Aretaon asperrimus, commonly known as the Thorny Stick Insect or Sabah Thorny Stick Insect, is a flightless species of stick insect native to the island of Borneo (specifically Sabah) and parts of the Philippines. 
 
Physical Characteristics
Appearance: Both sexes are dark brown, wingless, and covered in small, harmless "thorns" or spikes across their heads, bodies, and legs. They have mottled yellow and brown eyes.
Sexual Dimorphism:
Females: Larger and bulkier, reaching lengths of 8–9 cm. They possess a prominent ovipositor at the end of the abdomen for burying eggs in soil.
Males: Smaller and more slender, typically 5–6 cm long.
Mating Behavior: Males are frequently seen being carried on the backs of females for several days before and after mating. 
 
Habitat and Diet
Native Range: Primarily found in the tropical rainforests of Sabah, Borneo (e.g., Mount Kinabalu), and the Philippine islands of Palawan and Luzon.
Natural Diet: Herbivorous nocturnal feeders that consume a variety of foliage including Bramble (Blackberry), Raspberry, Rose, Ivy, and Oak. 
 
Captive Care
This species is popular among hobbyists as a "beginner" stick insect due to its docile nature and ease of care. 
Environment: Prefers temperatures between 20–24°C and high humidity (60–80%), requiring regular misting.
Housing: Should include bark pieces for hiding during the day. A dish of moist soil or substrate is essential for females to lay their eggs.
Life Cycle: Eggs hatch in 3–4 months on average, and the total lifespan is approximately 9–12 months.