Growth form and current name
Cephalocereus tetetzo is native to the Mexican states of Puebla and Oaxaca. In ecological literature it most often appears as Neobuxbaumia tetetzo. The current POWO treatment associates these names with the same species. Relationships recovered in the 2017 analysis place it close to C. senilis and C. columna-trajani, within a genus that also includes the former Neobuxbaumia. [2-WWW] [Tapia et al. 2017]
The adult plant forms thick, upright stems with branches. The 2017 key identifies it using, among other characters, brownish hairs covering the mature apex, conspicuous areole-associated projections and flowers arising in the apical region. These characters are assessed together. Close relationship to species with a lateral cephalium coexists here with a different organization of the flowering region. [Tapia et al. 2017]
Young plants beneath a nurse shrub
In the Tehuacán Valley, young cacti frequently establish beneath trees and shrubs, including Mimosa luisana. The nurse plant creates a shaded microhabitat with less direct solar radiation. An experiment described in the 1991 paper’s abstract linked greater seedling survival to shaded conditions. Excluding consumers also improved survival. Plant shelter and animal interactions thus affect different aspects of the young cactus’s fate. [Valiente-Banuet and Ezcurra 1991]
Plants at different developmental stages occur together beneath the shrub canopy. A young cactus benefits from shelter, and its stem eventually rises above the shrub. Their prolonged association provides an opportunity to study changes in the balance of interactions. The water-transfer experiment examined adult cacti and shrubs sharing a vegetation patch. Its findings apply to such pairs near the end of the dry season. [Montesinos-Navarro et al. 2019]
Flowers and bats
The flowers are visited by the bats Choeronycteris mexicana and Leptonycteris yerbabuenae. A study published in 2023 compared correspondence between the animals’ head and cranial traits and floral structure, and analysed their pollen loads. In the available abstract, the authors reported a greater probability of pollination by L. yerbabuenae. The inference was based on morphometric traits and pollen, which defines the scope of this assessment of pollinator contributions. [Sánchez-Collazo et al. 2023]
Water moving to a neighbouring plant
A study published in 2019 described an experiment using water labelled with deuterium, a stable hydrogen isotope. The tracer was introduced into the water-storage parenchyma of adult cacti. Three weeks later, enrichment was detected in the xylem water of neighbouring M. luisana shrubs. Comparison with pretreatment samples and shrubs from adjacent patches supported the inference of water movement between plants. [Montesinos-Navarro et al. 2019]
The study demonstrated that such transfer can occur in one field system. The amount of water transferred naturally, its route through the root zone and its consequences for reproduction of both partners require further measurements. The experiment is described in a separate article on water transferred to a nurse shrub. In this species account, the finding adds to the picture of a plant whose water reserves can take part in interactions with its neighbours. [Montesinos-Navarro et al. 2019]
Related articles
Materials from the author's archive
The species also appears in Konrad Szychowski's private material archive. [Flores Martínez et al. 2002] [Hernández-Oria et al. 2003] [Martínez et al. 2001]
Synonyms and names in the literature
Neobuxbaumia tetetzo · Carnegiea tetetzo · Pachycereus tetetzo · Cereus tetetzo · Pilocereus tetetzo [2-WWW]