Which horoscope sign is a crab?

Cancer is the horoscope sign having a crab.

Cancer ♋ is the fourth astrological sign in the zodiac, originating from the constellation of Cancer. It spans from 90° to 120° celestial longitude. Under the tropical zodiac, the Sun transits this area between approximately June 22 and July 22, and under the sidereal zodiac, the Sun transits this area between approximately July 21 and August 22.

It is one of the six negative signs, and its ruling planet is the Moon. Though some depictions of Cancer feature a lobster or crayfish, the sign is most often represented by the crab, based on the "Karkinos".

Water is the element associated with Cancer, and alongside Scorpio and Pisces, it forms the water trigon. The water trigon is one of four elemental trigons in the zodiac, with the other three being fire, earth and air. When a trigon is influential, it is said to affect changes on earth. Cancer is said to be the house of Neptune and the exaltation of Jupiter, both astronomical bodies over those born under Cancer.