Cupiennius salei is a large spider with distinct sexual dimorphism.
The females are relatively larger than the males, measuring up to 3.5 cm in body length, with a 10 cm legspan.
The dorsal side of the body is chocolate-brown with small, lighter spots on the abdomen and many darker longitudinal stripes, particularly on the carapace.
The ventral side is red-orange with thick black central region under the abdomen.
Males measure up to 2.5 cm long and have very long and thin legs.
The males are much lighter in colour than the females.
They are distinct, with conspicuous palpal bulbs.

Cupiennius salei have one pair of principal eyes and three pairs of secondary eyes located on the prosoma (the anterior end of the head) and they are colour blind.
Being adapted to nocturnality, their visual capability is reduced and they rely on their tactile sensation to detect movements or vibrations in their environment.

Under laboratory conditions, females make cocoons every three to four weeks, each containing up to 1,500 embryos.
The embryo is typically 1.3 mm in diameter.
The complete life cycle takes between 9 and 12 months from fertilized egg to mature adult.
After hatching from the cocoon, the larvae start feeding.
Generally they are fed first with fruit flies and later with crickets.
They become reproductively mature after the final moult.
Cupiennius salei is a large spider with distinct sexual dimorphism. The females are relatively larger than the males, measuring up to 3.5 cm in body length, with a 10 cm legspan. The dorsal side of the body is chocolate-brown with small, lighter spots on the abdomen and many darker longitudinal stripes, particularly on the carapace. The ventral side is red-orange with thick black central region under the abdomen. Males measure up to 2.5 cm long and have very long and thin legs. The males are much lighter in colour than the females. They are distinct, with conspicuous palpal bulbs.
Cupiennius salei have one pair of principal eyes and three pairs of secondary eyes located on the prosoma (the anterior end of the head) and they are colour blind. Being adapted to nocturnality, their visual capability is reduced and they rely on their tactile sensation to detect movements or vibrations in their environment.
Under laboratory conditions, females make cocoons every three to four weeks, each containing up to 1,500 embryos. The embryo is typically 1.3 mm in diameter. The complete life cycle takes between 9 and 12 months from fertilized egg to mature adult. After hatching from the cocoon, the larvae start feeding. Generally they are fed first with fruit flies and later with crickets. They become reproductively mature after the final moult.
Cupiennius salei