Home / Orb Weavers / Caerostris

Caerostris

The Caersotris, often called bark spiders, are part of the orb-weaver spider family. They call Madagascar and southeastern Africa their home. With nineteen known species as of April 2019, these spiders have a unique place in the spider world.

Scientific Classification

Caerostris Spider

Spiders Belonging To This Genus

  • Caerostris almae
  • Caerostris bojani
  • Caerostris corticosa
  • Caerostris cowani
  • Darwin’s Bark (Caerostris darwini)
  • Caerostris ecclesiigera
  • Caerostris extrusa
  • Caerostris hirsuta
  • Caerostris indica
  • Caerostris linnaeus
  • Caerostris mayottensis
  • Caerostris wallacei
  • Caerostris mitralis
  • Caerostris pero
  • Caerostris sexcuspidata
  • Caerostris sumatrana
  • Caerostris tinamaz
  • Caerostris vicina

Caerostris Sumatrana

Physical Description & Identification

Adults

  • Size:  The females are about 3 cm (1.18 inches) long, while the males are smaller with a body length of 1cm (0.39 inches).
  • Color: Most species of this genus are black with white abdominal hairs. Males mostly have a red or brown body.
  • Other Characteristics: The upper parts of their cephalothorax have a bumped appearance, mostly seen in females. Their legs also have a hairless appearance.

Eggs

The eggs are round and lay protected in an egg sac, hatching in 2 to 3 weeks.

Spiderlings

They remain with their mother for a while after being hatched and then disperse to dwell independently.

The Web

Their webs are strong and messy, resembling a spiral shape like most orb weaver species.

Bark Spider

Are Caerostris Spiders Venomous?

Yes, like most spiders, Caerostris spiders have venom. However, their venom is primarily used for immobilizing prey and is not known to be harmful to humans.

Can Caerostris Spiders Bite?

Caerostris spiders can bite if they feel threatened, but their bites are typically not dangerous to humans and are similar to a bee sting in pain level.

Ecological Importance and Behavior of Caerostris Spider

Caerostris spiders play a vital ecological role as biocontrol agents, regulating the population of small aquatic insects which they predominantly prey upon. Their behavior is adapted to their habitats near water bodies and swampy areas, where they can exploit the abundance of prey. The spiral webs serve not only as a hunting tool but also as a deterrent for potential predators.

Natural Predators: Despite their venomous defense, these spiders are not without predators. Birds, larger insects, and small mammals pose a threat, often preying on the spiders for sustenance.

Prey-Predator Dynamics: The Caerostris spiders’ interaction with their prey is a delicate dance of hunter and hunted. Their strong webs are strategic traps for unsuspecting insects, showcasing the intricate prey-predator dynamics within their habitat.

Relationship with Humans: Caerostris spiders have a benign relationship with humans, generally avoiding contact and residing in less-frequented areas. Their presence is often unnoticed, but they provide the service of controlling insect populations, a benefit that goes largely unrecognized.

Quick Facts

Lifespan Approximately 1 year
Distribution Madagascar and parts of southeastern Africa
Habitat Close to water bodies, swampy areas
Diet Small aquatic insects

Caerostris Habitat

Did You Know

  • Swedish arachnologist was the first to describe this genus in the year 1868.

In conclusion, Caerostris spiders are key ecological players, intricately balancing their ecosystems with quiet diligence.

The Caersotris, often called bark spiders, are part of the orb-weaver spider family. They call Madagascar and southeastern Africa their home. With nineteen known species as of April 2019, these spiders have a unique place in the spider world.

Caerostris Spider

Spiders Belonging To This Genus

  • Caerostris almae
  • Caerostris bojani
  • Caerostris corticosa
  • Caerostris cowani
  • Darwin’s Bark (Caerostris darwini)
  • Caerostris ecclesiigera
  • Caerostris extrusa
  • Caerostris hirsuta
  • Caerostris indica
  • Caerostris linnaeus
  • Caerostris mayottensis
  • Caerostris wallacei
  • Caerostris mitralis
  • Caerostris pero
  • Caerostris sexcuspidata
  • Caerostris sumatrana
  • Caerostris tinamaz
  • Caerostris vicina

Caerostris Sumatrana

Physical Description & Identification

Adults

  • Size:  The females are about 3 cm (1.18 inches) long, while the males are smaller with a body length of 1cm (0.39 inches).
  • Color: Most species of this genus are black with white abdominal hairs. Males mostly have a red or brown body.
  • Other Characteristics: The upper parts of their cephalothorax have a bumped appearance, mostly seen in females. Their legs also have a hairless appearance.

Eggs

The eggs are round and lay protected in an egg sac, hatching in 2 to 3 weeks.

Spiderlings

They remain with their mother for a while after being hatched and then disperse to dwell independently.

The Web

Their webs are strong and messy, resembling a spiral shape like most orb weaver species.

Bark Spider

Are Caerostris Spiders Venomous?

Yes, like most spiders, Caerostris spiders have venom. However, their venom is primarily used for immobilizing prey and is not known to be harmful to humans.

Can Caerostris Spiders Bite?

Caerostris spiders can bite if they feel threatened, but their bites are typically not dangerous to humans and are similar to a bee sting in pain level.

Ecological Importance and Behavior of Caerostris Spider

Caerostris spiders play a vital ecological role as biocontrol agents, regulating the population of small aquatic insects which they predominantly prey upon. Their behavior is adapted to their habitats near water bodies and swampy areas, where they can exploit the abundance of prey. The spiral webs serve not only as a hunting tool but also as a deterrent for potential predators.

Natural Predators: Despite their venomous defense, these spiders are not without predators. Birds, larger insects, and small mammals pose a threat, often preying on the spiders for sustenance.

Prey-Predator Dynamics: The Caerostris spiders’ interaction with their prey is a delicate dance of hunter and hunted. Their strong webs are strategic traps for unsuspecting insects, showcasing the intricate prey-predator dynamics within their habitat.

Relationship with Humans: Caerostris spiders have a benign relationship with humans, generally avoiding contact and residing in less-frequented areas. Their presence is often unnoticed, but they provide the service of controlling insect populations, a benefit that goes largely unrecognized.

Quick Facts

Lifespan Approximately 1 year
Distribution Madagascar and parts of southeastern Africa
Habitat Close to water bodies, swampy areas
Diet Small aquatic insects

Caerostris Habitat

Did You Know

  • Swedish arachnologist was the first to describe this genus in the year 1868.

In conclusion, Caerostris spiders are key ecological players, intricately balancing their ecosystems with quiet diligence.