Peacock spider characteristics, habitat, reproduction, behavior

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Basil Manning

The peacock spider (Maratus volans) is a small arachnid representative of the Salticidae family. This family is the most diverse at the level of species and genera in the world. The gender Maratus currently has approximately 90 species, almost all distributed in Australia, except for M. furvus which is native to China.

The taxonomic locations of many of these species, and the relationships between them, are not yet well understood. Currently the position of the genus and several species are discussed, since there are several very similar genera such as Saitis.

Peacock spider (Maratus volans) displaying abdomen By Jurgen Otto [CC BY-SA 2.0 (https://creativecommons.org/licenses/by-sa/2.0)]

Jumping spiders are generally visual specialists among arthropods. Thus, it is not surprising that most males of the multiple species of the Salticidae family make elaborate displays during courtship..

The vibrations produced by the males, which are transmitted through the substrate, plus the elaboration of complex visual screens, work very well during courtship. Sexual selection plays an intense role in the evolution of these complex characteristics.

The spiders of the Salticidae family usually present an important sexual dimorphism, the males being more ornate than the females. However, Maratus volans represents an exceptional case of dimorphism within the family. Males tend to have very colorful abdomens and an elongated and ornate third pair of legs, while females have cryptic colorations with the environment..

Initially, it was believed that the lateral folds of the abdomen had a functionality during the jumps of these little spiders. On several occasions, some researchers pointed out that the ailerons of the abdomen could influence the time that these spiders are in the air after each jump.

However, this has not been proven so far. One of the species with the greatest similarity in appearance and reproductive behavior is Maratus pardus.

Article index

  • 1 General characteristics
    • 1.1 Coloring
  • 2 Habitat and distribution
  • 3 Playback
    • 3.1 Courtship
  • 4 Nutrition
  • 5 Behavior
    • 5.1 Courtship sequence
    • 5.2 Flickering of the pedipalps
    • 5.3 Opistosome movement
    • 5.4 Raising the third pair of legs
    • 5.5 Opistosome fin unfolding
    • 5.6 Dance
    • 5.7 Pre-copula deployment
  • 6 References

General characteristics

These spiders are about 5 millimeters long. They are of an ordinary morphology, similar to most of the species of the Salticidae family. The eyes are in a typical position, almost forming a square. The anterior middle pair of eyes is larger and visually developed.

The lengths of the first, second, and fourth pair of legs are similar. The third pair of legs of the male Maratus volans they are more elongated than the rest of the ambulatory legs. Additionally, they present ornaments that play a fundamental role during courtship..

Specifically, the metatarsal of the third pair of legs is covered by a dense tuft of black setae and a group of comparatively thick white setae that adorn the tarsi..

The abdomen has an elongated and oval shape, being flattened dorsoventrally. The dorsal region is provided with an epidermis that continues to the sides. These epidermal folds exceed the normal width of the abdomen and are semioval in shape. These fold up on the sides and even fold under the abdomen.

These folds can expand to their full width during courtship of males. Females are devoid of these folds in the abdomen and tend to have it more robust. In the following video you can see what the courtship of a spider of this species is like:

Coloration

Both females and males are clearly distinguishable. The males are usually very colorful while the females have a dark brown coloration. The coloration of the males is difficult to describe due to their great beauty.

The thoracic region and the lateral regions of the cephalothorax are black, the latter, with the margins covered by white hairs. The dorsal region is much more colorful. The cephalothorax has an alternating banded coloration between the eyes, with greyish green and bright red bands.

The legs, with the exception of the third pair, have a mixture of whitish and brown hairs in the same way as the pedipalps and the basal segments of the chelicerae.

The entire dorsal surface of the abdomen is covered by very short hairs like scales. The latter have a great variety of tones that give the abdomen its particular beauty. The pattern on the abdomen closely resembles a Salticidae spider of the same genus.

The central and anterior portion is striped longitudinally, alternating scarlet red and blues that reflect metallic tones. The posterior region has transverse bands of similar colors. The lateral fins are of a soft yellowish color, tinged with olive green, each one being marked with two grayish-green stripes.

Computerized scheme of the coloring pattern of Maratus volans By KDS444 [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)]

Habitat and distribution

The peacock spider, Maratus volans, like the vast majority of representatives of the genus, it is endemic to Australia.

This species has been recorded mainly from locations near the east coast of Australia in Queensland, New South Wales, Victoria and around Sydney in the Ku-ring-gai Chase National Park and Cowan Field Station in the Muogamarra Reserve.

In other towns near Queensland, especially in the southeast, they have also reported the presence of M. volans. Other locations are Seal Rocks, on the coast, about 80 km north-east of Newcastle, and Coolah Tops, an inland site about 200 km north-west of Newcastle..

It has also been recently photographed in Warburton, 70 km east of Melbourne, and near Brisbane.

These spiders are found in dry environments near the coast and more tropical environments. They use microhabitats close to the ground and can also be located on shrubby vegetation and in the lower areas of herbaceous plants..

The females of M. volans They are usually located in areas such as litter on dry branches and fallen on the ground as a mechanism of crypsis or mimicry.

Reproduction

Peacock spiders are more active and easier to locate in the reproductive season that spans the southern spring. Mature males emerge from August and persist until December. The females appear later and survive longer than the males, hiding in December to lay their eggs..

Because M. volans has a wide geographic range in Australia and occupies varied environments, breeding periods may vary slightly.

In the absence of visual stimuli, males can detect silk threads left by the female in their wake. These threads are impregnated with pheromones that indicate their reproductive status.

The peacock spider is perhaps the arachnid with the most elaborate courtship behavior. These jumping spiders employ multimodal flirting behavior that encompasses a complex mix of tactile, vibratory and visual cues..

This facilitates and makes the transmission of information to females complex, sending multiple messages that can reflect the same information. Males with this elaborate courtship emphasize different aspects of male morphology..

Courtship

During courtship, a peacock spider displays a series of very colorful and shiny opisthosomal fins or folds that are usually kept folded on the abdomen. All this very elaborate structure resembles the caudal fan of a peacock, which is why they are called peacock spiders..

The abdomen shakes in a very elaborate routine in which the third pair of legs also participates, presenting a series of ornaments as ornaments.

Courtship time can range from six to 51 minutes. The sequence of behavior of the males presents variations that are attributable to each individual.

Nutrition

The activity of these spiders is predominantly diurnal. The food of these small spiders covers a wide range of insects and even other arachnids. These include a great variety of species of flies, crickets, Hemiptera, Lepidoptera, Homoptera, Hymenoptera, among others..

In general, these small and agile spiders can locate potential prey at a distance that can exceed 20 centimeters. The latter is quite admirable for a spider that barely reaches 5 millimeters in length, also enjoying one of the best views among arachnids..

Females with eggs can capture males for reproductive purposes, so cannibalism can be prevalent within the species. Additionally, females after mating show a greater degree of aggressiveness against males, which is why they tend to flee quickly after copulation..

Behaviour

Courtship sequence

The entire act of courtship is accompanied by vibrational signals caused by the movement of the opistosome. The vibrations are precursors of any movement that the male makes.

The vibrations can come from the stridulation caused between the movement of the opistosoma and the cephalothorax. In addition, they can originate through the vibrations of the abdomen that are transmitted to the substrate through the legs.

Pedipalps blinking

Courtship initially begins with blinking movements of the pedipalps. These movements occur intermittently throughout the courtship act and can also be accompanied by other behaviors of the male..

They have a fundamental function when the female is away from the male or is not oriented directly towards him.

Opistosome movement

After the pedipalpal movement, an act of wiggling the abdomen begins in various directions regardless of the expansion and retraction of the characteristic folds in the opisthosoma..

The lifting of the third pair of legs, which presents modifications for courtship, occurs simultaneously with the lifting of the opisthosoma and the unfolding of its flaps. The lifting of the legs can precede the lifting of the abdomen, a fact that occurs if the male is away from the female.

Opistosome wiggling occurs when males approach a female from a distance or between episodes of third pair of legs agitation.

Raising the third pair of legs

The third pair of legs moves in an undulating manner when the male performs lateral marches. This movement occurs almost continuously. Occurs once he comes into frontal visual contact with the female.

Fin display of opistosome

Fan-shaped opistosome movement, with extended folds, occurs when males are close enough to females.

The abdomen moves back and forth laterally like a metronome, at highly variable speeds. Most of the time the opistosome moves in sync with the third pair of legs.

Dance

When the opisthosome is oriented vertically, the lateral folds extend and retract several times in sequence. While the latter occurs, the third pair of legs remains in a vertical position. This occurs periodically when the male makes small pauses in his movements of the deployment of the opistosoma..

Pre-copulation deployment

This display occurs immediately after the courtship dance and constitutes the final act before copulation. The third pair of legs rotates forward and the cephalothorax is raised on the first pair of legs. Simultaneously, the opistosome folds retract and the abdomen returns to its resting position very close to the substrate.

During this period, spaced episodes of oscillations of the opistosome occur in the form of pulses that correspond to vibrations. The descent of the third pair of legs to the ground also occurs, together with the second pair of legs..

The first legs approach the female's cephalothorax while the male comes into contact with it, while the third pair of legs is located on the ground in an inverted v shape. Then, the male is located on the female and copulation occurs.

References

  1. Girard, M. B., Kasumovic, M. M., & Elias, D. O. (2011). Multi-modal courtship in the peacock spider, Maratus volans (OP-Cambridge, 1874). PLoS One, 6(9), e25390.
  2. Girard, M. B., & Endler, J. A. (2014). Peacock spiders. Current Biology, 24(13), R588-R590.
  3. Girard, M. B., Elias, D. O., & Kasumovic, M. M. (2015). Female preference for multi-modal courtship: multiple signals are important for male mating success in peacock spiders. Proceedings of the Royal Society B: Biological Sciences, 282(1820), 20152222.
  4. Girard, M. B. (2017). Sexual Selection and Signal Evolution: Diversification of Peacock Spiders (Genus: Maratus) (Doctoral dissertation, UC Berkeley).
  5. Laidre, M. E., & Johnstone, R. A. (2013). Animal signals. Current Biology, 2. 3(18), R829-R833.
  6. Maddison, W. P. (2015). A phylogenetic classification of jumping spiders (Araneae: Salticidae). Journal of Arachnology, 231-292.
  7. Metzner, H. (2019): Jumping spiders (Arachnida: Araneae: Salticidae) of the world. Accessed 14 December 2019. Online at https://www.jumping-spiders.com
  8. Otto, J. C., & Hill, D. E. (2011). An illustrated review of the known peacock spiders of the genus Maratus from Australia, with description of a new species (Araneae: Salticidae: Euophryinae). Peckhamia, 96(1), 1-27.
  9. Otto, J. C., & Hill, D. E. (2014). Description of a new peacock spider from Cape Le Grand, Western Australia, with observations on display by males and females and comparative notes on the related Maratus volans (Araneae: Salticidae: Euophryinae: Maratus). Peckhamia, 114, 1-38.

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