Cupiennius

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Cupiennius
Female of Cupiennius coccineus

Female of Cupiennius coccineus

Systematics
Class : Arachnids (arachnida)
Order : Spiders (Araneae)
Subordination : Real spiders (Araneomorphae)
Partial order : Entelegynae
Family : Fishing spiders (Trechaleidae)
Genre : Cupiennius
Scientific name
Cupiennius
Simon , 1890

The genus Cupiennius belongs to the family of fishing spiders (Trechaleidae) within the order of the weaving spiders . With Cupiennius coccineus , Cupiennius getazi and the great wandering spider ( Cupiennius salei ), the three best-known species of this family also belong to the genus, whose species occur like all other fishing spiders in Central and South America .

Both in English and in German, the species of the genus are Cupiennius occasionally as " banana spiders " (eng. Banana spiders ) called and this term share in both languages with the much more dangerous species of the genus Phoneutria of the family crest Spiders ( Ctenidae). The same also applies in the English-speaking world to the warm-house giant crab spider ( Heteropoda venatoria ), which, like the species of the genus Cupiennius, is largely harmless to humans.

features

Male of a species of the genus Cupiennius

Depending on the species, the species of the genus are medium-sized to large spiders that, like the other species in the family, have a long-legged shape. The tarsi of the legs, as in the other fishing spinning very flexible (Trechaleidae) and allow the species of the genus similar to the huntsman spider (Sparassidae) quick and agile locomotion and the ability to conform to the substrate, with a better optical merger the underground. The eyes of the genus Cupiennius are arranged in two rows, four on top of each other, of circular shape and all of the same size. They are powerful and thus allow the spiders good eyesight, which is used for both hunting and orientation. The species of the genus also have a dense cushion of well-developed sensillae (sensory hair) that are used to perceive air movements and vibrations. The dense hair enables the species, like all fishing spiders, to swim and also to submerge underwater. At the ends of the legs there are three claws for sticking to the vegetation. The drawings and colors vary depending on the type and gender.

Sexual dimorphism

Ventral view of a female of the great wandering spider ( C. salei ) with the warning colors that the males of the genus lack.

As with many spiders, those of the genus Cupiennius also have a very pronounced sexual dimorphism (difference between the two sexes). The females are built stronger than the males and often have a greater body length. On the other hand, the leg spans can be the same for both sexes, which means that the males appear longer-legged. The females of the species of the genus, in contrast to the males, have a reddish color on the ventral side , which serves as a signal color and is intended to deter predators (predators).

Similar species

The Brazilian wandering spider ( Phoneutria nigriventer ) from the family of comb spiders (Ctenidae)

Due to the similar size and shape, the larger species of the genus Cupiennius can be confused with the much more dangerous species of the genus Phoneutria from the family of comb spiders (Ctenidae), which can have dangerous effects. Confusion can also be due to the fact that species of both species are occasionally exported in banana trees to other parts of the world.

One of the main differences between the two species is their geographic distribution. The species of the genus Phoneutria are mainly represented in South America, while the main distribution of the genus Cupiennius is mainly in Central America. In addition to genital morphological features, the size of the spiders can also be used as a distinguishing feature, as some species of the genus Phoneutria are larger than those of the genus Cupiennius , and the species of the genus Phoneutria are markedly less contrasting. In some species of the genus Phoneutria , the chelicerae (jaw claws) appear reddish. Except for Cupiennius chiapanensis , this property does not occur in any other species of the genus Cupiennius .

Occurrence

Rainforest in the La Amistad National Park (here in Panama ), one of the habitats of the species of the genus Cupiennius .

The species of the genus Cupienius are without exception represented in Central and South America and inhabit the rainforests there . Within their habitat, the spiders prefer to live on larger trees, which are covered with epiphytes (plants that grow on other plants), twigs and moss and thus provide protection from the elements. The leaf funnels of bromeliads (Bromeliaceae) are particularly popular as a shelter.

Import through banana fruits

Plantation of dessert bananas ( Musa × paradisiaca ) in Costa Rica

The name "banana spiders" for the genus Cupienius stems from the fact that occasionally specimens of the four larger species Cupiennius chiapanensis , Cupiennius coccineus , Cupiennius getazi and the large wandering spider ( C. salei ) as well as the species of the genus Phoneutria which are also mentioned and are much more dangerous for humans from the family of comb spiders (Ctenidae) or also like the warm-house giant crab spider ( Heteropoda venatoria ) native to Asia, are also exported from their natural range to North America and Europe through the import of fruits of the dessert banana ( Musa × paradisiaca ). The reason for the comparatively high number of banana fruits found by these spiders can be explained by the fact that, unlike other fruits of other plants, they are not transported individually but in groups that are left on their perennials. These perennials offer the species of the genus Cupiennius and Phoneutria, as well as others, which live hidden during the day, the opportunity to hide where they can then be overlooked. With the exception of the four larger species, these transfers could not be observed in the others of the genus. Although the four species can usually be distinguished with certainty on the basis of their coloration, it is particularly advisable to examine the genital morphological characteristics of the almost identical males of Cupiennius coccineus and the great wandering spider in order to reliably identify the respective species.

In the past, some of these imports of spiders of the genus Cupiennius were not infrequently confused with species of the genus Phoneutria due to their similarity (see chapter “ Similar species ”). These mix-ups were due, among other things, to the lack of experience of the entomologists and arachnologists employed there as well as the lack of precise identification keys for precise identification at the time. In the case of these incorrect determinations, increased safety measures were already taken due to the feared danger of the spider, which turned out to be superfluous in a later and more precise identification of spiders of this genus.

Threat and protection

There is no evidence of possible endangerment of individual species of the genus Cupiennius , especially since none of the species is recorded by the IUCN . However, there are usually no threats. Accordingly, none of the species has a protection status.

Way of life

Spider of the genus Cupiennius on a bromeliad family (Bromeliaceae)

The species of the genus Cupiennius , like all fishing spiders (Trechaleidae) and also like comb spiders (Ctenidae), are nocturnal and nomadic and accordingly do not create webs of living space, but hide during the day in suitable shelters, which can also be located with visual acuity. The spider silk is therefore mainly used, similar to jumping spiders (Salticidae), as a security thread, for spinning larger prey or by the females in addition to building cocoons .

Hunting behavior and catch of prey

Cupiennius getazi with a captured grasshopper

Like other fishing spiders (Trechaleidae) and also like comb spiders (Ctenidae), the species of the genus Cupiennius do not create spider webs to catch prey, but hunt as ambulance hunters without a safety net . In addition to other invertebrates , the prey scheme also includes reptiles and amphibians in suitable sizes. Both prey and predators are located with the sense of sight and vibration. With Cupiennius coccineus it was observed that specimens of this species can locate male frogs by their croaking. These sneaked up on the frogs and then killed them in a surprise fall.

Reproduction

Young of the great wandering spider ( C. salei ) in the second skin

All species of the genus Cupiennius have a complex courtship behavior . The females use spider threads that are provided with pheromones (chemical substances that are native to the species for communication) to attract males. Once such a female has been identified and found by means of the threads, she begins a courtship dance in which she drums on the ground and shakes her opisthosoma (abdomen). This courtship behavior can often last several hours and repeat itself several times on the part of the male. A female willing to mate also answers the courtship to the male with a shake of the opisthosoma. Then the male rises on the back of the female and leads his bulbi (male sexual organs in spiders) alternately into the epigyne (female sexual organ in spiders) of his partner. Shortly after mating, the need for food of the mated female increases significantly due to the maturing eggs in it, and its opisthosoma swells significantly as a result. Three weeks after mating, the female makes her first egg cocoon , which is carried attached to the spinneret. After a month, the young hatch from the cocoon, which is previously attached to a web made by the female. After a month, the young hatch and leave the web a week after hatching. A female can make up to three more cocoons and, as is usual with fishing spiders, does not care for the brood. The young spiders, which are initially two to three millimeters in size, grow within eight and ten months. The lifespan of females of the genus is two years, that of males less.

The genus Cupiennius and human

The large wandering spider ( C. salei ) is often used as a research object due to its visual ability as shown here.

The species of the genus Cupiennius are sometimes feared because of the similarity to the genus Phoneutria of the comb spiders (Ctenidae) already mentioned . Likewise, due to their diversity, species of the genus, including the large wandering spider ( C. salei ) in particular, are used as research objects for science or otherwise receive a certain popularity of individual people, for example in pet keeping (see chapter " Terraristics ").

Toxicity and bite accidents

Closer view of a female of Cupiennius getazi with the clearly visible chelicerae

Bites of the species Cupiennius coccineus , Cupiennius getazi , Cupiennius panamensis and the large wandering spider ( C. salei ) have been reported. However, the species of the genus Cupiennius are not aggressive, but usually try to flee when disturbed and only bite in extreme distress. In addition, bites are painful, but usually remain without any medically significant symptoms. In a described bite of Cupiennius coccineus , the insertion of the chelicerae and thus the actual bite was compared with the sting of a bee. A numbness was noted as a symptom in the area of ​​the bite wound, which subsided within 10 to 30 minutes.

Terrariums

Some species of the genus Cupiennius , including the large wandering spider ( C. salei ) and Cupiennius getazi, are often kept as pets in the field of terraristics due to their imposing appearance for spiders and their striking color . Another argument in favor of keeping species of the genus is that, due to their way of life as ambulance hunters, they do not need an outlet and can therefore also be kept in comparatively small dwellings. In addition, in contrast to some ground-dwelling tarantulas (Theraphosidae) with a burrowing way of life , the spiders do not need a specially prepared substrate. The usually low risk of the species of the genus (see chapter " Toxicity and bite accidents ") would also speak in favor of keeping these spiders. For successful keeping, the temperature and humidity of the rainforests in their natural habitat should be simulated as well as possible. However, one should be aware of the high walking speed and the often shy reaction to disturbances of the species belonging to the genus.

Systematics

The genus Cupiennius was first described by Eugène Simon in 1890 and was first incorporated into the family of comb spiders (Ctenidae). Belonging to this family was questioned in 2015 by Daniele Polotow and Charles Edward Griswold . Instead, it was assumed to belong to the fishing spiders (Trechaleidae) on the basis of morphological characteristics. This was confirmed in 2019 by Luis Norberto Piacentini and Martín Javier Ramírez , so that the genus Cupiennius is now part of the fishing spider family.

The World Spider Catalog currently lists 11 species belonging to the genus. Their type is Cupiennius getazi . All species of the genus and their distribution areas are:

As of March 10, 2020

Individual evidence

  1. ↑ a b c d Friedrich G. Barth: Senses and behavior: from the life of a spider Springer-Verlag, 2002, pp. 8–396.
  2. ↑ a b c d e f g R. S. Vetter & S. Hillebrecht: Distinguishing Two Often-Misidentified Genera (Cupiennius, Phoneutria) (Araneae: Ctenidae) of Large Spiders Found in Central and South American Cargo Shipments , American Entomologist, Volume 54, Issue 2, 2008, pp. 88-93, accessed March 6, 2020.
  3. ↑ a b c d e f Francesco Tomasinelli: Cupiennius salei . The British Tarantula Society Journal , 15, 3, 2000, accessed March 6, 2020.
  4. ↑ "Banana spiders - and what's behind them" on the Lower Saxony portal , accessed on March 11, 2020.
  5. ↑ Cupiennius (Simon, 1890) in the WSC World Spider Catalog , accessed March 6, 2020.

literature

Web links

Commons : Cupiennius  - collection of images, videos and audio files