For the first time scientists found a spider taking refuge underwater for more than 30 minutes (Pic. Courtesy sciencealert.com)
When an amphibious creature or a frog escapes into water to avoid danger or predation, it is accepted as normal. Yet when this tactic is adopted by a spider, it will make observers sit up, especially scientists connected with the study of arachnids as per a report in sciencealert.com.
The recently found species, named Trechalea extensa, provided a glimpse of its ability to stay underwater much to the surprise of the researchers. It was shocking for them since for any other member of this species being submerged is highly risky and inviting trouble. To begin with there is lack of air, loss of heat, nothing to eat and moreover, it is an invitation to unknown and diverse predators.
Scientists, as per a new study, to their amazement found this tropical spider in a stream in Costa Rica which stayed submerged underwater for 32 minutes at a stretch!
Commenting on this, the study’s lead author Lindsey Swierk said: "For a lot of species, getting wet and cold is almost as risky to survival as dealing with their predators to begin with. Trechalea spiders weren't previously known to hide underwater from threats – and certainly not for so long."
Swierk is a biologist at Binghamton University.
It was in 2019 in the month of July that the scientists spied a T. extensa sitting on a boulder which was near a small stream – a part of the Java River. The stream is located at the Las Cruces Biological Station in Costa Rica’s Puntarenas Province.
The researchers attempted to catch the spider but it took off over the surface of the water. When they continued to chase the animal, it flummoxed them. Going down the rock it went inside the water. It stayed under 10 inches of water for more than half an hour while the researchers sat bewildered at its behaviour.
It was finally caught when it came out but the scientists had filmed and clicked the spider underwater.
Though what they observed is essentially based on the study of just one spider and that too in just one incident, the researchers suggested that the secret behind this ability of the spider to stay underwater is due a “film” of air that encircles or surrounds its body. The spider’s hair which covers it are able to repel the water so much that they create a barrier or shield out of air which safeguards it from all the dangers of the water.
Sharing details on this Swierk said: "The film of air surrounding the spider when it is underwater appears to be held in place by hydrophobic hairs covering the spider's entire body surface. It's so complete that the spider almost looks like it's been dipped in silver. The film of air might serve to keep the respiratory openings away from water, since these spiders are air-breathing. The film of air might also help to minimize thermal loss to the cold stream water that the spider submerges itself in."
Details of the research on this interesting species were published in Ethology.