公牛多彩海麒麟（学名：Hypselodoris bullocki），俗称紫海兔，高泽海麒麟属的小型海蛞蝓，分布范围广布于东印度洋与热带西太平洋，远达昆士兰南方。体长约2至4公分，具有细致的体色，外套膜缘呈白色环带状，裸腮橘黄色，触角紫红色，腹足与体色相同，呈紫红或乳白色。本种的外观具有变异性，进行相关的初步调查时，常简单的以「公牛组」（bullocki group）来称呼与本种相关的这类品种或变异型。本种与 Hypselodoris apolegma 近似，不过，本种与H. apolegma 的不同之处在于套膜缘的白纹并无渐层的斑点状扩散。

Hypselodoris bullockii is a species of colourful sea slug or dorid nudibranch, a marine gastropod mollusc in the family Chromodorididae.

Hypselodoris bullockii is quite variable in color. Hypselodoris apolegma, which looks similar to this species (and distinguished by a reticulate pattern gradually merging in to the pinkish purple ), and was assumed to be possibly a different color form of H. bullockii. However, recent phylogenetic data confirm the distinction of the two species, and suggest a sister species relationship between them.