Sunflowers belong to the helianthus genus, which has 67 species including the Jerusalem artichoke.
From the telegraph.co.uk
Rather than reaching for the sky, this member of the helianthus clan has lax stems that will clothe hanging baskets with dozens of small yellow blooms between July and October.
From the guardian.co.uk
In the warm, shallow waters of the Caribbean Sea, especially in the coral reefs around Cuba, lives a species of sea anemone called Stichodactyla helianthus.
From the newscientist.com
More examples
Sunflower: any plant of the genus Helianthus having large flower heads with dark disk florets and showy yellow rays
The genus Helianthus L. comprises 52 species and several subspecies in the Asteraceae family, all of which are native to North America, with some species (particularly Helianthus annuus (sunflower) and Helianthus tuberosus (Jerusalem artichoke) cultivated in Europe and other parts of the world ...
A taxonomic genus, within tribe Heliantheae - the sunflowers