peptides ... we have not been able to determine the target of these Scytodes peptides so we can only state with certainty the channels and receptors that they do not target
- The page saysInjected into crickets and blowflies at the doses tested, the peptides caused no paralysis or death
- The source says
Injection of high doses of U 3 -Sth1a (350 nmol/g) and U 5 -Sth1a (310 nmol/g) into sheep blowflies did not cause any paralytic or lethal activity. Likewise, injection of doses of up to 6 nmol/g (U 3 -Sth1a and U 3 -Sth1h) and 12 nmol/g (U 5 -Sth1a) into crickets did not cause any paralytic or lethal activity.
Note: "at the doses tested" carries the paper's dose limits
How the table was made: a writer drafted the profile from these sources and logged each claim with its quote, a reviewer with nothing but this table checked every sentence said no more than its quote, and a script confirmed each quote appears word for word in the source. The method is in the site'sAbout page.