Tarantulas generally live underground or in tree bark crevices. However, the tarantula species Taksinus bambus chooses a different location. The animal prefers to reside inside the cavity of bamboo stems.
Taksinus bambus was first discovered in the mountainous areas of Northern Thailand in 2020. The mountain areas are overgrown with Asian bamboo trees from the genus Gigantochloa.
The cool and humid air temperatures in the mountainous region provide a suitable environment for the bamboo tarantula to thrive.
The species name of the tarantula carries a meaning closely connected to Thailand.
The genus name Taksinus was given to honor King Taksin the Great of Thailand. Meanwhile, the species name bambus was derived directly from the name of the bamboo plant where it resides.
Utilizing Abandoned Insect Holes
Despite making bamboo its home, the tarantula does not build its nest from scratch. The bamboo stem has a very hard outer layer.
The tarantula's jaws are not designed to bore through such a hard structure. Because it cannot create an entrance hole on its own, this tarantula utilizes abandoned holes left by other insects.
Tarantulas primarily gain access through bamboo stems bored by beetles, carpenter bees, and caterpillars.
The sizes of the entrance holes left by the insects vary. The width of the openings generally ranges from two to three centimeters.
The size of the opening is suitable for the tarantula's body to pass through. The tarantula searches for bamboo stems that already have open access holes.
The chosen entrance hole is usually located at the node section of the bamboo. The node section provides a fairly spacious inner cavity.
The insects that made the holes have usually left the bamboo. As a result, the tarantula can occupy the empty cavity without needing to fight for space.
Construction of the Silk Tube Nest
After occupying the empty bamboo cavity, the tarantula begins to secure its dwelling. The animal secretes silk threads from its body organs. The silk is woven gradually onto the inner walls of the bamboo. The silk layer covers the entire hard surface inside the bamboo stem cavity.
The woven silk forms a nest structure resembling a tube. The silk tube nest functions as the tarantula's primary protective shelter.
The silk layer helps maintain stable humidity and air temperature levels inside the bamboo cavity. In addition, the silk nest provides protection against attacks from other predators.
The fine texture of the silk threads facilitates the tarantula's movement inside the cavity. The slippery bamboo wall is no longer an obstacle. The female tarantula places her egg sac inside the silk nest.
The tarantula eggs receive multi-layered protection from the bamboo wall and the silk web. The entrance of the nest is also covered with a thin sheet of silk.
The sheet serves to detect vibrations from passing prey. The tarantula emerges briefly to capture the prey and then retreats back into the silk tube.
Differences in Body Size
In addition to its unique lifestyle, Taksinus bambus displays distinct physical differences between males and females.
Male tarantulas have a more compact body form. The body length of the male stands at 2.6 centimeters, with a carapace area measuring around 1.1 centimeters. The males emerge from the bamboo nest when entering the reproductive period.
Meanwhile, female specimens possess a larger body size. The body length of the female reaches 3.5 centimeters, with a carapace area measuring around 1.4 centimeters.
The larger body size functions to accommodate the reproductive organs. Females tend to stay within a single bamboo cavity throughout their lives.
Differences are also evident in the leg length proportions of both sexes. Males feature longer front leg pairs compared to their hind legs.
The first leg of the male measures around 4.6 centimeters, whereas the fourth leg has a length of 4.5 centimeters. Conversely, the female's hind leg pair is longer than the front leg pair. The fourth leg of the female measures around 3.5 centimeters, while her first leg measures approximately 3.2 centimeters.
Reference:
Chomphuphuang, N., Sippawat, J., Sripreechasak, P., & Songsangchote, C. (2022). A new genus and species of bamboo-dwelling tarantula from Thailand (Araneae, Theraphosidae, Ornithoctoninae). ZooKeys, 1080, 1–19. https://doi.org/10.3897/zookeys.1080.76892
