Current circumscription and former Mammillaria
POWO accepts 36 species of Cochemiea. Many previously bore Mammillaria names, including present-day C. armillata, C. dioica, C. grahamii and C. tetrancistra. Former names remain linked to the appropriate profiles. The accepted circumscription includes plants with varied flower and spine structure. Red, elongated flowers distinguish only part of the genus. [2-WWW]
In 2021, Breslin and colleagues proposed an even broader Cochemiea, also including Neolloydia conoidea and Ortegocactus macdougallii. POWO currently retains Neolloydia and Ortegocactus as separate genera. The publication's proposal and the current list of names thus have different boundaries. Agreement on a broad DNA lineage does not dictate a single rank for its smaller subgroups. [Breslin et al. 2021, Breslin et al. 2021, pp. 313–316. Chincoya et al. 2023, pp. 15–16. POWO, 11 October 2026, POWO records conoidea 168615-2 and macdougallii 176672-2] [Chincoya et al. 2023, Breslin et al. 2021, pp. 313–316. Chincoya et al. 2023, pp. 15–16. POWO, 11 October 2026, POWO records conoidea 168615-2 and macdougallii 176672-2] [2-WWW] [2-WWW] [2-WWW]
Red flowers and the history of traits
The narrow classical Cochemiea group comprised plants with cylindrical stems and long red flowers with bilateral symmetry, distinguishing an upper and lower side. C. thomasii was described within this group in 2020. Flower structure was interpreted as associated with hummingbird pollination. The protologue presented this interpretation as a hypothesis based on the combination of flower traits. [García Morales et al. 2020, pp. 1–5]
Trait reconstruction on the plastid tree indicated frequent occurrence of hooked central spines in the broader Cochemiea lineage. C. halei has straight spines. Hooks also appear in some species remaining in Mammillaria. Their structure helps compare plants, while genus identification requires consideration of many traits and their evolutionary history. [Breslin et al. 2021, pp. 312–315; Fig. 2–3]
Young lineages of the Baja California Peninsula
The 2022 analysis indicated extensive diversification of Cochemiea in the Baja California region. Node ages were estimated from plastid sequences using secondary calibrations from earlier studies. Many divergences among regional lineages fell within the last million years. Broad uncertainty intervals limit precise links between young branches and individual geological episodes. [Breslin et al. 2022, p. 1475–1483; ryc. 1–5]
Diversification rates and inferred lineage movements describe a modelled evolutionary history. Climate change, separation of land areas and seed dispersal are considered explanations of regional diversity. The dependence of diversification rate on hooked spines was weaker after other, unmeasured traits were included in the model. [Breslin et al. 2022, p. 1479–1484]
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Synonyms and names in the literature
Bartschella · Chilita · Fimbriatocactus · Phellosperma [2-WWW]