A N F Keys
1 Stems (joints) cylindric, terminal young joints with conspicuously raised mounds (tubercles); spines having surface separate as a papery, deciduous sheath .. Cylindropuntia
1' Stems (joints) strongly flattened, terminal young joints tubercles low or inconspicuous; spines lacking papery, deciduous sheath .. Opuntia
1 Terminal stem segments (joints) typically 150−300 × 15−30 mm, tubercles 15−30 mm long; inner perianth segments yellow; fruits solitary, containing seeds ca. 5 mm long .. Cylindropuntia californica var. parkeri [pics]
1' Terminal stem segments (joints) typically 40−150 × 27−35 mm, tubercles 10−15 mm long; inner perianth segments rose-magenta; fruits often in chains of 2−5, never containing seeds .. Cylindropuntia prolifera [pics]
Opuntia Miller
PLATYOPUNTIA, PRICKLY PEAR
1 Flattened stem segments (cladodes) lacking radial spines
2 Low cespitose plant with blue-green and purplish cladodes at ground level, surface glaucous and minutely papillate; flowers brilliant purple-pink; berris dry and brown, to 25 mm long .. Opuntia basilaris var. basilaris [pics]
2' Large shrub to tree with large green cladodes, surface smooth; flowers bright yellow; berries juicy and vibrant magenta, mostly 67−100 mm long .. Opuntia ficus-indica [pics]
1' Flattened stem segments (cladodes) with radial spines on most areoles
3 Radial spines < 33 mm long, translucent yellow turning red-brown to brown on young cladodes; inner perianth segments yellow but blushed rose from the back and aging orangish, outer filaments 11−12 mm long to inner ones 4.5−5 mm long and orange-yellow, style crimson red to deep rose; berry with clusters of tannish glochids and darker deciduous spines to 15 mm long .. Opuntia oricola [pics]
3' Longest radial spine of most areoles commonly > 30 mm long, not initially translucent yellow; inner perianth segments bright yellow or orange-yellow, outer filaments > 12 mm long and mostly yellow or with green at base, style mostly rose or pink; berry with clusters of brownish glochids and with or without diminutive, fine radial spines
4 Plants typically individual and not in clumps or large clones; cladodes mostly roundish to broadly elliptic in outline with only 2−4 radial spines per areole, the longest spine slender, mostly 45−55 mm long, and brown at base; inner perianth segments 40−45 × 27−34 mm and orange-yellow; berries short-obovoid (lacking a narrow neck below seed chamber); seeds 5−5.5 mm diameter including protruding girdle 1 mm .. Opuntia phaeacantha [pics]
4' Plants typically in clumps or large clones; cladodes mostly obovate in outline with up to 11 radial spines per areole, the longest spine thick, < 40 mm long, and yellowish at base; inner perianth segment mostly bright yellow; berries obovoid with a neck below seed chamber; seeds typically < 5 mm long including protruding girdle ± 0.5 mm
5 Plants typically < 120 cm tall; innermost stamen filaments 10−13 mm long; style 27−28 × 9−9.5 mm, pink or with white base .. Opuntia littoralis [pics]
5' Plants < 100−160 cm tall; innermost stamen filaments > 5−12 mm long; style < 9 mm diameter, rose to pink; plants having various combinations of cladode shapes and spination on cladodes and berries of various species interspecific hybrids and backcrosses ......[Opuntia littoralis × O. oricola (in SH also × O. phaeacantha)]
The text of the above keys used with permission from
A Naturalist's Flora of the Santa Monica Mountains and Simi Hills, California
© Copyright
Barry A. Prigge and Arthur C. Gibson
2013