Jumping creature spins ‘sheets of web’ and tucks self in at night. It’s a new species

While sorting through leaves littering a forest floor in the Democratic Republic of Congo, researchers spotted something peculiar on the underside of a leaf: a “small” sheet of web with an eight-legged creature tucked inside.

Scientists were exploring Salonga National Park, searching for salticids, a type of jumping spider, according to a study published Jan. 11 in the journal Zootaxa. Between November and December 2022, they searched the forest floor, sometimes using traps and sieves, to sort through leaf litter and debris.

That’s when they came across eight specimens with distinct genitalia and other features and discovered three new six-eyed species: Thiratoscirtus iyomii, Thiratoscirtus kalisia and Thiratoscirtus khonvoum.

Thiratoscirtines are a type of “leaf-litter dwelling spiders” found in Central and West Africa forests, study co-author Brogan Pett told McClatchy News in a Jan. 16 email. They are particularly abundant in rainforests.

Because the creatures live in “incredibly difficult to access locations” there is limited knowledge about their behavior in the wild, according to Pett.

“Little is known of their specific ecology although they are certainly day active and will likely eat the majority of invertebrates of a similar size, including flying, ground active and fossorial ones,” Pett said. “As regards webbing for nesting, they likely make small sheets of web on the underside of leaves and “tuck themselves in” at night (this is how several were caught).”

The Democratic Republic of the Congo is in central Africa and borders nine countries: Angola, Burundi, the Central African Republic, the Republic of the Congo, South Sudan, Rwanda, Tanzania, Uganda and Zambia. Salonga National Park is in the center of the country.

Thiratoscirtus iyomii

The team examined four specimens of Thiratoscirtus iyomii, one male and three females, to diagnose the new species, according to the study.

Researchers said male spiders have a brown body covered with five “distinctive” spots of white bristles forming a “wide U-shape” and some fluorescent patches. The spider’s chelicerae, which are like its jaws, are orange-brown and teeth, including a “very large” and “tusk-like” tooth. They have brown legs and a beige abdomen.

Female spiders have similar coloring to males, but their legs are “pale yellowish-brown” and their abdomen is “streaky brown,” scientists said. Females lack some of the same teeth as males.

The species was partially distinguished by its genitalia, according to experts. Males have a “broad and long” embolus — which is used to transmit sperm to a mate during reproduction — and females have a “small, spherical” spermatheca — which stores sperm from males.

Thiratoscirtus iyomii was named after a “great and powerful” war chief, Iyomi, who was capable of miracles, researchers said.

Thiratoscirtus kalisia

Only one female specimen of Thiratoscirtus kalisia was collected, researchers said.

Scientists said the spider was distinguished as a new species by her unique genitalia, specifically her unusual and “very large” epigynal region — which is a female spider’s external genitals.

The spiders have a “deep dark brown” body with a “very dark patch” around their eyes, experts said. They have some fluroescence on their bodies, and their sternum is “deep red brown.”

Their chelicerae are dark brown with three teeth, and their legs are a darker brown, according to the study. Their abdomen is pale brown with “alternating bands of light and dark patches.”

The new species was named after “Kalisia,” a “creator god and guardian of hunters and dense forests” in the DRC, researchers said.

Thiratoscirtus khonvoum

Researchers collected and examined three female specimens to identify Thiratoscirtus khonvoum as a new species.

Like the other two species, Thiratoscirtus khonvoum was also distinguished by its genitals, particularly its “very long” fertilization duct” and “the very large anterior coils” of its copulatory duct, which put sperm into the spermatheca.

These spiders have a “dark orangish brown” body with a light orange band and “small patches” of fluorescence, scientists said. Their chelicerae are “deep red,” and their legs are light brown to pale cream.

The new species was named after the supreme god and creator “Khonvoum” in Bambuti Pygmy mythology, experts said.

This story was originally published January 17, 2024 at 10:17 AM with the headline "Jumping creature spins ‘sheets of web’ and tucks self in at night. It’s a new species."

Moira Ritter

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Moira Ritter covers real-time news for McClatchy. She is a graduate of Georgetown University where she studied government, journalism and German. Previously, she reported for CNN Business.