Nephila pilipes

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Nephila pilipes
Nephila pilipes, Bangunjiwo, Bantul 2015-09-19 04.jpg
N. pilipes photographed in Bantul, Indonesia
Ventral side of N. pilipes in the Philippines
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Arachnida
Order: Araneae
Suborder: Araneomorphae
Family: Nephilidae
Genus: Nephila
Species: N. pilipes
Binomial name
Nephila pilipes
(Fabricius, 1793)

Aranea longipes
Aranea maculata
Aranea pilipes
Aranea sebae
Epeira chrysogaster
Nephila maculata
Nephila fuscipes
Epeira fuscipes
Epeira doreyana
Epeira caliginosa
Nephila ornata
Epeira penicillum
Epeira harpyia
Nephila chrysogaster
Meta ornata
Nephila pecuniosa
Nephila aurosa
Nephila procera
Nephila sulphurosa
Nephila tenuipes
Nephila submaculata

The Northern Golden Orb Weaver or Giant Golden Orb Weaver[1] (Nephila pilipes) is a species of golden orb-web spider. It can be found in Japan, China, Vietnam, Cambodia, Taiwan, Malaysia, Singapore, Myanmar, Indonesia, Thailand, Laos, Philippines, Sri Lanka, India, and Papua New Guinea. It is commonly found in primary and secondary forests and gardens. Females are large and grow to a body size of 30–50 mm (overall size up to 20 cm), with males growing to 5–6 mm. It is one of the biggest spiders in the world.

The Nephila pilipes' golden web is vertical with a fine irregular mesh and not symmetrical, with the hub usually nearer the top.[1] Rather than egg sacks being hung in the web, a pit is dug which is then covered with plant debris or soil.

The first, second and fourth pairs of legs of juvenile females have dense hairy brushes, but as the spider matures these brushes disappear.


  • Nephila pilipes annulipes Thorell, 1881 – (Indonesia)
  • Nephila pilipes flavornata Merian, 1911 – (Sulawesi)
  • Nephila pilipes hasselti (Doleschall, 1859) – (Java)
  • Nephila pilipes jalorensis (Simon, 1901) – (India)
  • Nephila pilipes lauterbachi (Dahl, 1912) – (New Guinea)
  • Nephila pilipes malagassa (Strand, 1907) – (Madagascar)
  • Nephila pilipes novaeguineae (Strand, 1906) – (New Guinea)
  • Nephila pilipes piscatorum Vis, 1911 – (Queensland)
  • Nephila pilipes walckenaeri (Doleschall, 1857) – (Java)

Sexual Dimorphism[edit]

Nephila pilipes display sexual dimorphism, which is the concept that there is a distinct difference between the males and females of a species. This can be seen in Nephila pilipes where the female spiders are much larger than their male counterparts. [2] Males can be 4-10 times smaller than the females.[3]

Sexual dimorphism appears to be a shared feature among Nephila pilipes spiders of different populations, as examinations of populations in Southeast Asia, Australia, and Papua New Guinea have shown the trait to be a shared characteristic.[4] Although in these different populations the variations in the ratio of size from male to female did not change significantly, differences could be seen in other traits based on the environments in which the populations of spiders lived.[4]

Female Gigantism[edit]

One explanation for the dimorphism observed in the population is that female gigantism is being selected for as part of the female spider's response to the male's use of mating plugs.[5] With a mating plug, male spiders ensure that only the male who create the plug post coitus would be the father of the resulting offspring. Although in the species of N. pilipes, plugging does not seem to have an effect as females are still able to have successful matings even with multiple plugs.[5] The evolution of plugs occurred in earlier ancestral species and still persists along. These traits were then passed down to one of its decedents, the living species N. pilipes.[6] In this ancestral species, female gigantism was selected as a positive adaptation. In female spiders with larger bodies, the “embolic plugs” inserted in the N. pilipes females' genitalia become too thin to effectively seal the genitalia. [7] Additionally, female gigantism would have been important to the ancestral species at the time when mating plugs were still effective, as body size has been shown to increase fecundity.[8] By laying more eggs at a time, the ancestral females could have produced more offspring before they were plugged by a male. [4]

The mechanism used to explain female gigantism is molting, the shedding of the skin so that new skin can be formed after growth, which is done by females. While most spiders stop growing at the final molt to sexual maturity, N. pilipes females continue to molt after maturity, which contributes to the much larger size of females.[2] Females will stop molting, however, during times of high copulation where it may not be advantageous to continue to grow as sperm are fertilizing eggs.[2]

Male Dwarfism[edit]

An alternative reason for the displayed sexual dimorphism is that the dimorphism is due to male dwarfism instead of female giganticism. An explanation of how dwarfism was selected for is due to scramble competition. Through experimentation on N. pilipes spiders specifically, it is shown that the male spiders that were able to find the female spiders first often fertilized a greater percentage of her eggs than other males.[9] Also, because female N. pilipes spiders often did not remain on their webs, the smaller and more agile male spiders were able to reach them first, compared to the slower, larger males which often waited at the web of the female in advantageous spots. [9] This explanation means that smaller males had a greater fitness due to the behavior of the female spider to move around in maturity and when molting as the environmental conditions were such that females were more likely to move out from their webs than to constantly stay in them.[9]

Different views & aspects[edit]


  1. ^ a b Nephila pilipes,
  2. ^ a b c Kuntner, Matjaž; Zhang, Shichang; Gregorič, Matjaž; Li, Daiqin (2012). "Nephila Female Gigantism Attained through Post-maturity Molting". Journal of Arachnology 40.3: 345–347. 
  3. ^ S., Mark; D., Andrew; A., Mark (2007). "The systematics and biology of the spider genus Nephila (Araneae:Nephilidae) in the Australasian region". Invertebrate Systematics 21: 407–451. 
  4. ^ a b c Tso, I-Min; Shu-Ya, Chiang; Blackledge, Todd (2007). "Does The Giant Wood Spider Nephila Pilipes Respond To Prey Variation By Altering Web Or Silk Properties?.". Ethology 113: 324–333. 
  5. ^ a b Kuntner, Matjaž; Coddington, Jonathan; Schneider, Jutta (2009). "Intersexual Arms Race? Genital Coevolution In Nephilid Spiders (Araneae, Nephilidae)". Evolution 63: 1451–1463. 
  6. ^ Coddington, Jonathan; Hormiga, G; Scharff, N. (1997). "Giant female or dwarf male spiders?". Nature 385: 687–688. 
  7. ^ Kuntner, Matjaž.; Kralj-Fišer, S.; Schneider, Jutta; Li, Daiqin (2009). "Mate Plugging Via Genital Mutilation In Nephilid Spiders: An Evolutionary Hypothesis". Journal Of Zoology 277: 257–266. 
  8. ^ Legrand, Rebecca; Morse, Douglass (2000). "Factors driving extreme sexual size dimorphism of a sit-and-wait predator under low density". Biological Journal of the Linnean Society 71: 643–664. 
  9. ^ a b c Danielson-François, Anne; Hou, Chueh; Cole, Nina; Tso, I-Min (2012). "Scramble Competition For Moulting Females As A Driving Force For Extreme Male Dwarfism In Spiders". Animal Behavior 84: 937–945.