Philodromus cespitum

Last updated

Philodromus cespitum
Philodromus cespitum 090801.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Chelicerata
Class: Arachnida
Order: Araneae
Infraorder: Araneomorphae
Family: Philodromidae
Genus: Philodromus
Species:
P. cespitum
Binomial name
Philodromus cespitum
(Walckenaer, 1802)

Philodromus cespitum is a species of running crab spider in the family Philodromidae. It is found in North America, Europe, North Africa, and parts of the Middle East and Asia. P. cespitum is a foliage-dweller, and is the most abundant species found in European fruit orchards. It acts as a biological control by preying on orchard pests. P. cespitum is a diurnal ambush hunter and preys on aphids, insects, and occasionally competitor spider species. Males court females by tapping on the females’ bodies with their forelegs. They then insert a genital plug into the female during copulation. Unlike in many other spider species, subsequent males can mate with plugged females by removing part of the plug prior to copulation. Males discriminate among females based on virginity and plug size, and can determine these factors using the females’ draglines and plug samples.

Contents

Philodromus cespitum.jpg

Description

Males of this species are approximately 3.5-5.0 mm long, and females are about 5.3 mm long. Body color is variable, mostly in shades of brown or yellow. Spots are also a common body pattern. Males tend to have more spots than females. Legs are usually yellowish brown or grey. Some members of the species also have spots on their legs. [1] Males of the species have a noticeably asymmetric sperm duct. [2] Male pedipalps contain nerve tissue and a sensory organ. [3]

Phylogeny

Philodromus cespitum belongs to the Philodromus aureolus species complex. P. cespitum is the only species in this group that is Holarctic . Since different species in this group are distinguished by copulatory organs that are only fully visible when mature, spiderlings of different species in the group are difficult to tell apart. [4]

Philodromus lividus and Philodromus longipalpis were originally thought to be subspecies of P. cespitum. Since no evidence was found to place them in the subspecific category, they were made their own species. Males of P. lividus and P. cespitum have differently shaped sperm ducts. Female P. longipalpis have a larger median plate and atrium of the epigyne than P. cespitum. [5]

Philodromus fuscolimbatus, another species in the Philodromus aureolus species group, was also originally thought to be a subspecies of P. cespitum.  However, the two species can be differentiated by the shapes of their sperm ducts. Sympatry occurs between P. cespitum and P. fuscolimbatus in the northern Alps, a region where the two species overlap. [6]

Philodromus cespitum can also coexist with related species Philodromus albidus and Philodromus aureolus in the same geographic area. They accomplish this by occupying different trophic and habitat niches. [7]

Females of the species Philodromus buchari very closely resemble females of P. cespitum, although P. buchari are slightly larger. [4]

Neural arrangement in the pedipalps of male cave spiders Hickmana troglodytes is almost identical to the neural arrangement in the pedipalps of male P. cespitum. [3]

Habitat and distribution

Philodromus cespitum is a foliage-dweller, [8] and is the dominant species found in Central European fruit orchards. [9] It is more highly concentrated in orchard centers than edges. Larger individuals are found in the center and smaller individuals are found around the edges. [10] This species is also found in cotton fields. [11] P. cespitum is distributed across North America, Europe, North Africa, Turkey, Russia, Kazakhstan, China, Korea, and Japan. [1] Adult females are most commonly observed in June and July. Spiderlings are present year-round but are most abundant from August to October. [12]

Activity

Males are more active during the day than females, and females are more active at dawn and dusk. Both sexes show locomotor activity indicative of a twenty-four hour circadian rhythm cycle. However, the exact effect of these circadian rhythms on locomotion differs between males and females. Females also possess a secondary twelve hour cycle. [13]

Diet

Philodromus cespitum are diurnal hunters. [13] They capture their prey mainly through ambush. [8] They feed on insects and spiders found in fruit orchards, such as aphids, the pest Cacopsylla pyri , and Theridion spiders. They sometimes engage in intraguild predation, in which they feed on competitor species as well as smaller prey. A diet of both competitor spiders and aphids increases the overall fitness of P. cespitum. However, since the costs are high due to retaliation and risk of injury from the competitor spider, intraguild predation does not often occur. [14]

Foraging aggressiveness in P. cespitum can sometimes lead to overkilling, where the organism kills more prey than it can consume. Aggressiveness in this species is positively correlated with size and capture success. Aggressiveness also significantly increases the probability of intraguild predation. [10]

Reproduction and life cycle

Females lay around 250 eggs and construct five to seven egg cocoons. Females build egg cocoons during oviposition. The number of eggs laid is not affected by changes in temperature. The number of larvae that hatch decreases after the third egg cocoon built. [15]

The time from oviposition to hatching is 20 days at 15 °C and 10 days at 24 °C. The developmental time of nymph-stages is about 430 days. Developmental time is longer for females than for males regardless of temperature. [15]

Females of this species tend to live longer than males. The lifespan of both sexes in a laboratory setting is shorter when housed together than when individually housed. [15]

Mating

Courtship

A male will initiate courtship by tapping the female’s body with his forelegs. Males who have a proportionally larger femur length in comparison to the females they are courting perform more taps than mating pairs who have a more similar ratio. The female may first run away and push away the male’s forelegs with her own legs. The male pursues the female until she stops moving and then taps continuously as he climbs over her body. The male then enters the mating position, in which he faces towards the tip of the female’s opisthosoma. He inserts one of his pedipalps into one of the female’s copulatory organs and transfers sperm and genital plug material via the pedipalp. The female ends the copulation by shaking her body to dislodge the male. The male then attempts to restart the courtship process and mount the female again. The female will either allow him to mount again or will shake him off until he ceases the behavior. Females normally allow the male to engage in two to three rounds of courtship and copulation. [16]

Genital plugs

Male spiders plug female genitalia when transferring sperm during copulation. The plugs are stored in the males’ genital bulb and they are amorphous. Since they do not have a complicated shape or structure, genital plugs are low cost for the male to produce. Plug size and quality are positively correlated with the number of times that the male taps the female’s body during courtship.

Genital plugs are made up of a mixture of compressed vesicles and spermatozoa. They extend halfway into the copulatory duct, with the other half being filled with only spermatozoa.

In many species, genital plugging prevents copulation with future males. In P. cespitum, however, males can mate even with fully plugged females by removing some of the plugs prior to mating. Females may determine the amount of plug material that a male deposits by choosing when to end the copulation. The amount of material deposited increases with increasing duration of female haematodocha expansion.

When males are mated with females who already possess plugs rather than virgin females, the females tend to be more aggressive. They will often bite the males’ legs during courtship, and sperm transfer occurs less frequently. However, males are usually able to remove some of the plug material and mate with the female. Since the male must expend energy removing the plug and is not able to transfer as much sperm, this benefits the male who originally plugged the female. This may explain why plugs are still produced even though they can be removed by a future male. [16]

Male mate choice

Males discriminate and prefer silk draglines from virgin females over mated females. They also prefer virgin females and mated females with small plugs to mated females with large plugs [17] because they do not need to expend as much energy on removing the plug and will be able to transfer more sperm when copulating.

Enemies

Parasitism by organisms such as the small-headed fly Ogcodes fumatus can sometimes occur. The observed rate of parasitism in P. cespitum is 2.5%. P. cespitum exhibit abnormal web-building behaviors prior to the emergence of the larva parasite. [18] Chrysoperla carnea and Coccinella septempunctata are natural enemies of P. cespitum. [19]

Interactions with humans and livestock

Philodromus cespitum acts as a biological control agent by feeding on pests in fruit orchards. [9] Because fruit orchards are one of the main habitats of P. cespitum, they are affected by the insecticides sprayed against the pests that they consume. P. cespitum exhibit different prey preferences when in the presence of insecticides. This may be due to an impaired sensory system, taste, or mobility as a result of the insecticides. [20]

Insecticides also increase the foraging aggressiveness of P. cespitum. This may be due to reduced prey availability or behavioral changes as a result of altered internal states or gene expression. [20]

Insecticides can also be harmful to P. cespitum, with different types causing different mortality rates, ranging from 0 to 80%. Since these spiders are beneficial to farmers in that they consume fruit orchard pests, insecticides that cause a lower mortality rate can work in conjunction with the spider to eliminate pests. [9]

Philodromus cespitum also acts as an important biological control in Chinese and Iranian cotton fields by preying on cotton pests. [11]

Neonicotinoids

Neonicotinoids are typically effective in pest control, yet spiders are less sensitive to them given the altered structure of their acetylcholine receptors where the neonicotinoids bind selectively. Imidacloprid has quite severe effects with partial lethality after an hour. Acetamiprid has sublethal effects which are higher when the chemical is applied on the dorsal side. More males than females either are paralyzed or die with the dorsal application of neonicotinoids. This finding is consistent not only with P. cespitum but also with other prevalent spider families. [21]

Related Research Articles

<i>Philodromus</i> Genus of spiders

Philodromus is a genus of philodromid crab spiders. Spiders in this genus are distinctively flattened.

<i>Hickmania</i> Genus of spiders

Hickmania is a monotypic genus of Australian cribellate araneomorph spiders in the family Gradungulidae, containing only the Tasmanian cave spider. The genus was first described by Willis J. Gertsch in 1958, and has been found only in Tasmania. It is the last of an old Gondwanan lineage, long since separated from its closest relatives in South America. It is an icon species for faunal conservation in Tasmania, and is named in honor of V. V. Hickman, a professor at the University of Tasmania, who specialized in spiders. The species name is derived from the Ancient Greek τρωγλοδύτης (troglodytes), meaning "cave-dweller".

<span class="mw-page-title-main">Entelegynae</span> Clade of spiders

The Entelegynae or entelegynes are a subgroup of araneomorph spiders, the largest of the two main groups into which the araneomorphs were traditionally divided. Females have a genital plate (epigynum) and a "flow through" fertilization system; males have complex palpal bulbs. Molecular phylogenetic studies have supported the monophyly of Entelegynae.

<span class="mw-page-title-main">Sexual conflict</span> Term in evolutionary biology

Sexual conflict or sexual antagonism occurs when the two sexes have conflicting optimal fitness strategies concerning reproduction, particularly over the mode and frequency of mating, potentially leading to an evolutionary arms race between males and females. In one example, males may benefit from multiple matings, while multiple matings may harm or endanger females, due to the anatomical differences of that species. Sexual conflict underlies the evolutionary distinction between male and female.

<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, several insect and crustacean clades, gastropods, and some snake species. 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>Unicorn</i> (spider) Genus of spiders

Unicorn ("one horn", in Latin) is a genus of goblin spiders from South America, containing seven species that occur predominantly in high elevation, semi-desert regions of Bolivia, Chile, and Argentina. Individuals are relatively large for goblin spiders, measuring up to 3.0 mm (0.12 in) in body length. The genus name refers to a characteristic pointed projection between the eyes and jaws of males. In at least one species, broken-off tips of the male pedipalps have been found within the genitalia of females, postulated as a means of sperm competition. Unicorn possesses several traits that suggest it is a relatively "primitive" member of the Oonopidae, and is classified with other similar, soft-bodied goblin spiders in the subfamily Sulsulinae.

<i>Pholcus phalangioides</i> Species of spider

Pholcus phalangioides, commonly known as the cosmopolitan cellar spider, long-bodied cellar spider or one of various types called a daddy long-legs spider, is a spider of the family Pholcidae. It is also known as the skull spider, since its cephalothorax is said to resemble a human skull. This is the only spider species described by the Swiss entomologist Johann Kaspar Füssli, who first recorded it in 1775. Its common name of "daddy long-legs" should not be confused with a different arachnid group with the same common name, the harvestman (Opiliones), or the crane flies of the superfamily Tipuloidea.

Monogyny is a specialised mating system in which a male can only mate with one female throughout his lifetime, but the female may mate with more than one male. In this system, the males generally provide no paternal care. In many spider species that are monogynous, the males have two copulatory organs, which allows them to mate a maximum of twice throughout their lifetime. As is commonly seen in honeybees, ants and certain spider species, a male may put all his energy into a single copulation, knowing that this will lower his overall fitness. During copulation, monogynous males have adapted to cause self genital damage or even death to increase their chances of paternity.

<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>Holocnemus pluchei</i> Species of spider

Holocnemus pluchei, commonly known as the marbled cellar spider, is a species of Pholcidae, a family commonly referred to as "cellar spiders" or "daddy long-legs". This species is distributed across the North Pacific region of the United States, as well as in parts of North Africa, Europe, and the Mediterranean. It is considered a common household spider and builds its nest in attics, basements, and eaves of houses. Although some members of the species live in solitary webs, the majority join already existing webs and migrate to new webs multiple times throughout the course of their lives. A unique feature of H. pluchei is that while in many species of spiders, stridulation commonly occurs by males during sexual encounters, in H. pluchei, females also possess stridulatory organs, and both sexes engage in stridulation.

<span class="mw-page-title-main">Palpal bulb</span> Part of a pedipalp of a male spider

The two palpal bulbs – also known as palpal organs and genital bulbs – are the copulatory organs of a male spider. They are borne on the last segment of the pedipalps, giving the spider an appearance often described as like wearing boxing gloves. The palpal bulb does not actually produce sperm, being used only to transfer it to the female. Palpal bulbs are only fully developed in adult male spiders and are not completely visible until after the final moult. In the majority of species of spider, the bulbs have complex shapes and are important in identification.

<i>Philodromus aureolus</i> Species of spider

Philodromus aureolus, the wandering crab spider, is a mainly European running crab spider of the family Philodromidae. The taxonomy of the species group named after Philodromus aureolus is in a state of flux and a number of new species have recently been recognised.

<i>Stenaelurillus modestus</i> Species of spider

Stenaelurillus modestus is a species of jumping spider in the genus Stenaelurillus that lives in South Africa. It was first described in 2014 by Wanda Wesołowska. The species is a specialist that preys on Odontotermes termites, although its venom is also effective against other prey. The spider is medium-sized, with a brown cephalothorax between 2.0 and 2.7 mm in length and a black abdomen between 1.9 and 2.8 mm long. It is generally black in colour. The carapace has a border of white hairs and the abdomen is edged with bristles. It is distinguished from other members of the genus by the male's elongated palpal bulb and straight embolus, and the horseshoe-shaped depression in the female's epigyne.

<i>Eris militaris</i> Species of spider

Eris militaris, known commonly as the bronze jumper or bronze lake jumper, is a species of jumping spider, belonging to the Salticidae family. It is found in the United States and Canada within both suburban and rural areas. The male and female of this species can be differentiated from their size or by the coloration on their cephalothorax and abdomen. The females have a lighter cephalothorax a slightly darker abdomen with white spots. They are active in the autumn and winter season and can be found in sheltered areas within vegetation. They can also be found living within apple orchards, where insecticides may be present, which can potentially effect or alter their personality and behavior. Their diet consists of small insects, almost anything they can hold.

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>Mecaphesa celer</i> Species of spider

Mecaphesa celer, known generally as the swift crab spider, is a species of crab spider in the family Thomisidae. Its range is quite large, and it is found throughout much of North and Central America.

<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 pseudoannulata</i> Species of arachnid

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.

<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.

Zodarion wesolowskae is a species of ant spider in the genus Zodarion that lives in Morocco. The species was first described in 2020 by Souâd Benhalima and Robert Bosmans. Only the male has been described, although Benhalima and Bosmans suggest that the female could be one of the spiders described as Zodarion trianguliferum. The spider is small, typically 3.4 mm (0.13 in) long, with a plain brown to dark brown carapace and a black abdomen which has faint white stripes. The spider is a member of the mostafai group within the genus, which lack a tooth at the end of the embolus. It can be further distinguished from other members of the genus by its very long and thin tibial apophysis. The genus Zodarion is known to use ant mimicry for both defence against predators and to deceive ants to prey on them. This attribute could be used as a form of biological pest control.

References

  1. 1 2 Gloor, Daniel; Blick, Theo; Nentwig, Wolfgang; Kropf, Christian; Hänggi, Ambros (2010). "Spiders of Europe". doi:10.24436/1.{{cite journal}}: Cite journal requires |journal= (help)
  2. Muster, Christoph; Thaler, Konrad (2004). "New Species and Records of Mediterranean Philodromidae (Arachnida, Araneae): I. Philodromus Aureolus Group" (PDF). Zugleich Kataloge der OÖ: 305–326.
  3. 1 2 Sentenská, Lenka; Müller, Carsten H.G.; Pekár, Stano; Uhl, Gabriele (December 2017). "Neurons and a sensory organ in the pedipalps of male spiders reveal that it is not a numb structure". Scientific Reports. 7 (1): 12209. Bibcode:2017NatSR...712209S. doi:10.1038/s41598-017-12555-5. PMC   5610179 . PMID   28939892.
  4. 1 2 Kubcova, Lenka (2004). "A New Spider Species from the Group Philodromus Aureolus (Araneae, Philodromidae) in Central Europe" (PDF). Zugleich Kataloge der OÖ: 291–304.
  5. Segers, Hendrik (1992). "Nomenclatorial notes on, and redescriptions of some little know species of the P. aureolus-group (Araneae: Philodromidae)" (PDF). Bulletin of the British Arachnological Society. 9 (1): 19–25. hdl:1854/LU-232630.
  6. "Philodromus cespitum (Walckenaer, 1802)". World Spider Catalog.
  7. Michalko, Radek; Pekár, Stano (2015). "Niche partitioning and niche filtering jointly mediate the coexistence of three closely related spider species (Araneae, Philodromidae)". Ecological Entomology. 40 (1): 22–33. doi:10.1111/een.12149. S2CID   84345319.
  8. 1 2 Michalko, Radek; Řežucha, Radomil (July 2018). "Top predator's aggressiveness and mesopredator's risk-aversion additively determine probability of predation". Behavioral Ecology and Sociobiology. 72 (7): 105. doi:10.1007/s00265-018-2520-8. S2CID   46968950.
  9. 1 2 3 Řezáč, Milan; Pekár, Stano; Stará, Jitka (1 August 2010). "The negative effect of some selective insecticides on the functional response of a potential biological control agent, the spider Philodromus cespitum". BioControl. 55 (4): 503–510. doi:10.1007/s10526-010-9272-3. S2CID   29796266.
  10. 1 2 Michalko, Radek; Dvoryankina, Viktoriya (June 2019). "Intraspecific phenotypic variation in functional traits of a generalist predator in an agricultural landscape". Agriculture, Ecosystems & Environment. 278: 35–42. doi:10.1016/j.agee.2019.03.018. S2CID   133590880.
  11. 1 2 Ghavami, Sahra (2008). "The Potential of Predatory Spiders as Biological Control Agents of Cotton Pests in Tehran Provinces of Iran" (PDF). Asian Journal of Experimental Sciences. 22 (3): 303–306.
  12. Miliczky, Eugene R.; Horton, David R.; Calkins, Carrol O. (December 2008). "Observations on phenology and overwintering of spiders associated with apple and pear orchards in south-central Washington". Journal of Arachnology. 36 (3): 565–573. doi:10.1636/T07-29.1. S2CID   73518332.
  13. 1 2 Mezofi, Laszlo; Marko, Gabor; Kovacs, Peter; Marko, Viktor (28 May 2019). "Circadian rhythms in the locomotor activity of the spiders Carrhotus xanthogramma (Salticidae) and Philodromus cespitum (Philodromidae): Temporal patterns and sexual differences". European Journal of Entomology. 116: 158–172. doi: 10.14411/eje.2019.017 .
  14. Michalko, Radek; Dvoryankina, Viktoriya (1 June 2019). "Intraspecific phenotypic variation in functional traits of a generalist predator in an agricultural landscape". Agriculture, Ecosystems & Environment. 278: 35–42. doi:10.1016/j.agee.2019.03.018. S2CID   133590880.
  15. 1 2 3 Klein, W.; Sengonca, C. (1989). "Studies on the Biology and Behaviour of the Orb-Weaving Spider, Araniella Opistographa (Kulcz.) and the Crab Spider Philodromus Cespitum (Walck.), Common Spiders in Apple Orchards". Mitteilungen der Deutschen Gesellschaft für Allgemeine und Angewandte Entomologie. 6 (1–3): 158–163.
  16. 1 2 Sentenská, Lenka; Pekár, Stano; Uhl, Gabriele (August 2018). "Deposition, removal and production site of the amorphous mating plug in the spider Philodromus cespitum". The Science of Nature. 105 (7–8): 50. Bibcode:2018SciNa.105...50S. doi:10.1007/s00114-018-1575-8. PMID   30030630. S2CID   49896988.
  17. Sentenská, Lenka; Pekár, Stano (September 2019). "Silk‐ and volatile‐based male mate choice in the genital plug‐producing spider". Ethology. 125 (9): 620–627. doi:10.1111/eth.12913. S2CID   196683377.
  18. Kehlmaier, Christian; Michalko, Radek; Korenko, Stanislav (2012). "Ogcodes fumatus (Diptera: Acroceridae) Reared from Philodromus cespitum (Araneae: Philodromidae), and First Evidence of Wolbachia Alphaproteobacteria in Acroceridae". Annales Zoologici. 62 (2): 281–286. doi:10.3161/000345412x652819. S2CID   84282279.
  19. “Philodromus cespitum.” CABI- Invasive Species Compendium, Nov. 2019, www.cabi.org/isc/datasheet/40100.
  20. 1 2 Petcharad, Booppa; Košulič, Ondřej; Michalko, Radek (1 July 2018). "Insecticides alter prey choice of potential biocontrol agent Philodromus cespitum (Araneae, Philodromidae)". Chemosphere. 202: 491–497. Bibcode:2018Chmsp.202..491P. doi:10.1016/j.chemosphere.2018.03.134. PMID   29579684. S2CID   4774534.
  21. Řezáč, Milan, et al. “Contact Application of Neonicotinoids Suppresses the Predation Rate in Different Densities of Prey and Induces Paralysis of Common Farmland Spiders.” Sci Rep, vol. 5, no. 9, ser. 1, Apr. 2019. 1.