This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
Backbend Asanas gathers four postures of the hatha yoga repertoire, three of them named directly for an animal whose shape the arched or prone body is said to resemble and the fourth named for a weapon instead.
Bhujangasana rests the body from the navel down on the ground, palms planted, head and chest raised like a snake lifting to strike; bhujanga is the serpent. The Gheranda Samhita claims it raises the bodily heat, destroys disease and awakens the serpent goddess, linking the posture directly to kundalini, claims the atlas reports as the text's own. It is absent from the earlier Hatha Yoga Pradipika, and of the four it is the one most nearly identical to what is taught under the same name today.
Dhanurasana, the bow, has the Pradipika describe catching the toes with the hands and drawing one foot back toward the ear, the body bent as an archer draws a bow. The form usually taught under this name now, lying face down and holding the ankles to lift into a backward arch, is a different shape from the drawing action the classical text sets out.
Matsyasana, the fish, is entered in the Gheranda Samhita from the bound lotus, lying back and supporting the head on the elbows; the text claims it destroys disease. It shares its name with Vishnu's fish avatar and with Matsyendranath without either text drawing that connection itself.
Shalabhasana, the locust, lies face down with the legs raised behind like the insect's own. It appears only in the Gheranda Samhita, one of four prone additions, with the crocodile, camel and serpent postures, that mark the later text's wider range of bodily forms than the earlier manual.