Spitting spider
The spitting spider, scientifically known as *Scytodes thoracica*, is a small arachnid belonging to the family Scytodidae, with a size ranging from 3 to 6 millimeters. Commonly found in Europe and North America, this spider is notable for its unique hunting technique, where it spits sticky silk to ensnare prey such as silverfish, moths, flies, and mosquitoes. The silk is ejected in a zig-zag pattern, which effectively immobilizes the prey, allowing the spitting spider to bite and consume it.
Characteristically, the spitting spider has a yellow body adorned with tiny black dots, eight legs, and six eyes, with a pair of short appendages called palps used for grasping food. It walks on long legs that extend beneath its body to protect a sac that stores its silk. Reproductive behavior occurs in the spring, with the male fertilizing the female directly, leading to the hatching of eggs in two to three weeks. Young spitting spiders remain with their mother until they can fend for themselves, and they typically reach adulthood after five to seven molts, with a lifespan of about 2.5 to 4 years. The spitting spider's distinctive hunting method and adaptive features make it a fascinating subject of study within the arachnid world.
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Spitting spider
The spitting spider, Scytodes thoracicia, is among the most common of the 250 spitting spider species. Like other spitting spiders, this arachnid can spit sticky silk to trap its prey. The silk lands on the prey in a zig-zag pattern trapping the creature so the spitting spider can focus on biting it.
Kingdom: Animalia
Phylum: Arthropoda
Class: Arachnida
Order: Araneae
Family: Scytodidae
Genus: Scytodes
Species: Thoracica
The spitting spider grows to 3/20 to 1/4 inch (3 to 6 millimeters). Its body is divided into two main partsthe cephalothorax and the abdomen. The cephalothorax, also called the prosoma, contains the spitting spider’s head and thorax, or mid-body section. A domed carapace, or hard, arched shell, protects this portion. The eight legs of the spitting spider are attached to the creature's cephalothorax. The abdomen of the spitting spider is the creature's lower-body section. This portion contains most internal organs and may be called the opisthosoma. Between the cephalothorax and the abdomen is a narrow tube called a pedicel. The body of this spitting spider is yellow with many tiny black dots and specks.
Like other spiders, the spitting spider has eight legs and six eyes. It also has a front pair of short appendages called palps. These appendages are used for grasping and tearing prey. This is especially helpful when the spitting spider removes a victim from its silken trap.
The spitting spider was called spitting for its practice of spitting silken strands over its prey. The sticky, glue-like silk of the spitting spider is held in a protective sac beneath the creature's abdomen. Because of this bulging sac, the spitting spider walks with its legs extended directly beneath its body like stilts. This protects the sac from the surface of the ground.
When the spitting spider sees a prospective prey it spits two strands of sticky silk. As it spits, it moves its body from side to side causing the strands to land in a zig-zag pattern over the prey. This pattern, along with the sticky nature of the strands, prevents the prey from escaping. While it lies beneath the sticky strands, the spitting spider prepares to bite the prey. Eventually, the spitting spider holds the prey with its palps and feeds. Spitting spiders eat silverfish, moths, flies, and mosquitos.
Spitting spiders are found in well-vegetated areas such as grasslands and forests. This small silk-spitting spider is common throughout Europe and North America.
Generally, the spitting spider mates in the spring by direct fertilization. This means the male releases his sperm directly into the female's body. The sperm is used to fertilize the female's eggs. Shortly after mating, the female lays her eggs. After two to three weeks, the young hatch. The hatchlings stay with their mother until they can survive on their own. They are adults after they molt five to seven times.
The spitting spider has an average lifespan of 2 1/2 to 4 years.
Bibliography
Baker, Nick. "Spitting Spider Guide: Where They Live, How They Kill Their Prey - And Why They’re Called Spitting Spiders." Discover Wildlife, 16 Feb. 2023, www.discoverwildlife.com/animal-facts/insects-invertebrates/spitting-spider-guide. Accessed 15 May 2024.
Brand, Jacqueline. "Scytodes Thoracica." Animal Diversity Web, animaldiversity.org/accounts/Scytodes‗thoracica. Accessed 15 May 2024.
"Spitting Spiders - Nature's Strangest Hunters." University of Queensland, imb.uq.edu.au/article/2017/11/spitting-spiders-natures-strangest-hunters. Accessed 15 May 2024.
"Summary for Scytodes Thoracica (Araneae)." British Arachnological Society, srs.britishspiders.org.uk/portal.php/p/Summary/s/Scytodes+thoracica. Accessed 15 May 2024.