Taylor - Roots and Mucilage in Copiapoa

Nigel P. Taylor
Living Collections Dept, Royal Botanic Gardens Kew, Richmond, Surrey, TW9 SAB, U.K

During a fieldtrip to Chile in 1990, I made observations on the roots and mucilage of various species of Copiapoa . The story is more complex than I recalled at the recent ICSG meeting when, having temporarily mislaid my field notebook from the trip, I was speaking from memory! Having now found the notebook, I can list my key observations. For the purpose of this note they are summarized in the species-groups corresponding to the four main ones we distinguished. The correlation is generally good, and it appears that C. desertorum, C. longistaminea and C. marginata can easily be distinguished from their relatives or look-alikes (i.e. C. rupestris, C. cinerea and C. calderana respectively) on the presence of stem mucilage. The status of C. longistaminea remains uncertain and there are other apparent anomalies needing further study.

Roots tuberous, mucilage present (Marginata group):

C. desertorum (Cifuncho; root napiform, necked, flowers red);

C. marginata (N of Chañaral; observations repeated for population 15 km N of Caldera, Qda El Leon and at Morro Copiapó, the supposed locus classicus;

C. sp. nov. (1) (Botija, 300-500 m; roots tuberous and fusiform, not connected to stem by a neck; [mucilage presence/absence not recorded]

Anomalous?

C. rupestris (syn. C. rubriflora) (7 km 5 of Taltal). Though supposedly a member of the C. marginata group, this did not have mucilage.

Roots non-tuberous, no mucilage (Cinerea group):

C. sp. nov. 2 (Botija; low elevation near mouth of Qda; roots not wiry and woody);

C. serpentisulcata (S of Pan de Azucar Guest House);

C. malletiana (C. carrizalensis) (SW of Totoral);

C. cinerea (Las Breas, 8 km S of Taltal; type loc.)

Anomalous?

C. longistaminea (Qda de las Lozas). Though supposedly a member of the C. cinerea group, this had mucilage. The roots were not tuberous. There may have been hybrids here with sympatric C. cinerea.

Roots tuberous, mucilage present (Humilis group):

C. humilis (Qda El Leon, Qda de las Lozas);

C. varispinata (various localities 50-70 km N of Paposo: on the coast outside Qda Botija, Miguel Diaz / Punta dos Reyes, Qda Izcuna and Punta Colorada)

Roots tuberous, no mucilage (“The Rest“):

C. grandiflora (Qda de las Lozas);

C. cinerascens (S of Pan de Azucar Guest House);

C. cinerascens var. intermedia (Barquito);

C. calderana (N of Caldera);

C. atacamensis (Low elevation near mouth of Qda Botija: root napiform, connected to stem by neck);

C. echinata (SW of Totoral);

C. megarhiza (type loc.);

C. laui (Qda de las Lozas)

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