The spider commonly known as the Banana Spider in North America is the Golden Silk Orb-Weaver (Trichonephila clavipes). This imposing arachnid is often seen in the southeastern United States. It is famous for the large, intricate webs it weaves, which can span several feet and shimmer with a distinctive golden hue. The life cycle of the Golden Silk Orb-Weaver is tightly synchronized with the seasons, meaning its entire existence is typically completed within a single year.
Identifying the Banana Spider
The American “Banana Spider” is the Golden Silk Orb-Weaver, one of the largest non-tarantula-like spiders in the region. The female is the most recognizable, featuring a cylindrical, elongated abdomen that can be dull orange to tan with yellow spots. This shape contributes to the common name’s reference to a banana. Females are significantly larger than males, with a body length ranging from 24 to 40 millimeters, excluding their long, banded legs. A distinguishing feature is the presence of feathery tufts of hair, sometimes called gaiters, on the tibial segments of the first, second, and fourth pairs of legs. The species is primarily found in warm, humid regions, extending from the southeastern United States through Central America and into South America.
Lifespan and Seasonal Cycle
The lifespan of the Golden Silk Orb-Weaver is relatively short, constrained by the temperate growing season, with the entire life cycle generally taking less than a year. The species is univoltine, meaning it completes only one generation annually. Spiderlings hatch in the spring and spend the summer growing rapidly through several molting stages. Adult males are typically present from July to September, while the larger females usually mature later, often by August or September.
The adult stage is the shortest part of the spider’s life, especially for the male. Adult females may live for a few months, remaining active late into the fall to ensure reproduction. Adult males, which are small, have a much shorter life expectancy, often living only two to three weeks after reaching maturity. The life cycle ends with the first hard frost or prolonged cold weather, which the adult spiders cannot survive.
The Stages of Development
The life cycle begins with the egg sac, which the female produces in late summer or fall, often attached to leaves or branches. Each sac is a large, silken ball, about one inch in diameter, containing several hundred eggs protected by a basket of curly yellow silk. The spiderlings hatch inside this protective covering but remain dormant within the sac throughout the winter, a period of diapause.
When the weather warms in spring, the tiny spiderlings emerge and disperse. They often use a method called ballooning, floating on wind currents using strands of silk. Throughout the summer, the young spiders grow by molting, shedding their rigid external skeleton multiple times to increase in size. This growth continues until they reach their final adult size in late summer. For the female, the end of her life is marked by the production of her egg sacs, while the male’s short adult life often concludes shortly after mating, sometimes due to the female’s aggression.