Pardosa pseudoannulata

Last updated

Pardosa pseudoannulata
Pardosa pseudoannulata.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Chelicerata
Class: Arachnida
Order: Araneae
Infraorder: Araneomorphae
Family: Lycosidae
Genus: Pardosa
Species:
P. pseudoannulata
Binomial name
Pardosa pseudoannulata
(Bösenberg & Strand, 1906)

Pardosa pseudoannulata, a member of a group of species referred to as wolf-spiders, is a non-web-building spider belonging to the family Lycosidae. P. pseudoannulata are wandering spiders that track and ambush prey and display sexual cannibalism. They are commonly encountered in farmlands across China and other East Asian countries. Their venom has properties that helps it function as an effective insecticide, and it is, therefore, a crucial pesticide control agent. [1]

Contents

Description

Pardosa pseudoannulata exhibits significant sexual dimorphism in terms of size. Females are, on average, 1.3 times larger than the males. This spider can be recognized by the ring markings on its legs and the dark bands on its carapace. The underside of these spiders is characterized by six black dots. Female P. pseudoannulata are easy to detect, as most will have an egg sac attached to their spinnerets. P. pseudoannulata have three rows of eyes with the front row having four eyes and the other rows having two eyes each. [1]

Habitat and distribution

Distribution

Pardosa pseudoannulata is widely spread across China, India, Korea, Japan and other countries in East Asia. It is most commonly found in farm fields throughout China. These spiders are commonly seen in rice fields and are the dominant predator. [1]

Habitat

Pardosa pseudoannulata commonly inhabits arable farm fields and similar open habitats. It is one of the most common surface-dwelling spider species in Central China and plays an important role as a control agent against pests and insects within the crop fields. The spider is also found near fields with ponds and has the ability to move swiftly over bodies of water. Due to the nature of agriculture, the fields will remain fallow for several months, decreasing the density of prey that migrate into the field to take advantage of nutrients in the crops. This causes P. pseudoannulata to starve for multiple months at times, explaining why they are well adapted to survive in environments with insufficient resources. [2]

In order to produce the maximum number of eggs and the highest rate of successful hatchings, Pardosa pseudoannulata prefers temperatures between 20 and 30 oC, the optimal temperature being 25 oC. If the temperature is lower than 10 oC, the spiders will stop eating and, as a result, will not grow or develop. In temperatures above 40 oC, the spiders will move slowly and remain hidden in burrows. [3]

Diet

Pardosa pseudoannulata commonly starve and have a hard time foraging for sufficient nutrients. Therefore, the occurrence of sexual cannibalism provides an adaptive strategy for female survival as well as reproductive benefits. Pre-copulation cannibalism in which the male spider is used solely as food is commonly observed in females who have already mated. The consumption of conspecifics makes up a quarter of the female's diet. Male spiders are an especially good source of nutrition because of their large size (females are 1.3 times larger) when compared to natural prey, which are insects that are several times smaller than the females. [2]

The natural prey of Pardosa pseudoannulata are rice field pests, with the rice brown planthopper, Nilaparvata lugens, as the most common. N. lugens are abundant in rice fields and detrimental to the growth of rice plants. Pardosa pseudoannulata prefers the rice brown planthopper over other pests, with the planthopper making up around 30% percent of an average spider's diet. [2] [4]

Abdomen size

Pardosa pseudoannulata’s abdomen width is an important indicator of its hunting abilities and starvation resistance. There is a trade-off between the hunting abilities and the period of time the spider can withstand hunger. Spiders with larger abdomens are seen to withstand starvation for longer periods of time, whereas spiders with smaller abdomens are seen to be better and more agile hunters. [5]

Seasonal Changes in Resource Allocation

Pardosa pseudoannulata's body mainly consists of the cephalothorax and abdomen. The sizes of these body regions strongly correlate with the energy the spider will have to hunt and the duration of time it can withstand starvation. While the size of the cephalothorax correlates strongly with hunting ability, the size of the abdomen correlates with starvation resistance. If a spiderling is in a situation where the mother deems it important for it to hunt, her resource allocation will work to increase the development of the cephalothorax. On the other hand, if there is a period of starvation expected by the mother, she will allocate resources that lead to the enlargement of the abdomen. The size of the abdomen correlates with the quantity of stored energy that can get the spider through a period of hunger. This is especially useful for spiders developing in late Autumn, as they will need the extra abdomen size to survive through overwintering, where spiders hunt at significantly lower frequencies. As result, spiderlings that emerge in November have a larger cephalothorax and abdomen, when compared to spiders that emerge in June. Also, the abdomen-cephalothorax size ratio is significantly greater for spiderlings that emerge in November than in June. Pardosa pseudoannulata varies the quantity of resources invested in the cephalothorax and abdomen and the proportional allocation of resources between the body parts depending on the season. This unique property of the spider helps it improve its overwintering survival rates. [6]

Reproduction

Pardosa pseudoannulata seen from above. Pardosa pseudoannulata in Yamaguchi.jpg
Pardosa pseudoannulata seen from above.

Pardosa pseudoannulata males and females differ in terms of sexual behavior. Females are monandrous, meaning that they only mate with one male at a time. This motivates the evolution of sexual cannibalism for males, as the male will parent all of the female's offspring, making the paternal investment worthwhile. On the other hand, males are polygynous if not cannibalized. [7]

Females are able to store sperm from a copulation and use it produce multiple egg sacs. This prevents them from being motivated to mate again. The result is higher aggression rates in female spiders who have previously mated. [1]

Females will carry their sac filled with eggs connected to their spinnerets. This will detach when it is time for the offspring to be born. The new offspring will crawl onto the mother's abdomen and stay there for 5 days. During this time, they will feed off of the remains of their yolk from the mother's eggs. After this period, they will move into the leaf litter and detach live from the mother. [1]

Copulation duration for Pardosa pseudoannulata ranges from 19 to 93 minutes. The duration of copulation is significantly higher with males that are cannibalized. Copulation duration is independent of the sperm count of the male. Male spiders will need up to seven days in order to replenish their sperm count. For females, reproducing with a male that has recently mated and has a low sperm count will lead to a lower chance of reproductive success. The sperm count of the male has no impact on copulation duration or intensity, so it is believed that females are unable to distinguish males with high sperm counts from males with low sperm counts. [7]

Life cycle

Pardosa pseudoannulata will have on average two and a half generations per year. Similar to other Pardosa species, sub-adults and adults overwinter in order to conserve energy and survive the cold winter months. Overwintering adults will be inactive from November to March as they save up body mass. They will burrow into the soil or use litter in their natural habitat as shelter. They will reach their reproductive peak in early May, and this peak is usually consists of the overwintering generation. A second reproductive peak is observed in early July with the second generation. A third one can be seen in late September with the following generation.   [1]

Behavior

Sexual cannibalism

Pardosa pseudoannulata engages in sexual cannibalism as a foraging strategy. Conspecific prey can make up 25% of the female's diet. The female spider uses sexual cannibalism as a way to attain nutrition and increase offspring survival. There are instances where the female spider will attack and cannibalize the male before or after copulation, the latter being observed more frequently. The rate at which females attack males is dependent on the female's hunger level and mating history. Spiders that are well-fed and virgins are less likely to attack males and perform pre-copulative cannibalism. The reason why starved females are more aggressive is because they have more motivation to acquire nutrition. Interestingly, the rate of cannibalization occurring did not change with the female's sexual history or hunger state. Aside from this, male size is also a significant factor in cannibalization rates. As mate size dimorphism, the difference between the sizes of mates, increases, sexual cannibalism occurs more frequently. [1]

Sexual cannibalism increases offspring survival in Pardosa pseudoannulata. This is mainly due to the mother's ability to care for offspring as a result of nutrition derived through cannibalism. The presence of sexual cannibalism does not have any influence on fecundity, as cannibalistic and non-cannibalistic females produce the same amount of offspring. Another benefit of sexual cannibalism to the female is the increase in body mass through the nutrients in the male body. [1]

Male Pardosa pseudoannulata Pardosa.pseudoannulata.male.-.tanikawa.jpg
Male Pardosa pseudoannulata

Male benefit in sexual cannibalism

From the male spider's perspective, sexual cannibalism proves beneficial as well, given that cannibalism occurs after copulation. Each copulatory approach is a risk taken by the male, as there is always a chance that the female might cannibalize the male pre-copulation. In this scenario, the male loses all of its future opportunities to reproduce. Additionally, being cannibalized before copulation increases the survival rates of rival males’ offspring. On the other hand, if copulation is successful, the male benefits. The male gets an opportunity to propagate his genes through his offspring by sacrificing his body in the form of paternal investment. As the females are monandrous, the male is guaranteed to father all offspring produced by the female. [7]

Courting behavior

Pardosa pseudoannulata males display unique courting behavior. This display includes pounding the floor with the first pair of legs. This courting behavior is sustained until the female acts on the male. If the male senses a lunge, or an aggressive behavior from the female, it will attempt to escape. Most males are able to avoid cannibalism through escaping the female. However, if the lunge of the female is successful and the male is caught, the female almost always cannibalizes the male. [1]

Prey Capture

Pardosa pseudoannulata do not weave webs, but instead will ambush, or chase, their prey in order to capture them. Genomic inspection has shown that they are significantly lacking in genes responsible for silk web production when compared to the genes for neurotoxic venom production. [1] Pardosa pseudoannulata uses an immobilizing venom rather than a web. Its venom has been effective against numerous pests that infest arable crop fields. Because of this, there is a lot of research that focuses on using the venom of Pardosa pseudoannulata as a pesticide in order to maximize crop yields in rice farms. The studied venom is shown to be very selective in its target and will only immobilize certain species that Pardosa pseudoannulata comes in contact with. P. pseudoannulata venom is generally harmless to humans, although it can cause rashes or minor allergic reactions. [8]

Related Research Articles

<span class="mw-page-title-main">Argiope bruennichi</span> Species of orb-weaver spider.

Argiope bruennichi is a species of orb-web spiders distributed throughout Central and Northern Europe, North Africa, parts of Asia, and the Azores archipelago. Like many other members of the genus Argiope, it has strikingly yellow and black markings on its abdomen.

<i>Misumena vatia</i> Species of spider

Misumena vatia is a species of crab spider with a holarctic distribution. In North America, it is called the goldenrod crab spider or flower (crab) spider, as it is commonly found hunting in goldenrod sprays and milkweed plants. They are called crab spiders because of their unique ability to walk sideways as well as forwards and backwards. Both males and females of this species progress through several molts before reaching their adult sizes, though females must molt more to reach their larger size. Females can grow up to 10 mm (0.39 in) while males are quite small, reaching 5 mm (0.20 in) at most. Misumena vatia are usually yellow or white or a pattern of these two colors. They may also present with pale green or pink instead of yellow, again, in a pattern with white. They have the ability to change between these colors based on their surroundings through the molting process. They have a complex visual system, with eight eyes, that they rely on for prey capture and for their color-changing abilities. Sometimes, if Misumena vatia consumes colored prey, the spider itself will take on that color.

<span class="mw-page-title-main">Spider cannibalism</span> Spiders consuming all or part of another individual of the same species as food

Spider cannibalism is the act of a spider consuming all or part of another individual of the same species as food. It is most commonly seen as an example of female sexual cannibalism where a female spider kills and eats a male before, during, or after copulation. Cases of non-sexual cannibalism or male cannibalism of females both occur but are notably rare.

<i>Metellina segmentata</i> Species of spider

Metellina segmentata is a spider in the family Tetragnathidae with a Palaearctic distribution. This spiders name is often shortened to Meta segmentata, and some even call it Araneus segmentatus simply meaning, orb weaving spiders. It is primarily found in Europe, with the highest number in the United Kingdom, but the species has also been introduced to Canada.

<span class="mw-page-title-main">Sexual cannibalism</span> Practice of animals eating their own mating partners

Sexual cannibalism is when an animal, usually the female, cannibalizes its mate prior to, during, or after copulation. It is a trait observed in many arachnid orders and several insect and crustacean clades. Several hypotheses to explain this seemingly paradoxical behavior have been proposed. The adaptive foraging hypothesis, aggressive spillover hypothesis and mistaken identity hypothesis are among the proposed hypotheses to explain how sexual cannibalism evolved. This behavior is believed to have evolved as a manifestation of sexual conflict, occurring when the reproductive interests of males and females differ. In many species that exhibit sexual cannibalism, the female consumes the male upon detection. Females of cannibalistic species are generally hostile and unwilling to mate; thus many males of these species have developed adaptive behaviors to counteract female aggression.

<i>Trichonephila plumipes</i> Species of spider

Trichonephila plumipes, the Pacific golden orb weaver, is a species of spider found in Australia, Indonesia and some Pacific Islands, which exhibits extreme sexual dimorphism through its sexual cannibalism behavior. It is sometimes called the tiger spider due to its markings which look similar to a tiger. This species was formerly called Nephila plumipes. As with other spiders from the genus Nephila, these spiders have a distinct golden web.

<span class="mw-page-title-main">Six-spotted fishing spider</span> Species of spider

The six-spotted fishing spider is an arachnid from the nursery web spider family Pisauridae. This species is from the genus Dolomedes, or the fishing spiders. Found in wetland habitats throughout North America, these spiders are usually seen scampering along the surface of ponds and other bodies of water. They are also referred to as dock spiders because they can sometimes be witnessed quickly vanishing through the cracks of boat docks. D. triton gets its scientific name from the Greek mythological god Triton, who is the messenger of the big sea and the son of Poseidon.

<i>Hogna carolinensis</i> Species of spider

Hogna carolinensis, commonly known as the Carolina wolf spider and giant wolf spider, is found across North America. It is the largest of the wolf spiders in North America, typically measuring at 18–20 mm for males and 22–35 mm for females.

<i>Pisaurina mira</i> Species of spider

Pisaurina mira, also known as the American nursery web spider, is a species of spider in the family Pisauridae. They are often mistaken for wolf spiders (Lycosidae) due to their physical resemblance. P. mira is distinguished by its unique eye arrangement of two rows. 

<i>Pardosa amentata</i> Species of spider

Pardosa amentata, otherwise known as the wolf spider or spotted wolf spider is a species of spider in the genus Pardosa belonging to the family of wolf spiders, Lycosidae. The species has a widespread distribution in central Europe and northwestern Europe and are commonly found on the British Isles. The species hunts its prey on the ground rather than weaving a web.

<span class="mw-page-title-main">Sexual selection in spiders</span>

Sexual selection in spiders shows how sexual selection explains the evolution of phenotypic traits in spiders. Male spiders have many complex courtship rituals and have to avoid being eaten by the females, with the males of most species survive a few matings, and having short life spans.

<i>Tigrosa helluo</i> Species of spider

Tigrosa helluo is a species of spider belonging to the family Lycosidae, also known as wolf spiders. T. helluo was formerly known as Hogna helluo before differences between dorsal color patterns, habitat preferences, body structures, etc. were discovered. The species is native to the United States, Canada, and Mexico. It can be found across the eastern half of the United States, primarily in the Northeast and New England, and as far west as Nebraska and Kansas. T. helluo can be found in diverse habitats including woods, marshes, fields, and riparian areas. Typically, members of this species prefer to live in wetter areas as opposed to dry environments. Males tend to live for around a year and females will live for close to two years.

Agelenopsis pennsylvanica, commonly known as the Pennsylvania funnel-web spider or the Pennsylvania grass spider, is a species of spider in the family Agelenidae. The common name comes from the place that it was described, Pennsylvania, and the funnel shape of its web. Its closest relative is Agelenopsis potteri.

<i>Pardosa milvina</i> Species of arachnid

Pardosa milvina, the shore spider, is a species in the wolf spider family. They are mainly found near rivers and in agricultural areas in eastern North America. P. milvina feed on a large variety of small insects and spiders. Ground beetles such as Scarites quadriceps and large wolf spiders such as Tigrosa helluo are predators of P. milvina. P. milvina are smaller spiders with thin, long legs. This species captures prey such as arthropods with their legs and then kills them with their venom. Their predators are larger wolf spiders and beetles. P. milvina are able to detect these predators from chemotactile and vibratory cues. These spiders lose limbs when escaping from predators and they can change their preferred location in order to avoid predators. P. milvina also use chemical cues in order to mate. During their mating ritual, the male raises his legs and shakes his body. Both males and females can use silk, a chemotactile cue, for sexual communication. Additionally, female shore spiders heavily invest in their offspring, keeping them in egg sacs and carrying them for a few weeks after they are born.

<i>Schizocosa ocreata</i> Species of spider

Schizocosa ocreata is a species of wolf spider in the family Lycosidae that is found in North America. The Schizocosa ocreata is a spider that is most commonly known as the “brush-legged wolf spider” because of their distinct dark-colored fur-like coverings around their legs. The S. ocreata are commonly found in North American states, usually in the middle and eastern United States.

<i>Leucauge mariana</i> Species of spider

Leucauge mariana is a long-jawed orb weaver spider, native to Central America and South America. Its web building and sexual behavior have been studied extensively. Males perform several kinds of courtship behavior to induce females to copulate and to use their sperm.

<i>Pardosa agrestis</i> Species of spider

Pardosa agrestis is a non-web-building spider in the family Lycosidae, commonly known as wolf spiders.

Schizocosa stridulans is a sibling species of S. ocreata and S. rovneri and is part of the wolf spider family. The name of the genus comes from the epigynum structure being lycosid and having a split T excavation. This spider is well-known for its specific leg ornamentation and courtship rituals and that is how it has been differentiated from its related species. The S. stridulans take systematic steps during its courtship ritual, which involves two independent signals. More specifically, female spiders will leave silk and pheromones to communicate that they are ready to mate.

Latrodectus revivensis, also known as the desert widow, is a species of venomous spider belonging to the Latrodectus genus and located in the Negev desert and the Arava valley (Arabah).

<i>Larinia jeskovi</i> Species of arachnid

Larinia jeskovi is a species of the family of orb weaver spiders and a part of the genus Larinia. It is distributed throughout the Americas, Africa, Australia, Europe, and Asia and commonly found in wet climes such as marshes, bogs, and rainforests. Larinia jeskovi have yellow bodies with stripes and range from 5.13 to 8.70 millimeters in body length. They build their webs on plants with a small height above small bodies of waters or wetlands. After sunset and before sunrise are the typical times they hunt and build their web. Males usually occupy a female's web instead of making their own. The mating behavior is noteworthy as male spiders often mutilate external female genitalia to reduce sperm competition while female spiders resort to sexual cannibalism to counter such mechanisms. The males also follow an elaborate courtship ritual to attract the female. The bite of Larinia jeskovi is not known to be of harm to humans.

References

  1. 1 2 3 4 5 6 7 8 9 10 Wu, Lingbing, and Huaping Zhang. “Factors Influencing Sexual Cannibalism and Its Benefit to Fecundity and Offspring Survival in the Wolf Spider Pardosa Pseudoannulata (Araneae: Lycosidae).” Behavioral Ecology and Sociobiology, vol. 67, 2013, doi : 10.1007/s00265-012-1440-2.
  2. 1 2 3 Chesson, J.., et al. “Prey Preference of the Wolf Spider, Pardosa Pseudoannulata (Boesenberg Et Strand).” Population Ecology, Springer-Verlag, 1 Jan. 1978, link.springer.com/article/10.1007/BF02513547.
  3. Xiao, Rong, and Liang Wang. “Transcriptome Response to Temperature Stress in the Wolf Spider Pardosa Pseudoannulata (Araneae: Lycosidae).” Ecology and Evolution, vol. 6, no. 11, 20 Apr. 2016, doi : 10.1002/ece3.2142.
  4.  Preap, Visarto, and Myron Zalucki. “Effectiveness of Brown Planthopper Predators: Population Suppression by Two Species of Spider, Pardosa Pseudoannulata (Araneae, Lycosidae) and Araneus Inustus (Araneae, Araneidae).” Journal of Asia-Pacific Entomology, vol. 4, no. 2, Nov. 2001, doi : 10.1016/S1226-8615(08)60122-3.
  5. Iida, Hiroyuki. “Trade-off between Hunting Ability and Starvation Tolerance in the Wolf Spider, Pardosa Pseudoannulata (Araneae: Lycosidae).” Applied Entymology and Zoology, vol. 40, no. 1, 2005, doi : 10.1303/aez.2005.47.
  6. Iida, H.; Fujisaki, K. (2007). "Seasonal changes in resource allocation within an individual offspring of the wolf spider, Pardosa pseudoannulata (Araneae: Lycosidae)". Physiological Entomology. 32 (1): 81–86. doi:10.1111/j.1365-3032.2006.00545.x. ISSN   1365-3032. S2CID   85697771.
  7. 1 2 3 Gong, Deyong. “Mating Experience Affects Male Mating Success, but Not Female Fecundity in the Wolf Spider Pardosa Pseudoannulata (Araneae: Lycosidae).” Behavioral Processes, vol. 167, Oct. 2019, doi : 10.1016/j.beproc.2019.103921.
  8. Yu, Na. “Genome Sequencing and Neurotoxin Diversity of a Wandering Spider Pardosa Pseudoannulata (Pond Wolf Spider).” Biorxiv, 29 Aug. 2019, doi : 10.1101/747147.