capitalization rules

# Italicize the genus and species designation (Latin name) of a plant or animal; capitalize the genus name but not the species name. After using the full name once, abbreviate the genus name.

Sequoiadendron giganteum
S. giganteum

# When using a subspecies name, place it after the species name and italicize it. Do not italicize other designations following genus and species or subspecies.

Maranta leuconeura kerchoveana
Rosa rugosa var.

# When including the name of the person(s) who proposed a specific or subspecific name, add the person's name after the genus and species designation; do not italicize it. The name is often abbreviated. (Use of parentheses in the second example means that Walker described the species guttifer but referred it to a different genus.)

Felix leo Scop.
Pycnopsyche guttifer (Walker)

# Capitalize but do not italicize taxonomic divisions larger than genus (kingdom, phylum, class, order, and family).

Animalia

# Do not capitalize anglicized versions of scientific names.

primate (from the order Primata)
sequoia (from the genus Sequoia)

# In general, do not capitalize the names of wild and domestic plants and animals. Capitalize only proper nouns and adjectives used with their original reference.

English ivy
Rocky Mountain sheep
dutchman's breeches

# Capitalize special plant and animal names, especially those that are patented or registered as trademarks; do not capitalize the generic part of the name.

Minnesota Regent apple
Big Boy tomato
Peace rose