Warmhouse giant crab spider

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Warmhouse giant crab spider
Warmhouse giant crab spider (Heteropoda venatoria), female

Warmhouse giant crab spider ( Heteropoda venatoria ), female

Systematics
Subordination : Real spiders (Araneomorphae)
Partial order : Entelegynae
Superfamily : Sparassoidea
Family : Giant crab spiders (Sparassidae)
Genre : Real giant crab spiders ( Heteropoda )
Type : Warmhouse giant crab spider
Scientific name
Heteropoda venatoria
( Linnaeus , 1767)

The Warmhaus giant crab spider ( Heteropoda venatoria ), often simply called giant crab spider , is a spider from the giant crab spider family (Sparassidae) of the same name . The spider species, which is very large with a leg span of up to 120 millimeters, probably comes from the tropical areas of Asia , but has now spread worldwide. In geographical areas that are actually hostile to survival, the warm house giant crab spider prefers heated buildings in human settlement areas and in particular warm houses , a fact from which the first part of the name can be traced back.

Because the warm house giant crab spider sometimes lives in banana plantations and can therefore be found on traded bananas, it is also known as the " banana spider ". It has this trivial name in common with some species of the genus Cupiennius from the family of fishing spiders (Trechaleidae) and also with representatives of the genus Phoneutria within the family of comb spiders (Ctenidae), which also live on banana plantations. In contrast to the latter, which also includes the poisonous Brazilian wandering spider ( P. nigriventer ), the warm house giant crab spider is largely harmless to humans.

Like all members of the giant crab spider family, the nocturnal warm-house giant crab spider does not create a spider web for catching purposes, but hunts prey freely as a lurking hunter . Because of its considerable dimensions for spiders, the warm-house giant crab spider has a comparatively large range of prey, including larger and more defensive arthropods and smaller vertebrates . Another special property of the species is the male's ability to generate sounds by rubbing two parts of the body ( stridulation ), which is used in courtship .

features

male

The female of the giant crab spider reaches a body length of 17 to 34 millimeters, the male one of up to 21 millimeters. Adult specimens of the species reach a leg span of around 70 to 120 millimeters, which makes the warmhouse giant crab spider a comparatively large spider.

Females at night. The illuminated and therefore reflective eyes are clearly visible.

The physique of the species corresponds to that of other representatives of the real giant crab spiders ( Heteropoda ), which means that the warm house giant crab spider also has a clearly flattened habit (external appearance) that is common for giant crab spiders (Sparassidae) . Likewise, the leg arrangement resembles that of other giant crab spiders, i.e. that is, the second pair of legs is significantly longer. Both rows of eyes are curved backwards and the anterior median eyes are smaller than the anterior lateral eyes. The rear side eyes are on slight elevations. Similar to wolf spiders (Lycosidae), well camouflaged individuals of the warm house giant crab spider are also exposed to a suitable light source at night, e.g. B. a flashlight, easy to find through the reflective eyes.

The basic color of the warm house giant crab spider is brown. Both sexes have a yellow to cream-colored Clypeus (range zw. Eyes and Cheliceren or jaw clutches), and a wide border band that the carapace (back plate of the Prosomas surrounds and front body) which is differently colored in both sexes. In addition, both the male and the female have black spots on their legs, from which a conspicuous and short falling hair originates.

Sense of sight

A closer shot of a female with the eyes that are clearly visible here
Graphic to illustrate the visual sense of the great wandering spider ( Cupiennius salei ), which functions similarly to that of the warm house giant crab spider.

As usual for giant crab spiders (Sparassidae), the warm-house giant crab spider has good eyesight. Here parallels exist to the good vision of the family of fishermen spiders counting (Trechaleidae) Great wandering spider ( Cupiennius salei ). This lives a similar way of life as the warm house giant crab spider, but its eye position is significantly different. Compared to the latter species, however, the great wandering spider has also been researched much better in terms of its visual field of vision.

In 2012, the eyesight of the warm house giant crab spider was researched in two series of experiments. For this purpose, one specimen of the species was placed in a running arena one after the other per experiment. With the help of the first series of tests, two black paper rectangles of different widths were set up in the arena, which the spider should visually perceive as a shelter. The aim was to analyze whether the giant crab spider displayed a visually controlled behavior. The test animal often preferred the wider rectangle over the narrower one and, in many experiments, used the different rectangles to head for it. The probability that the rectangle was tarnished decreased the narrower it became. In further experiments in this series, where two similarly sized paper rectangles were set up, both were approached with about the same frequency. The result of the study is that the eyes of the warm house giant crab spider have a spatial resolution of at least 4 ° to 8 °.

The second series of experiments was used to determine the visual sense of the warm house giant crab spider in connection with its tracks. This species was approached directly and in a straight line, which distinguishes it in this respect from the great wandering spider, which approaches such objects in a sideways zigzag course. It is assumed that this behavior is used in this type to better distinguish different distances between different optically perceived objects. Since the warmhouse giant crab spider does not exhibit this behavior, it is assumed that it visually perceives distances deviating from the large wandering spider or not at all.

Sexual dimorphism

Females (above) and males ventrally compared

As with many other spiders, there is also a considerable sexual dimorphism (difference between the sexes) in the warm-house giant crab spider , which is noticeable in both body size and body structure and coloration of females and males.

female

The female of the warm house giant crab spider is built much stronger and has proportionally shorter legs than the male. In particular, the opisthosoma (abdomen) appears much more powerful than in the male. The marginal band on the carapace is dark yellow in the female. Otherwise, the female is drawn with little contrast compared to the male.

  • Dorsal view of a female

  • Frontal view of a female

  • Lateral view of a female

  • Rear view of a female with a captured frog

  • Carapace of a female with prey

male

The less powerfully built male has longer legs than its female counterpart. Here the marginal band of the carapace appears cream-colored. In contrast to the female, the male also has a dark longitudinal band on the opisthosoma and a light-rimmed and pale area behind the eyes.

  • Dorsal view of a male

  • Frontal view of a male

  • Lateral view of a male

  • Rear view of a male

  • Detailed view of a male with a captured cicada

Genital morphological features

The male of the warm house giant crab spider can be distinguished from all other species of the real giant crab spider ( Heteropoda ) by the two tooth-like appendages. These are located on the retrolateral (further away from the middle of the body) apophysis ( chitinized process) typical of the genus on each of the two bulbi (male genital organs). Another unique selling point of the Warmhaus giant crab spiders is the course of the spermophores (seed tubes) in each of the two bulbs: A single spermophore has a large, rectangular area in the distal (laterally facing away from the body) half of the tegulum (second sclerite or limb of the globe) curve-like course.

The epigyne (female sexual organ) of the Warmhaus giant crab spider has a lobule on each side, which both touch on the median plane and expose anterior (anterior) and posterior (posterior) parts of the septum.

  • A closer shot of a male with the easily visible bulbs

  • Anterior view of a female with clearly visible epigyne

Similar species

The warm house giant crab spider is occasionally confused with other visually similar spider species. Examples are given in the following two subsections.

Similarities to Heteropoda tetrica

Females of Heteropoda tétrica

Within the genus of the real giant crab spider ( Heteropoda ), the warm-house giant crab spider can be confused with the species Heteropoda tetrica, which is widespread in Indochina . The male of this species, however, has two parallel stripes in front of the band in addition to the edge band. The females of both species can usually only be reliably differentiated by characteristics of the very similarly structured epigynes. In the female of H. tetrica , the middle septum has a greater variability than in the warmhouse giant crab spider.

Confusion with Loxosceles reclusa

The similar and for humans much more dangerous spider species Loxosceles reclusa .

The warm-house giant crab spider is occasionally confused in the United States with the not closely related spider species Loxosceles reclusa from the family of the six-eyed sand spiders (Sicariidae). Compared to the warm house giant crab spider, the bite of Loxosceles reclusa can cause symptoms that are more medically relevant for humans.

Happen

Female in Okinawa, Japan

The warmhouse giant crab spider was originally believed to be native to Southeast Asia and has been introduced to many parts of the world including Europe , Africa , America , the Pacific Islands, and Macaronesia . In areas that do not allow the species to survive in the wild due to seasonal fluctuations, including Central Europe , it occurs synanthropically (bound to human settlement areas).

Habitats

Males in a botanical plant in the Chinese province of Yunnan

No more detailed information is available about the preferred habitats of the warm-house giant crab spider in their original range. In climatically unfavorable areas, the species introduced there can be found particularly in heated facilities, including above all greenhouses and heated warehouses . From the US state Florida , however, there are also reports of an adaptation outside of human dwellings, where the warm-house giant crab spider lives in particular in avocado groves.

Preference for banana plants

Dessert banana plantation ( Musa × paradisiaca ) in Tayap ( Cameroon )

Together with species of the genus Cupiennius from the family of fishing spiders (Trechaleidae) and species of the genus Phoneutria from the family of crested spiders (Ctenidae), the warm-house giant crab spider is also known as the "banana spider". The name is derived from their preference for the dessert banana plant ( Musa × paradisiaca ), with females being found far more frequently than males on corresponding plantations.

The preference for banana plantations can be explained by the fact that the plants of the dessert banana not only offer food for prey during the day, but also many retreats for the nocturnal spiders. Depending on its age, the spider uses different cavities on the pseudostems, the bracts and the fruiting bodies. The upper area with the foliage and fruits is preferred to the lower area of ​​the banana plants. Adult animals, especially females with egg cocoons , usually seek refuge under the loose leaf sheaths and the spaces between the fruiting bodies and stands. Young animals, on the other hand, can also be found in the grooves on the leaf-sheath stalks and under the bracts. This preference for higher plant parts can be explained by the presence of predators in the lower area of ​​the banana tree.

The rate of find in the respective areas of the banana plant varies over time, as could be observed in Cameroon , for example . Between April and August, specimens of the warm-house giant crab spider were found mainly in the spaces under the loose leaf sheaths around the pseudostems and in grooves on the leaves or stems of the banana plants. Between September and March, d. H. When the banana plants are in bloom, the spiders stay in the grooves of the stems of the leaf sheaths and between the bracts and the fruits in the upper part of the plant.

way of life

Active female at night

The warm house giant crab spider is primarily nocturnal. During the day she hides in temporary shelters. Due to the flattened physique of the spider, these can also be narrow cracks.

Hunting behavior

Female with a captured cricket

Like almost all spiders, the Warmhaus giant crab spider lives exclusively predatory , hunts like other giant crab spiders (Sparassidae) without a safety net and consequently hunts prey freely. Like all giant crab spiders, it can run at high speeds.

Capture and track down prey

How exactly the warm house giant crab spider catches its prey has not yet been conclusively clarified. According to an observation-based theory from China , the spider is a stalker ; That is, it waits for prey, which are then overwhelmed with the help of a quickly executed venom bite . It is also believed that the species is also actively searching for prey, as is the case with other giant crab spiders. If there are flying insects within reach, they can be jumped at. The prey is presumably registered and located beforehand by means of the lyre-shaped organs , i. H. the organs of perception for sound vibrations typical of spiders.

Range of prey

Especially cockroaches like here z. B. Blattella asahinai make up a large part of the prey of the warm-house giant crab spider.

The warm house giant crab spider is an opportunistic hunter and consequently hunts all prey that the spider is able to overwhelm. Other arthropods are most commonly captured. Tests carried out in 2013 showed that the warm-house giant crab spider prey on a wide variety of insects such as cockroaches , grasshoppers , houseflies , mosquitoes , lice , dragonflies and ladybugs . Only smaller individuals of the species with a body length of up to 15 millimeters captured flies, mosquitoes and lice, which were mostly ignored by the larger spiders. Ants were completely avoided in the test series. Also other spiders like real orb web spiders (Araneidae) from the genera of the reed cross spiders ( Neoscona ) and the southern orb web spiders ( Argiope ), trembling spiders (Pholcidae) from the genus of the mosquito ( Crossopriza ) and the real trembling spiders ( Pholcus ), jumping spiders (Salticidae) from the genus Plexippus and ball spiders (Theridiidae) from the genus of the real ball spiders ( Theridion ) accepted the specimens of the warm house giant crab spider as prey under laboratory conditions. Here, however, cockroaches in particular and, secondly, mosquito trembling spiders turned out to be the preferred prey of the giant crab spider.

Smaller vertebrates such as the Asian house gecko ( Hemidactylus frenatus ) expand the range of prey for the species.

The species has also been observed overpowering defensive prey such as scorpions or small vertebrates such as bats . In 2017, a female of the warm-house giant crab spider was observed eating a specimen of the Asian house gecko ( Hemidactylus frenatus ), which was also adapted to human settlement areas and which had already overwhelmed it at the time of sighting and which had already been half drained. The spider measured a body length of 23 and a leg span of 110 millimeters. The find took place in the village of Jaymoni in the district of Bagerhat in southwest Bangladesh. The site was a wooden column.

Attracting nocturnal prey

Females at night with the clearly visible stripe of the face between the eyes and the chelicerae

The light edge band on the carapace of the warm house giant crab spider is frontally designed as a clear stripe, which is used to lure nocturnal and airworthy insects with good eyesight, including moths and some bees , to the spider. This strip reflects light in the range from 300 to 700 nanometers. However, it has not yet been clarified exactly how the strip attracts the respective prey.

Similar phenomena are also known from other spiders, such as Nephila pilipes from the family of silk spiders (Nephilidae), which has yellow ventral stripes on the opisthosoma that have the same function. Further examples that show such colorations on the Opisthosoma are the spider species Leucauge magnifica (yellow ventral stripes ) from the family of the extensor spiders (Tetragnathidae), Neoscona punctigera (paired ventral points) and Argyrodes fissifrons (silvery points) from the family of crested web spiders (Theridiidae) . In contrast to the warm house giant crab spider, however, these species all create wheel nets to catch prey, so that the prey animals are then lured into their nets. The warm-house giant crab spider, which does not create a spider web for catching purposes, then prey on the animals as soon as they come within range.

There is also the assumption that the light stripe of the warm house giant crab spider also serves to deter nocturnal predators with good visibility, such as geckos , which has already been reported in N. pilipes . A third function of the strip that is suspected is the nightly spotting of sexual partners. This assumption stems from the good eyesight of the warm house giant crab spider, which is also well adapted to the darkness of other nocturnal free-roaming spiders, such as the great wandering spider ( Cupiennius salei ). It is also known that striped drawings in the facial region of jumping spiders (Salticidae) have a great influence on their choice of mate.

Life cycle and phenology

The life cycle of the warm house giant crab spider, like other spiders, is divided into several sections. The reproductive behavior and the growing up of the young animals was especially documented in captivity.

The phenology (activity time) of the warm house giant crab spider covers the whole year. The same applies to the development time, so that adult specimens and young animals can be found simultaneously at any time of the year. The mating season is not limited to a specific time period either.

Creation of the sperm network

As with other spiders, a sexually mature male of the warm-house giant crab spider creates a so-called sperm web and takes in the previously released sperm through his bulb before it seeks out a female. The bulbi are cleaned by the male for five to 25 seconds after ingesting the sperm.

Courtship

If a female has been found, the male begins with his remarkable courtship behavior , which, in addition to optical signals, together with a few other spiders, including the fat spider ( Steatoda bipunctata ) or some jumping spiders ( Salticidae) or tarantulas (Theraphosidae), sometimes stridulations (sound generated by rubbing two body parts). First, however, the male carefully approaches the female, holding his first pair of legs raised and stretched forwards. Then she rubs those legs together on either side while the female remains immobile.

Optical stimuli
Male illuminated at night with a missing leg and the here clearly visible horizontal stripe between the eyes and the chelicerae

The courtship behavior of the warmhouse giant crab spider is influenced, among other things, by the female's perception of optical properties, including the size of the male. A larger male is more likely to be adopted as a mate by a female than a smaller one. It is believed that this is related to the fact that a smaller male is more likely to escape or be less noticeable by a female. A third possibility would be that a larger male can also have a larger frontal stripe, which, in addition to its function as a lure for prey and a repellent against predators, plays an important role in the choice of mate.

A better fed male will have a larger streak than one who has eaten less food. It is therefore assumed that females of the warm-house giant crab spider can differentiate between males with a more covered nutritional requirement and those with less, who are then ultimately less preferred. However, it is so far unclear whether the species can distinguish between chromatic and achromatic color patterns. Some nocturnal spiders, such as many tarantulas (Tharaphosidae), have conspicuous setae (chitinized hair ), which is why it is assumed that the color patterns of these spiders play an important role in mating. In contrast, the closely related and contrastingly colored great wandering spider ( Cupiennius salei ) seems to be color-blind.

Stridulation
The male probably performs the stridulation with the two rear pairs of legs

The stridulation forms the second elementary component of the courtship of the warm house giant crab spider. For the Stridulation the male spreads all four pairs of legs, pinned all thereon Tarsen (heel elements) to the ground and lifts the body slightly. In contrast to the other spiders capable of stridulation, the male of the warm house giant crab spider does not generate these noises by means of the pedipalps , but presumably mainly through the two rear pairs of legs. However, there are no stridulation organs developed morphologically significantly different from those of the other species. During stridulation, in addition to the two pairs of legs involved, the fourth and the last, minor vibrations can also be detected along the opisthosoma. The frequencies of the vibrations of the legs of a courting male of the warm house giant crab spider measured in 1980 were 63, 83 and 125 Hertz , with the fourth pair of legs exhibiting the highest of the frequencies determined. However, studies suggest that only the leg movements, and especially those of the fourth pair of legs, are decisive for the generation of noises and that the vibrations of the opisthosoma are merely passive vibrations induced by the leg movements. The noise resulting from the vibrations of the fourth pair of legs is a hum that is also weakly perceptible to the human ear, which can be heard up to 30 centimeters away and sounds at different distances within four sections of different tones.

First, several closely spaced wave trains sound, the rate of which gradually increases and their duration is around 25 seconds in total (a single wave train lasts around two and a half to four seconds). This is followed by a two-part humming tone as the "primary section", which sounds first in tone A and after a while in tone B. The frequency here is significantly higher and more homogeneous than in the previous wave trains, although the second part of this section can also have a higher or lower frequency than the first. In the third section, the acoustic signal is almost completely suspended for a short time and is instead probably replaced by an exploratory behavior lasting 30 seconds. The fourth and last section then form several low-frequency wave trains, similar to the first. Following on from the last section, the first can be started again and the courtship behavior is repeated.

pairing

pairing

If the female is willing to mate and therefore a mating takes place, the male drums with his pedipalps on the ground and makes vibrating movements before slowly climbing the female head-on. As a result, both sexual partners take the position that is typical for real spiders who hunt without a safety net, in which they look in the opposite direction. Immediately before mating, the male encloses the female's prosoma with the two rear pairs of legs.

The actual mating can take up to six hours and the male strokes the ventral side of the female with his pedipalps when importing an eyeball for the first time. During mating, the male permanently changes his bulbs to be inserted into the female's spermathec at an interval of an average of 20.4 seconds, a maximum of one minute. A single insertion of the respective globe takes six to seven seconds. To achieve this, the male tilts his prosoma either to the right or to the left side, lifts the opisthosoma of his partner with the front pair of legs so that the insertion can take place with the eyeball lying on the tilted side.

After mating, the mostly exhausted female often forcibly frees herself from the male's grip and cannibalism on the part of the female towards her sexual partner is not uncommon . The mostly higher find rate of female individuals of the warmhouse giant crab spider compared to males could be explained in this way.

Making cocoons and laying eggs

Female with a fresh egg cocoon

About 10 to 15 days after mating, the opisthosoma of the pregnant female begins to swell significantly as a result of the eggs maturing in it. The production of the egg cocoon occurs around 28 to 30 days after mating. This is round in shape, laterally flattened and has a diameter of 12.7 to 25.4 millimeters and a height of 3.18 to 6.35 millimeters. In various examinations, 188 to 436 eggs or an average of 163 and a maximum of 400 eggs were counted in the cocoon. These have a diameter of 1.5 millimeters. At first the cocoon is still creamy white.

To construct the cocoon, the female leans forward and assumes a somewhat C-shaped posture. It then produces threads of spider silk from its spinnerets and lays them on the ground to form a spherical flat disc with a diameter of around 20 millimeters. This process usually takes about 20 minutes. The spider then moves repeatedly around the perimeter of this disc, depositing more silk strands each time on the outermost strand, until the spherical disc has assumed a saucer-shaped structure with a height of about one millimeter. After that, she walks around the silk structure and then sits down on it for about two minutes to lay her eggs. During the egg-laying process, the female's opisthosoma slowly but visibly loses volume. After laying the eggs, the female assumes the C-shaped body position again and devotes herself to the completion of the cocoon by again circling the silk construct around its axis in order to lay further silk strands and thus seal the cocoon from above.

Incubation

Partially hidden female with an older egg cocoon

After making the cocoon, the female presses it under her to her opisthosoma for about two minutes before separating the cocoon from the ground with the help of her pedipalps. The cocoon is kept close to the sternum (breast shield of the prosoma) by the female during the entire incubation period with the help of the chelicerae and the pedipalps . The initially light cocoon gradually darkens and also shrinks slightly over time. The female carries the cocoon with her continuously until hatching, which takes place around 30 days after egg-laying, and does not eat any food during this time. Because of this, starvation of the female can result or the cocoon can be eaten up by the female. Cocoons with unfertilized eggs are either dropped or eaten by their manufacturers. In this case, the incubation is interrupted and thus the hatching of the young animals is easily prevented.

A mated female can produce a maximum of three cocoons in succession. However, as the number of cocoons created by a female increases, the hatching rate decreases and can drop below a third of the maximum hatching rate of the first cocoon. The time interval between the successive egg cocoons is around 50 to 60 days. It is also possible to give a female of the warm house giant crab spider a cocoon previously made by another, which she then accepts and treats like her own. In this case, the hatchlings will also hatch after the incubation has been successfully completed.

Slip

Females with an egg cocoon, whose offspring are about to leave the cocoon. The young animals are already clearly visible through the holes in the cocoon.
Picture of a slip of young animals from the book The biology of spiders of Theodore Horace Savory (1928)

The young spiders hatch after about eight to 14 days in the form of pre-larvae and go through two stages in this form. In the first, the chorion of the egg is largely repelled and remains at the rear end of the prelarve as a crumpled-looking mass. The first stage lasts one to six days. In the second, the vitelline membrane (yolk skin) is completely shed. After about five or six days after the start of this stage, the eye pigments appear and shortly afterwards the drawing elements and the setes typical of the species appear. The pre-larvae remain in this stage for up to ten days before they molt for the first time and are thus in the larval stage. These two processes still take place in the egg cocoon

About 28 days after the eggs are laid, several tiny holes become visible on the shell of the egg cocoon, which now takes on a gray hue shortly before the young animals hatch. At regular intervals, the female enlarges these holes with her legs. After a further 29 to 40 days (on average about 32), the young spiders now leave the egg cocoon, whereby the incubation can fail with some eggs and thus they do not hatch. Hatched young animals first gather on the shell of the now empty egg cocoon, which is still held by the female and into which they retreat in the event of disturbances. The young animals become independent by producing silk strands at this point and using them to abseil from the cocoon. The female holds the empty egg cocoon for about 10 days after hatching, until it finally drops. As a result, its need for food has risen sharply due to the previous phases of development and it tries to kill a large number of prey for this purpose.

Development of the young animals

Cub

As with arthropods usual, the young hot house giant crab spider overgrown molting approach and go through it several feeding skins (molting stages of spiders). Males go through a total of nine moults and females twelve. As a rule, these young spiders molt once a month. One or two days before molting, a young animal stops eating, takes on a darker color and immediately before molting begins to hang upside down on a spider thread and then pulls its legs together. The moult takes place at night and takes about 30 minutes. A skinned young animal resumes feeding about five days after molting.

Molting a male

After each moult, the different parts of the body increase in size differently. Especially in growing males, the elongation of the legs after a molt is usually higher than in females. The sexual dimorphism becomes particularly evident from the seventh molt. The attachment of the bulbi is more visible in males and the legs are significantly longer compared to those of females at this stage. In spiders that have reached the adult stage under laboratory conditions, the prosoma takes on a length of 5.6 millimeters. A deviation of 0.3 millimeters can occur. After moulting, the opisthosoma becomes 5.8 millimeters long with a deviation of 0.5 millimeters. After moulting, the four pairs of legs reach a total length of 47.1 millimeters with a deviation of 3.1 millimeters. The pedipalps are 4.9 millimeters long at the end, although here, too, there may be a deviation of 0.5 millimeters in this case.

During a moult, parts of the limbs can get stuck in the old exoskeleton ( chitinized support structure) and, after separation, fuse with the stripped exuvia (discarded exoskeleton after a moult). In the subsequent molting, the missing extremities are replaced, but they are smaller afterwards. With each subsequent molt, however, these limbs grow to the size of the original. Only fully grown spiders can no longer regenerate lost extremities, as they no longer shed their skin after the last moult, the so-called maturity moult, after which sexual maturity occurs.

Duration of adolescence and life expectancy

Young male with a regrown leg

The males need less time to grow up because they moult less, with 304.7 days and a possible deviation of 12 days, somewhat less time than the females, whose development is 391.6 days with a possible deviation of 2.9 amounts to.

Under laboratory conditions, males achieve a total lifespan (including the embryonic stage) of 355 to 586 and females of 298 to 710 days. The survival rate under these conditions is 85%.

toxicology

The poison of the warm house giant crab spider consists of low molecular weight substances and salts, as well as peptides and proteins. The latter partly act as spider toxins , the nature and effect of which is being researched with the help of toxicology .

Composition of the poison

toxin Mass (Da) amino acids EC 50 (Kv4.2)
HpTx1 3910.57 33 100 nM
HpTx2 3412.72 30th 100 nM
HpTx3 3599.38 31 67 nM

The poison of the warm house giant crab spider is described as a clear, colorless liquid that can be easily dissolved in water. It is fatal to cockroaches with an LD 50 value of 28.18 μg / g. Its density is 978 mg / ml, the protein content is about 32%. The proteins include over 100 peptides, the majority of which are in a molecular weight range of 3000 to 5000 Da, which corresponds to 27 to 40 amino acids. The three heteropodatoxins (HpTx) and the insecticide μ-Sparatoxin-Hv2 are also in this weight range. Based on the peptide sequence and the position of the cysteine units, 154 peptide precursors from spider venom can be divided into 24 families.

The heteropodatoxins are inhibitors for voltage-activated potassium channels with masses of 3.4 kDa to 4 kDa. They consist of 30–33 amino acids with an amidated C-terminus and have a sequence identity of 39–41% with one another. The six cysteine ​​units that determine the tertiary structure are in similar positions and form three disulfide bridges. In addition, the HpTx3 has 39% in common with the Hanatoxin 2 (HaTx 2 ) found in Grammostola rosea . The HpTx block the Kv4.2 channels in a voltage-dependent manner, which leads to a prolonged action potential .

The μ-Sparatoxin-Hv2 is mainly insecticidal. The toxin acts on the Na v s channels of cockroach cells with an IC 50 of 6.25 μg / ml or 833.7 nM, while it has no effect on potassium and calcium channels. The toxin has a weaker effect on rat cells and only partially blocks the channels, while it has no effect on mice at a dose of 7.0 μg / g.

The peptides as an indicator for the evolutionary development of spider toxins

The evolution of cysteine- rich peptides between the tarantula-like (Mygalomorphae) and the real spider (Araneomorphae) can be illustrated using the warm house giant crab spider . Like all of the giant crab spiders, the species is one of the comparatively more primitively built real spiders. The phylogenetic relationships between the spider families show that the warm-house giant crab spider, like other giant crab spiders, is phylogenetically located between the more primitive tarantulas (Theraphosidae) and the more modern wolf spiders (Lycosidae). With these and some other spider families, the giant crab spiders also share the hunting tactics as ambulance hunters who hunt without a spider web and thus stand in contrast to the web -building spiders, which only developed later and whose poisons are more complex and effective.

Cysteine-containing peptides are a further indication that the warm-house giant crab spider is one of the earlier, more recent representatives of the real spider, since the proportion of cysteine ​​in spider toxins has decreased with advancing evolutionary development. The cysteine-rich peptides with six cysteine ​​units each can make up over 69% of the total protein in tarantulas such as the black ( Cyriopagopus hainanus ) and the blue tiger tarantula ( C. schmidti ) as well as the tarantula species Grammostola rosea and Chilobrachys jingzhao . In the warm house giant crab spider, 55% of the toxin protein, while the poison peptides of the Araneus ventricosus species , which belongs to the cross spiders ( Araneus ), only 10% consists of cysteine-rich peptides with six cysteine ​​bonds. Some spider species, including the predatory spider species Dolomedes mizhoanus , which, like the warmhouse giant crab spider, hunts without a safety net, and the South Russian tarantula ( Lycosa singoriensis ), which belongs to the wolf spiders , do not have any of these proteins in their toxins.

Identification and nomenclature

A full-length precursor of the cysteine-rich peptides contains a signal sequence and a mature peptide, while some precursors of the cysteine-rich peptides additionally contain a precursor protein before the mature toxin sequence, which is also the case for the precursors of the vast majority of the previously reported peptides Spider toxins applies. The alignment of the resulting amino acid sequences resulted in an extensive variation in the molecular structure of the transcripts for most of the occurring forms of the cysteine-rich peptides.

Systematics

In the field of biology, the systematics deals with the taxonomic (systematic) classification as well as with the determination (biology) and with the nomenclature (discipline of scientific naming) of living beings, including the warm-house giant crab spider.

The species name venatoria is a modification of the Latin noun venator , which means "hunter".

Description history

The Warmhaus giant crab spider has undergone several changes and renaming since it was first described . First describer Carl von Linné gave the species the name Aranea venatoria in 1767 (at that time all spiders were divided into this genus, which no longer exists today). When Pierre André Latreille described the genus Heteropoda for the first time in 1804 , he also classified the warm-house giant crab spider in the same and it was given the name Heteropoda venatoria , which is still valid today and has been used almost continuously since around 1900. Today the warmhouse giant crab spider is the type species of the genus.

Subspecies

In addition to the nominate form H. v. venatoria two other subspecies that were first described by Tord Tamerlan Teodor Thorell in 1881 . These are the following:

  • H. v. emarginata
  • H. v. foveolata

Synonymized species and subspecies

Under Peter Jäger in 2014, several previous species from the giant crab spider family were synonymous with the warm house giant crab spider and thus lost their species status. One example is the species Ocypete thoracica , discovered by Carl Ludwig Koch in 1845 , which Jäger was able to identify as a warm-house giant crab spider based on Koch's illustration through the drawing of the carapace. In 1878, Tord Tamerlan Teodor Thorell allegedly described a male from the Indonesian island of Ambon . He already mentioned the similarity of this animal to the warmhouse giant crab spider and considered whether it was a subspecies of this.

Carl Ludwig Koch's son Ludwig Carl Christian Koch described two females of the Warmhaus giant crab spider as a new species under the generic name Sarotes , which is no longer used today . One of them, Sarotes aulicus, can be identified as a warm-house giant crab spider using the illustration. The second is Sarotes invictus , which was wrongly determined by Friedrich Wilhelm Bösenberg and Embrik Strand . Strand recognized the error and in a publication published in 1906, three years after Bösenberg's death, assigned the found specimen to the species Heteropoda invicta, which is closely related to the giant crab spider . Ferdinand Karsch made an illustration of a male as early as 1881, which, however, clearly represents one of the Sinopoda forcipata species belonging to the same family . The female holotype of Sarotes invictus, on the other hand, can clearly be assigned to the warm-house giant crab spider, which confirms the synonymisation with the warm-house giant crab spider.

The holotype of the species Sinopoda formicata , first described by Karsch in 1881, also turned out to be a specimen of the warm-house giant crab spider in 2014. This holotype is 27.3 millimeters in length and was initially measured by Karsch to be around 30. This incorrect measurement may result from the fact that spiders stored in ethanol develop a longer petilous (dividing stalk between prosoma and opisthosoma) over time, which Karsch may not have taken into account.

Another species assigned to the genus Sarodes was S. truncus , which was first described by Henry Christopher McCook in 1878 . McCook already mentioned the strong resemblance of S. truncus to the warm-house giant crab spider, which differed from other known individuals of the latter species only in the shape of the prosoma, which is why McCook himself questioned whether S. truncus really is a species of its own . Since the person who first described this questionable species himself emphasizes that all other properties of the specimen he describes correspond to the species-typical of the warmhouse giant crab spider, it is assumed that the prosoma of this specimen was deformed by a false moult and thus the different appearance of the prosoma could be explained .

Strand described the following three subspecies in 1907:

  • Heteropoda venatoria chinesica
  • Heteropoda venatoria japonica
  • Heteropoda venatoria maculipes

At H. v. chinesica and H. v. japonica only differ in the two teeth and the distal edge of the retrolateral tibial abophysis from the nominate form of the warmhouse giant crab spider, which would not be sufficient as a criterion for a separate species or subspecies. At H. v. maculipes Strand mentions a color variation, which, however, could never be confirmed in retrospect.

In 1915, Strand also described the very similar species Heteropoda nicki from Java and the subspecies H. n. Quala from Sumatra , both of which have an epigyne and vulva very similar to the warm-house giant crab spider. Both H. nicki and the subspecies can only be differentiated by the size given by Strand, which is smaller than that usual for the giant crab spider, although similarly small individuals of the latter type are known from the Krakatau archipelago . The same applies to the species Heteropoda tokarensis , first described by Takeo Yaginuma in 1961 , whose illustrations also turned out to be the giant crab spider in 2014.

The species Heteropoda andamanensis was first described by the Andamans in 1977 by Benoy Krishna Tikader , which initially actually showed characteristics of its own through illustrations. These were the hook-shaped dorsal-retrolateral tibial abophysis and the easily visible median septum in the bulbs as well as the very narrow anterior (anterior) width of the prosoma. However, the illustrations were revised by Tikader and Veena D. Sethi in 1988, so that the illustrated specimens from now on have a wider prosoma and an existing but no longer hook-shaped dorsal-retrolateral tibial abophysis. In addition, the side lobes of the epigyne now touch, as is the case with the warm-house giant crab spider. Other properties that H. andamanensis shared with this in the illustrations are the shape and course of the vas deferens and the spermophores, which confirms the synonymisation.

In addition to H. andamanensis, Tikader also described Heteropoda nicobarensis in the same year , which, according to the name , was discovered on the Nicobar Islands . Sethi and Tikader made an illustration of the female holotype including the vulva for the first time in 1988. All illustrations and especially those of the holotype also correspond to the Warmhaus giant crab spider. The species Heteropoda hainanamensis , first described by Ai-Hua Li in 1991, can also be proven as a synonym for the warm-house giant crab spider based on the illustrations of the three female holotypes from the Chinese province of Hainan .

Warmhouse giant crab spider and human

Males in a house on the Thai island of Ko Chang

It is not uncommon for humans to meet the giant crab spider, especially in tropical areas. Because of this, and not least because of its global introduction, the species has a different reputation.

The warm house giant crab spider as a beneficial insect

Females with seized Gender animal a termite found in India .

In the tropical areas in particular, the warm-house giant crab spider is often considered a beneficial insect and a welcome guest in houses, as it decimates a large number of pests such as cockroaches there . The species has also proven useful on banana plantations, where it can significantly minimize pest populations if there is a sufficiently high density of individuals.

Due to the nomadic way of life and the large range of prey, which includes many pests, the warm-house giant crab spider is also considered to be more useful than other, especially web-building spiders. In addition to being infested by cockroaches, flies should also be able to be controlled comparatively easily with the aid of the species. An experiment carried out in buildings in South Africa in 1990 confirmed this assumption when individuals of the warm-house giant crab spider abandoned in the buildings reduced the total populations of the flies found there by 99% within two and a half months. This also reduced the incidence of gastrointestinal infections (affecting the digestive tract) in people in this region, since the flies, as the carriers of these, have been almost completely decimated.

As food

The warm house giant crab spider is one of the edible spiders . A consumption history is scientifically documented for Venezuela .

Terrariums

Due to its impressive appearance for spiders, the warm house giant crab spider is occasionally kept as a pet in the terrarium hobby. The species is considered to be easy to care for due to its robustness and adaptability, but its high speed should be taken into account. There are also offspring in captivity.

Imports through banana fruits and reactions

The Brazilian wandering spider ( Phoneutria nigriventer ), which is much more dangerous for humans and is known as the "banana spider" like the giant crab spider.

As individuals of the warm-house giant crab spider are skillfully able to hide themselves on banana trees due to their physique and often unnoticed , imports of both living and deceased specimens of the warm-house giant crab spider or their exuvia through the import of banana fruits occasionally occur, which are often regarded as unpleasant. This has also given the species the name "banana spider" (translated: "banana spider"). However, it should not be confused with the representatives of the genus Phoneutria from the family of comb spiders (Ctenidae) known under the same name and also clearly more dangerous for humans .

Especially in areas where the warm house giant crab spider is not established, at least in the open air, finds of the species in supermarkets, for example, can cause panic due to their imposing and dangerous appearance for some people. This is reinforced by the fear that these individuals of the species could be much more dangerous and in the past also exported through banana trees, such as those of the Brazilian wandering spider ( Phoneutria nigriventer ). One example is a specimen of the warm house giant crab spider found in a supermarket of the REWE chain in the municipality of Wilhelmsthal in the Upper Franconian district of Kronach , which was later reliably identified as an individual of the species by arachnologists from the Senckenberg Research Institute in Frankfurt am Main .

Bite accidents and symptoms

Due to their size and their strong chelicerae, it is possible for the warm house giant crab spider to penetrate human skin when it bites. However, the species is not aggressive and only bites in extreme distress. This does not apply to pregnant females or those defending their egg cocoons. Otherwise, the giant crab spider's bite accidents can result from individuals of the species being carelessly held, harassed or squeezed.

The symptoms of the bite are considered medically irrelevant. Local pain and occasionally swelling in the area of ​​the bite wound are noted. The pain subsides within a few minutes.

Threat and protection

The IUCN does not record the global populations of the warm house giant crab spider . As a result, there is no information about potential threats to the species and it is also not subject to any protection.

The species is also not rated in the Red List of Endangered Species of Animals, Plants and Fungi in Germany or the Red List and Total Species List of Spiders in Germany (2016), as the warm-house giant crab spider is not native to Germany and is only found in heated facilities anyway. Here the species is considered to be very rare and its populations will increase in the long term.

Individual evidence

  1. ↑ a b c d e f g h i j Heteropoda venatoria (Linnaeus, 1767) from araneae - Spiders of Europe, accessed on January 19, 2020.
  2. ↑ a b c d e f g h i j k l m n o University of Florida : Huntsman Spider, Heteropoda venatoria (Linnaeus) (Arachnida: Araneae: Sparassidae). by Glavis Bernard Edwards Jr., accessed January 19, 2020.
  3. ^ Christian Lorenz: The spider Heteropoda venatoria and its visual system . 2012, p. 7 , doi : 10.25365 / thesis.21679 . , accessed on January 7, 2021.
  4. ^ Christian Lorenz: The spider Heteropoda venatoria and its visual system . 2012, p. 7-8 , doi : 10.25365 / thesis.21679 . , accessed on January 7, 2021.
  5. ^ Christian Lorenz: The spider Heteropoda venatoria and its visual system . 2012, p. 8 , doi : 10.25365 / thesis.21679 . , accessed on January 7, 2021.
  6. ↑ a b c d Peter Jäger: Heteropoda Latreille 1804: new species, synonymies, transfers and records (Araneae: Sparassidae: Heteropodinae). In: Arthropoda Selecta . tape 23 , no. 2 , 2014, p. 153 . , accessed on September 30, 2020.
  7. ↑ Peter Jäger: Rarely proven spider species from Germany (Arachnidae: Araneae). In: Arachnological Messages . tape 19 , no. 1 , June 2000, pp. 53 . , accessed on January 5, 2021. September 24, 2020.
  8. ↑ a b c Heteropoda venatoria (Linnaeus, 1767) in the WSC World Spider Catalog , accessed January 19, 2020.
  9. ↑ Jude A. Ewunken, Nelson N. Ntonifor, Mbua Christophe Parr: BIOECOLOGY OF Heteropoda venatoria (Linnaeus) (Araneae: Sparassidae) AND ITS IMPLICATIONS IN A TROPICAL BANANA AGROECOSYSTEM . In: Journal of Global Agriculture and Ecology . tape 5 , no. 2 , 2016, ISSN  2454-4205 , p. 164 . , accessed on September 24, 2020.
  10. ↑ a b c d e Jude A. Ewunken, Nelson N. Ntonifor, Mbua Christophe Parr: BIOECOLOGY OF Heteropoda venatoria (Linnaeus) (Araneae: Sparassidae) AND ITS IMPLICATIONS IN A TROPICAL BANANA AGROECOSYSTEM . In: Journal of Global Agriculture and Ecology . tape 5 , no. 2 , 2016, ISSN  2454-4205 , p. 169 . , accessed on September 24, 2020.
  11. ↑ a b c Jude A. Ewunken, Nelson N. Ntonifor, Mbua Christophe Parr: BIOECOLOGY OF Heteropoda venatoria (Linnaeus) (Araneae: Sparassidae) AND ITS IMPLICATIONS IN A TROPICAL BANANA AGROECOSYSTEM . In: Journal of Global Agriculture and Ecology . tape 5 , no. 2 , 2016, ISSN  2454-4205 , p. 164 . , accessed on September 24, 2020.
  12. ↑ Jude A. Ewunken, Nelson N. Ntonifor, Mbua Christophe Parr: BIOECOLOGY OF Heteropoda venatoria (Linnaeus) (Araneae: Sparassidae) AND ITS IMPLICATIONS IN A TROPICAL BANANA AGROECOSYSTEM . In: Journal of Global Agriculture and Ecology . tape 5 , no. 2 , 2016, ISSN  2454-4205 , p. 173 . , accessed on September 24, 2020.
  13. ↑ a b Heteropoda venatoria (Linnaeus, 1767) at the Wiki der Arachnologische Gesellschaft e. V., accessed on January 6, 2021.
  14. ↑ Peter Jäger: Rarely proven spider species from Germany (Arachnidae: Araneae). In: Arachnological Messages . tape 19 , no. 1 , June 2000, pp. 53 . , accessed on September 24, 2020.
  15. ↑ a b c d e Shichang Zhang, Hong-Lin Chen, Kuan-Yu Chen, Jian-Jun Huang, Chia-Chen Chang, Dakota Piorkowski, Chen-Pan Liao, I-Min Tso: A nocturnal cursorial predator attracts flying prey with a visual lure . In: Animal Behavior . tape 102 , no. 1 , 2015, p. 123 , doi : 10.1016 / j.anbehav.2014.12.028 . , accessed January 9, 2021.
  16. ↑ a b c Mansur Ahmed, Jinnat Anam, Prasanta Kumar Saikia, Pratisha Kumari Saikia: Role of Heteropoda venotoria in Household pest Control: A comparative study . In: Asian Journal of Biological and Life Sciences . tape 3 , no. 1 , April 30, 2014, p. 21 . , accessed on January 7, 2021.
  17. ↑ a b c Mansur Ahmed, Jinnat Anam, Prasanta Kumar Saikia, Pratisha Kumari Saikia: Role of Heteropoda venotoria in Household pest Control: A comparative study . In: Asian Journal of Biological and Life Sciences . tape 3 , no. 1 , April 30, 2014, p. 22 . , accessed on January 7, 2021.
  18. ↑ Amit Kumer Neogi: Predation of Common House Gecko Hemidactylus frenatus Schlegel, 1836 by Giant Crab Spider Heteropoda venatoria Linnaeus, 1767 . In: Bugs R ALL . tape 23 , no. 1 , August 21, 2017, ISSN  2230-7052 , p. 23 . , accessed on January 7, 2021.
  19. ↑ Shichang Zhang, Hong-Lin Chen, Kuan-Yu Chen, Jian-Jun Huang, Chia-Chen Chang, Dakota Piorkowski, Chen-Pan Liao, I-Min Tso: A nocturnal cursorial predator attracts flying prey with a visual lure . In: Animal Behavior . tape 102 , no. 1 , 2015, p. 122–123 , doi : 10.1016 / j.anbehav.2014.12.028 . , accessed January 9, 2021.
  20. ↑ Dr. Rita Bhandari, Sachin R. Patil: NOTE ON REPRODUCTIVE BEHAVIOR OF THE GIANT CRAB SPIDER, HETEROPODA VENATORIA (LINNAEUS, 1767) . In: RESEARCH FIELD: ZOOLOGY . tape 6 , no. 1 , ISSN  0974-5297 , p. 121 .
  21. ↑ Jude A. Ewunken, Nelson N. Ntonifor, Mbua Christophe Parr: BIOECOLOGY OF Heteropoda venatoria (Linnaeus) (Araneae: Sparassidae) AND ITS IMPLICATIONS IN A TROPICAL BANANA AGROECOSYSTEM . In: Journal of Global Agriculture and Ecology . tape 5 , no. 2 , 2016, ISSN  2454-4205 , p. 166 . , accessed on September 24, 2020.
  22. ↑ a b c d e f John Ross, David B. Richman: The life cycle of Heteropoda venatoria (Linnaeus) (Araneae: Heteropodidae). In: Psyche A Journal of Entomology . tape 89 , no. 3-4 , January 1982, pp. 299 , doi : 10.1155 / 1982/26072 . , accessed January 6, 2021.
  23. ↑ a b c d Jude A. Ewunken, Nelson N. Ntonifor, Mbua Christophe Parr: BIOECOLOGY OF Heteropoda venatoria (Linnaeus) (Araneae: Sparassidae) AND ITS IMPLICATIONS IN A TROPICAL BANANA AGROECOSYSTEM . In: Journal of Global Agriculture and Ecology . tape 5 , no. 2 , 2016, ISSN  2454-4205 , p. 167 . , accessed on September 24, 2020.
  24. ↑ Shichang Zhang, Ho-Yin Yip, Ming-Yu Lee, Li Liu, Dakota Piorkowski, Chen-Pan Liao, I-Min Tso: Vision-mediated courtship in a nocturnal arthropod . In: Animal Behavior . tape 142 , no. 1 , June 2018, p. 187–188 , doi : 10.1016 / j.anbehav.2018.06.016 . , accessed January 9, 2021.
  25. ↑ Shichang Zhang, Ho-Yin Yip, Ming-Yu Lee, Li Liu, Dakota Piorkowski, Chen-Pan Liao, I-Min Tso: Vision-mediated courtship in a nocturnal arthropod . In: Animal Behavior . tape 142 , no. 1 , June 2018, p. 188-189 , doi : 10.1016 / j.anbehav.2018.06.016 . , accessed January 9, 2021.
  26. ↑ a b Jerome S. Rovner: VIBRATION IN HETEROPODA VENATORIA (SPARASSIDAE): A THIRD METHOD OF SOUND PRODUCTION IN SPIDERS . In: Journal of Arachnology . tape 8 , no. 1 , 1980, p. 194 . , accessed on January 7, 2021.
  27. ↑ Jerome S. Rovner: VIBRATION IN HETEROPODA VENATORIA (SPARASSIDAE): A THIRD METHOD OF SOUND PRODUCTION IN SPIDERS . In: Journal of Arachnology . tape 8 , no. 1 , 1980, p. 197 . , accessed on January 7, 2021.
  28. ↑ Jerome S. Rovner: VIBRATION IN HETEROPODA VENATORIA (SPARASSIDAE): A THIRD METHOD OF SOUND PRODUCTION IN SPIDERS . In: Journal of Arachnology . tape 8 , no. 1 , 1980, p. 196 . , accessed on January 7, 2021.
  29. ↑ a b Jerome S. Rovner: VIBRATION IN HETEROPODA VENATORIA (SPARASSIDAE): A THIRD METHOD OF SOUND PRODUCTION IN SPIDERS . In: Journal of Arachnology . tape 8 , no. 1 , 1980, p. 193 . , accessed on January 7, 2021.
  30. ↑ Jerome S. Rovner: VIBRATION IN HETEROPODA VENATORIA (SPARASSIDAE): A THIRD METHOD OF SOUND PRODUCTION IN SPIDERS . In: Journal of Arachnology . tape 8 , no. 1 , 1980, p. 194-195 . , accessed on January 7, 2021.
  31. ↑ Jerome S. Rovner: VIBRATION IN HETEROPODA VENATORIA (SPARASSIDAE): A THIRD METHOD OF SOUND PRODUCTION IN SPIDERS . In: Journal of Arachnology . tape 8 , no. 1 , 1980, p. 195 . , accessed on January 7, 2021.
  32. ↑ a b c d e f g h i Jude A. Ewunken, Nelson N. Ntonifor, Mbua Christophe Parr: BIOECOLOGY OF Heteropoda venatoria (Linnaeus) (Araneae: Sparassidae) AND ITS IMPLICATIONS IN A TROPICAL BANANA AGROECOSYSTEM . In: Journal of Global Agriculture and Ecology . tape 5 , no. 2 , 2016, ISSN  2454-4205 , p. 168 . , accessed on September 24, 2020.
  33. ^ A b c John Ross, David B. Richman: The life cycle of Heteropoda venatoria (Linnaeus) (Araneae: Heteropodidae). In: Psyche A Journal of Entomology . tape 89 , no. 3-4 , January 1982, pp. 300 , doi : 10.1155 / 1982/26072 . , accessed January 6, 2021.
  34. ↑ John Ross, David B. Richman: The life cycle of Heteropoda venatoria (Linnaeus) (Araneae: Heteropodidae). In: Psyche A Journal of Entomology . tape 89 , no. 3-4 , January 1982, pp. 301 , doi : 10.1155 / 1982/26072 . , accessed January 6, 2021.
  35. ↑ a b Yazhou Huang, Xinzhou Wu, Peng Zhang, Zhigui Duan, Xi Zhou: Peptide-rich venom from the spider Heteropoda venatoria potently inhibits insect voltage-gated sodium channels . In: Toxicon . tape 125 , January 2017, p. 44 , doi : 10.1016 / j.toxicon.2016.11.252 .
  36. ↑ a b c d MC Sanguinetti, JH Johnson, LG Hammerland, PR Kelbaugh, RA Volkmann: Heteropodatoxins: peptides isolated from spider venom that block Kv4.2 potassium channels . In: Molecular Pharmacology . tape 51 , no. 3 , March 1997, ISSN  0026-895X , p. 493 , PMID 9058605 .
  37. ^ C. Bernard, C. Legros, G. Ferrat, U. Bischoff, A. Marquardt: Solution structure of hpTX2, a toxin from Heteropoda venatoria spider that blocks Kv4.2 potassium channel. In: Protein Science: A Publication of the Protein Society . tape 9 , no. November 11 , 2000, ISSN  0961-8368 , p. 2060 , PMID 11152117 , PMC 2144494 (free full text).
  38. ↑ Renê de O. Beleboni, Andrea B. Pizzo, Andréia CK Fontana, Ruither de OG Carolino, Joaquim Coutinho-Netto: Spider and wasp neurotoxins: pharmacological and biochemical aspects . In: European Journal of Pharmacology . tape 493 , no. 1-3 , June 2004, pp. 5 , doi : 10.1016 / j.ejphar.2004.03.049 .
  39. ↑ a b Yiying Ding, Kezhi Chen, Xuewen Zhang, Tiaoyi Xiao, Jinjun Chen: Molecular diversity and evolutionary trends of cysteine-rich peptides from the venom glands of Chinese spider Heteropoda venatoria . In Review, April 24, 2020, p. 1 , doi : 10.21203 / rs.3.rs-24220 / v1 .
  40. ↑ Yazhou Huang, Xinzhou Wu, Peng Zhang, Zhigui Duan, Xi Zhou: Peptide-rich venom from the spider Heteropoda venatoria potently inhibits insect voltage-gated sodium channels . In: Toxicon . tape 125 , January 2017, p. 47 , doi : 10.1016 / j.toxicon.2016.11.252 .
  41. ↑ Zhen Xiao, Yunxiao Zhang, Jiao Zeng, Songping Liang, Cheng Tang: Purification and Characterization of a Novel Insecticidal Toxin, μ-sparatoxin-Hv2, from the Venom of the Spider Heteropoda venatoria . In: Toxins . tape 10 , no. 6 , June 7, 2018, ISSN  2072-6651 , doi : 10.3390 / toxins10060233 , PMID 29880771 , PMC 6024679 (free full text).
  42. ↑ a b Yiying Ding, Kezhi Chen, Xuewen Zhang, Tiaoyi Xiao, Jinjun Chen: Molecular diversity and evolutionary trends of cysteine-rich peptides from the venom glands of Chinese spider Heteropoda venatoria . In Review, April 24, 2020, p. 5 , doi : 10.21203 / rs.3.rs-24220 / v1 .
  43. ↑ a b Eugene Grishin: polypeptides neurotoxins from spider venoms . In: European Journal of Biochemistry . tape 264 , no. 2 , September 1999, ISSN  0014-2956 , p. 276-280 , doi : 10.1046 / j.1432-1327.1999.00622.x .
  44. ↑ a b Yazhou Huang, Xinzhou Wu, Peng Zhang, Zhigui Duan, Xi Zhou: Peptide-rich venom from the spider Heteropoda venatoria potently inhibits insect voltage-gated sodium channels . In: Toxicon . tape 125 , January 2017, p. 48 , doi : 10.1016 / j.toxicon.2016.11.252 .
  45. ↑ a b Zhen Xiao, Yunxiao Zhang, Jiao Zeng, Songping Liang, Cheng Tang: Purification and Characterization of a Novel Insecticidal Toxin, μ-sparatoxin-Hv2, from the Venom of the Spider Heteropoda venatoria . In: Toxins . tape 10 , no. 6 , June 7, 2018, ISSN  2072-6651 , p. 1 , doi : 10.3390 / toxins10060233 , PMID 29880771 , PMC 6024679 (free full text).
  46. ↑ Zhen Xiao, Yunxiao Zhang, Jiao Zeng, Songping Liang, Cheng Tang: Purification and Characterization of a Novel Insecticidal Toxin, μ-sparatoxin-Hv2, from the Venom of the Spider Heteropoda venatoria . In: Toxins . tape 10 , no. 6 , June 7, 2018, ISSN  2072-6651 , p. 5 , doi : 10.3390 / toxins10060233 , PMID 29880771 , PMC 6024679 (free full text).
  47. ↑ Yiying Ding, Kezhi Chen, Xuewen Zhang, Tiaoyi Xiao, Jinjun Chen: Molecular diversity and evolutionary trends of cysteine-rich peptides from the venom glands of Chinese spider Heteropoda venatoria . In Review, April 24, 2020, p. 11 , doi : 10.21203 / rs.3.rs-24220 / v1 .
  48. ↑ Yiying Ding, Kezhi Chen, Xuewen Zhang, Tiaoyi Xiao, Jinjun Chen: Molecular diversity and evolutionary trends of cysteine-rich peptides from the venom glands of Chinese spider Heteropoda venatoria . In Review, April 24, 2020, p. 9 , doi : 10.21203 / rs.3.rs-24220 / v1 .
  49. ↑ Heteropoda venatoria emarginata (Thorell, 1881) in the WSC World Spider Catalog , accessed on January 9 2021st
  50. ↑ Heteropoda venatoria foveolata (Thorell, 1881) in the WSC World Spider Catalog , accessed on January 9 2021st
  51. ↑ a b c d e f g h i Peter Jäger: Heteropoda Latreille 1804: new species, synonymies, transfers and records (Araneae: Sparassidae: Heteropodinae). In: Arthropoda Selecta . tape 23 , no. 2 , 2014, p. 152 . , accessed January 8, 2020.
  52. ↑ a b Jude A. Ewunken, Nelson N. Ntonifor, Mbua Christophe Parr: BIOECOLOGY OF Heteropoda venatoria (Linnaeus) (Araneae: Sparassidae) AND ITS IMPLICATIONS IN A TROPICAL BANANA AGROECOSYSTEM . In: Journal of Global Agriculture and Ecology . tape 5 , no. 2 , 2016, ISSN  2454-4205 , p. 165 . , accessed January 6, 2021.
  53. ↑ Yde Jongema: List of edible insects of the world (English). Wageningen University , April 1, 2017, accessed on February 13, 2021 .
  54. ↑ Description and husbandry report of the warm house giant crab spider on the website of "Naturaufnahme-witt" , accessed on January 20, 2020.
  55. ↑ Focus Online : Highly poisonous spider in a Bavarian supermarket? Suspicion is not confirmed , accessed on September 25, 2020.
  56. ↑ Heteropoda venatoria (Linnaeus, 1767) from Global Biodiversity Information Facility , accessed on January 19, 2020.
  57. ↑ Heteropoda venatoria (Linnaeus, 1767) at the Red List Center, accessed on January 7, 2021.

literature

Web links

Commons : Warmhaus Giant Crab Spider  - Album with pictures, videos and audio files