Image Credit: Image copyright www.InsectIdentification.org; No Reproduction Permitted
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Image Credit: Image copyright www.InsectIdentification.org; No Reproduction Permitted
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Image Credit: Heather B.
The thorny spikes and bumps on the abdomen of the dark Spined Micrathena Spider are not typically found on Orbweavers.
The pointed ridges on the abdomen of the female spider are believed to render less appealing to eat to predators. The spines presumably hurt the mouth of the predator, making the Spined Micrathena Spider not worth the meal. The black, brown, and white coloration may act as camouflage since this species resides in dense forests where specks of light may be all that gets through to the forest floor. That said, colors vary slightly per individual. Some are very brown; others are only black and white.
The male lacks the sharp ridges and may be more white or more black in color. Its waist is more narrow than a female's. Females sit in the center of the web, waiting for insects to get trapped by the silk threads. As an Orbweaver Spider, the web is built in a circle or spiral shape. Orbweavers tend to rebuild their webs every day. This species is most active in the summer and can be found in dense woods or forests.
Taxonomic Hierarchy
Kingdom:Animalia
Phylum:Arthropoda
Class:Arachnida
Order:Araneae
Family:Araneidae
Genus:Micrathena
Species:gracilis
Identifying Information
Scientific Name: Micrathena gracilis
Category:
Spider
Size (Adult; Length): 4mm to 10mm (0.16in to 0.39in)
Note: An insect's reach is not limited by lines drawn on a map and therefore species may appear in areas, regions and/or states beyond those listed above as they are driven by environmental factors (such as climate change), available food supplies and mating patterns. Grayed-out selections indicate that the subject in question has not been reported in that particular territory. U.S. states and Canadian provinces / territories are clickable to their respective bug listings.
Spider Anatomy
1
Legs: Spiders have four pairs of legs and these are attached to the cephalothorax.
2
Pedipalps: Small appendages near the mouth used as taste and smell organs.
3
Cephalothorax: Contains eyes, head, mouthparts, and legs.
4
Abdomen: Contains various organs related to digestion, reproduction, and web-making.
5
Spinnerets: Used in the production of spider silk for fashioning webs or catching prey.
NOTE: Unlike insects, spiders have both an endoskeleton (internal) and exoskeleton (external).
Colors: black; white; yellow; brown
