Thermogenesis in four species of Schismatoglottis Calyptrata Clade (Schismatoglottideae: Araceae)

Abstract

Spadix temperature was measured in Schismatoglottis ahmadii, S. lowiae, S. sp. nov., and S. wallichii. The anthesis of S. lowiae, S. sp. nov., and S. wallichii started just after dawn but in S. ahmadii, it began two hours later. Spadix temperatures of the four species increased at the beginning of each of the two successive flowering mornings, corresponding respectively to the pistillate and staminate phases of anthesis. The appendices of S. ahmadii, S. lowiae, and S. sp. nov. underwent the highest temperature increases (average 9.5°C above ambient air) compared to the staminate zone (6.5°C above ambient air); almost no thermogenic activity was recorded in the pistillate zone (0.4°C above ambient air). In inflorescences of S. wallichii, in which the spadix lacks an appendix, the pistillate zone also heated up (2.3°C above ambient air), together with the sterile (2.6°C above ambient air) and the staminate zones (5.2°C above ambient air). Thermogenic patterns varied across species owing to differences in timing of anthesis or spadix structures. The absence of an appendix (sterile floral tissue) in S. wallichii, is not only partially compensated by heat production from the (intermediate) sterile zone but also heat production from the pistillate zone, recorded here for the first time in Tribe Schismatoglottideae.

Patterns and drivers of heat production in the plant genus Amorphophallus

“…The interplay between metabolism, scent production and release, temperature elevation, thermo‐regulation and morphology appears to be more complex than previously assumed. In the meantime, temperature measurements have provided a reliable approximation of thermogenesis in several studies (Seymour et al., 2004; Seymour, Gibernau, & Itoh, 2003) and have been widely used in multiple systems (Hoe et al., 2020; Marotz–Clausen et al., 2018; Prieto & Cascante–Marín, 2017; Sayers et al., 2020; Skubatz et al., 2019). Temperature measurements also present some experimental advantages, such as the possibility of simultaneous individual recording of different floral organs or tissues, and the ease of use, particularly when dealing with large inflorescences.…”

Studies on Schismatoglottideae (Araceae) of Peninsular Malaysia III: New species for the Schismatoglottis Calyptrata Clade

“…3 and 10G). During pollination biology studies by the third author (Hoe and Wong 2016;Hoe et al 2018Hoe et al , 2020Wong et al 2016) it became evident that several populations encountered did not correspond to any of these four species, nor did they match any described species from Sumatera or further east. In conclusion we consider these populations to represent undescribed species and here describe three novel Peninsula Malaysian species belonging in the Calyptata clade.…”