Stem Anatomy and the Evolution of Woodiness in Piperales

Abstract

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A review of the plants of the Princeton chert (Eocene, British Columbia, Canada)

“…One possibility is the recently described Saururus tuckerae, a plant whose modern counterpart grows today extensively along marginal aquatic zones. Stem anatomy, leaves, and wood anatomical structure of extant Saururus bear some reasonable similarities to Eorhiza Carlquist et al 1995;Carlquist 2009Carlquist , 2013Isnard et al 2012;Trueba et al 2015). A reassessment of these and some other Princeton chert plants, in light of recent knowledge about phylogenies, may help us better understand the plants that grew in this Eocene wetlands of the Okanagan Highlands and the paleoenvironment they represent.…”

Cambial variations of Piper (Piperaceae) in Taiwan

“…The most outstanding anatomical character in the Piperaceae is the nature of the vascular bundles in the stem. In all species of Piperaceae studied to date in the genera Piper , Manekia Trel., and Zippelia Blume, vascular bundles are organized in two or more concentric rings, a characteristic that is not present in other genera in Piperaceae (Trueba et al 2015 ).…”

Structure and ontogeny of successive cambia in Tetrastigma (Vitaceae), the host plants of Rafflesiaceae

“…(Pace, personal observation), and to the arboreal Leea D. Royen of Leeaceae, which is the sister group of Vitaceae (Soejima & Wen, ; Wen et al, , ; Lu et al, ). This type of vascular system, in which the axial elements are segmented in plates, is not exclusive of Vitaceae though, being found also in all the families and genera of the order Piperales (Trueba et al, ), and in all genera of Dilleniaceae, among other taxa. Their presence has been suggested as possibly favoring (an exaptation to) the evolution of the lianescent habit (Trueba et al, ), since wide and high rays make the stems more flexible.…”