Name and distribution
Plants of the World Online accepts Selenicereus setaceus and links it to the historical name Hylocereus setaceus. Its native range includes Bolivia, Brazil, Paraguay and northeastern Argentina. The database describes it as a climbing succulent of the seasonally dry tropical biome. [2-WWW]
Seeds in light and shade
In 2007, Simão, Socolowski and Takaki used seeds from fruit collected from three plants in a seasonal semideciduous forest near São Tomás de Aquino in Minas Gerais. Germination was studied under controlled temperatures and light conditions. The most favourable range, considering percentage, rate and synchronization, was 25–30°C. [Simão et al. 2007, p. 655–658]
Seeds responded to very low light exposure. They also germinated under a spectrum corresponding to canopy shade. The authors associated this response with phytochrome, a light-sensing protein. The tabulated dark treatments showed occasional germination, while the zero-photoperiod experiment confirmed the importance of light access. These procedures are distinguished when interpreting the results. [Simão et al. 2007, p. 657–660]
Implications for sowing
Results for this population support sowing with light access and a moderately warm substrate. The temperature limits tested for germination describe seed responses and have a separate scope from adult-plant tolerance. The experiment did not determine solar exposure requirements for older plants or their overwintering temperature. [Simão et al. 2007, p. 655–660]
Stem growth and mechanics
In coastal restinga forest in Rio de Janeiro State, researchers studied support-searching segments, climbing stems and older basal axes. Their cross-sections ranged from winged to triangular and circular. Young segments obtain mechanical support from the cortex and outer skin, while the central wood cylinder contributes to bearing other forms of loading. Changes in stem organisation accompany changes in its position and function during growth. [Bastola et al. 2021, Bastola et al. 2021, pp. 2–9, Soffiatti and Rowe 2020, Results] [Soffiatti and Rowe 2020, Bastola et al. 2021, pp. 2–9, Soffiatti and Rowe 2020, Results]
Spines and roots on a support
Mature spines act as small hooks directed basally and sideways. Contact with a surface irregularity can stabilise the stem immediately. Adventitious roots develop in connection with the internal wood cylinder, pass through the cortex and later reinforce anchorage. The 2023 study distinguished the strength of connections within the plant from adhesion of a root to a tree surface. This distinction matters when interpreting experimentally measured forces. [Rowe et al. 2023, Rowe et al. 2023, sections 2.3, 3.1–3.3, 4.2]
Related articles
Materials from the author's archive
The species also appears in Konrad Szychowski's private material archive. [Schumann 1890, file p. 18]
Synonyms and names in the literature
Hylocereus setaceus · Cereus setaceus · Mediocactus setaceus [2-WWW]