Ferocactus peninsulae × rectispinus

This is a cross between Ferocactus peninsulae and F. emoryi (once called F. rectispinus.) This cross occurs naturally in the California and the northern Mexico desert, at least in Baja California Sur.

Plants: Plants are 10–20″ (25–50 cm) tall, rounded or flat-topped. It has clusters of long central spines, the longest up to 1¾″ (5 cm) and typically hook-shaped. Spines are reddish brown or white. Radial spines—thin, almost hairlike white spines underneath the central spines, may also be present.

Fruits: Oblong, scaled, ⅞–1¾″ long ⨉ ⅞–1¼″ in diameter (2.5–5 ⨉ 2.5–3.5 cm), with black seeds 1/16″ (2 mm) in diameter.

Habitats: Often on coastal high cliffs in central Baja California, Mexico. It is usually found near the coast in the vicinity of Bahía de la Concepción. The Cerro Colorado population is more inland and farther north than any previously documented.

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	Caryophyllidae	Cacti, many other succulents, carnivorous plants, and leadworts
Order	Caryophyllales	Includes cacti, carnations, amaranths, ice plants, and many carnivorous plants
Family	Cactaceae	Succulent (water-storing) plants, often spiny
Genus	Ferocactus	From the Latin ferus, “fierce,” and cactus, referring to its heavy spines
Species	peninsulae	From the Latin paeninsula, “almost an island,” derived from paene, “almost,” and insula, “island”
×	rectispinus	“Straight-spined,” from Latin recks, “straight,” and spineus, ”spinous”

About plant names...

Ferocactus peninsulae × rectispinus description by Thomas H. Kent, not updated.