Family Cactaceae Tribe Opuntieae Rank Species | Subfamily Opuntioideae | |
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Similar Opuntia trichophora, Opuntia atrispina, Opuntia pinkavae, Opuntia repens, Opuntia pusilla | ||
Opuntia diploursina is a species in the Cactaceae family, that grows near the Grand Canyon and Lake Mead National Recreation Area. This species is a close relative of Opuntia erinacea but "...differs in minor spines more closely appressed to pad surface, spines smaller in diameter and more flexible, inter-areolar distance less, upright growth habit, larger fruit with longer, more flexible spines, larger seeds, and diploid chromosome number (2n=22)".
Opuntia diploursina (2n=22) is known to hybridize with O. basilaris (2n=22) wherever the species co-occur. This results in fertile progeny that can backcross with either parent eventually creating a hybrid swarm. The polyploid O. erinacea (2n=44) which is widely distributed in the Mojave and Great Basin deserts, is suspected to be a stabilized allopolyploid derived from O. diploursina and O. basilaris. Some O. diploursina x basilaris progeny resemble O. basilaris var. treleasei (2n=33), an endemic species of California.