Cirsium horridulum (Purple thistle)

4/11/2015 · Loop Road, Big Cypress National Preserve, Florida · ≈ 1 × 1′ (32 × 37 cm)

4/14/2015 · Long Pine Key, Everglades National Park, Florida · ≈ 1½ × 1½′ (44 × 45 cm)

4/11/2015 · Loop Road, Big Cypress National Preserve, Florida · ≈ 1 × 1½′ (37 × 49 cm)

Kingdom	Plantae	Plants, but not fungi, lichens, or algae (from Stearn's Botanical Latin)
Subkingdom	Tracheobionta	Vascular plants—plants with a “circulatory system” for delivering water and nutrients
Division	Magnoliophyta	Flowering plants, also known as angiosperms
Class	Magnoliopsida	Dicotyledons—plants with two initial seed leaves
Subclass	Asteridae	A large class that encompasses asters
Order	Asterales	Flowering plants with a central disk flower and surrounding petals, like daisies
Family	Asteraceae	The aster family, which also includes daisies and sunflowers; from the Greek ἀστήρ, “star,” for the star-shaped flowers
Genus	Cirsium	From Greek kirsion, “a kind of thistle”
Species	horridulum	Very prickly or bristly