Marbled Orb-weaver (Araneus marmoreus)

The marbled orb-weaver, belonging to the class Arachnida, is one of the good-looking spiders. Their abdomen has several marble-like patterns which are the reason behind the name.

Physical Description and Identification

Adults

Size: Females are 0.35-0.8 in (9-20 mm) while males are around 0.19-0.35 in (5-9 mm).

Scientific Classification

• Family: Araneidae
• Genus: Araneus
• Scientific name: Araneus marmoreus

Color: Orange or light brown legs and carapaces along with black or white stripes at the leg end. The abdomen is orange, yellow or white having white, grey or black marble-like patterns.

Other Characteristic Features: The abdomen is oval and their tibial spines are of two types.

Eggs

Around hundred eggs are released inside a fluffy and silky flat sphere-shaped egg cocoon or sac in October. All eggs are orange.

Spiderlings

Spiderlings emerge from the eggs in the spring and they live on the silk of the egg sacs. Within the July, they become fully adult.

The Web

The vertically oriented web usually has a signal thread which vibrates when a prey is captured and the spider then come out to devour it.

Are Marbled Orb-weaver Poisonous

Its venom is only effective on its preys to paralyze them. If it bites humans there is just a mark with no such serious injury.

Quick Facts
Also known as	Pumpkin spider
Distribution	Texas, North Dakota, northern Rockies, Alaska and all over in Canada
Habitat	Grasses, shrubs, woods near water bodies like ponds, streams, creeks
Web Type	Orb web
Diet	Small insects
Mode of Communication	Through pheromones, touch, and vibrations
Lifespan	6 months
Predators	blue mud daubers, spider wasps, white-trimmed black wasp, organ pipe mud daubers
IUCN Conservation Status	Not listed

Did You Know

• Male marbled orb-weavers are polygamous but females mate only once in their lives.
• Sometimes, both the male and female die after the mating.
• After making the web, they hide in a silk retreat.
• The male strokes the body of a female with his legs during the courtship.

Image Credits: 2.bp.blogspot.com, Minnesotaseasons.com, C1.staticflickr.com, Mrhyker.tripod.com, Farm4.static.flickr.com,
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