Wood anatomy of Cupressus and its relation to geographical distribution

Abstract

The wood anatomy of 14 species of Cupressus was studied to determine whether there is a pattern of wood anatomical diversity between the species from the North and Central American (western) region and the Eurasian (eastern) region. Xanthocyparis vietnamensis and Chamaecyparis nootkatensis (syn. Xanthocyparis nootkatensis) were also studied to compare their wood anatomy, given their recent inclusion by some authors in Cupressus. The arrangement of the axial parenchyma, morphology of the transverse end walls of the axial parenchyma, presence of ray tracheids, typology of the end walls of the ray parenchyma cells and ray height support to some extent the division of Cupressus into two large groups: the American group (western region) and the Eurasian group (eastern region), as proposed in molecular phylogenetic studies. The wood anatomy of Chamaecyparis nootkatensis shares the presence of ray tracheids and the same ray typology with American Cupressus, and has the same ray height as Eurasian Cupressus. In contrast, Xanthocyparis vietnamensis shares the absence of ray tracheids and the same ray typology with Eurasian Cupressus, and has the same ray height as American Cupressus.

MioceneCupressinoxylonfrom Gökçeada (Imbros), Turkey withProtophytobiacambium mining and the study of ecological signals of wood anatomy

“…It appears that the co–occurrence of both smooth and nodular end walls of ray parenchyma can be regarded either as a special ontogenetic character related e.g ., to juvenile woods ( IAWA Committee, 2004 ); or as a character related to particular genera, e.g ., Glyptostrobus ( Visscher & Jagels, 2003 ), Fitzroya ( Gasson, Baas & Wheeler, 2011 ), Cryptomeria , Diselma , Fokienia , and Sequoiadendron ( Esteban et al, 2004 ); or even to genera of a particular region, e.g ., North American Cupressus ( Román-Jordán et al, 2016 ). Regarding the last–mentioned genus, the molecular phylogenetic analysis of Cupressus ( sensu lato) by Adams, Bartel & Price (2009) has revealed a new genus for the North American Cupressus species: Hesperocyparis Bartel & R. A.…”

“…Additional support regarding the distinction of the western Cupressus clade from the eastern clade has been provided by xylotomical studies. Román-Jordán et al (2016) have found a link between the wood anatomical characteristics and the biogeographic distribution of Cupressaceae based on observations of specific characteristics, namely the arrangement of the axial parenchyma, transverse end walls of the axial parenchyma, presence or absence of ray tracheids, and typology of the end walls of the ray parenchyma cells and ray height. Based on their study, species with smooth, irregularly thickened, and nodular end walls of axial parenchyma are related to taxa in the North American region.…”

“…Following the anatomical features described in Román-Jordán et al (2016) , we arrived at the conclusion that our wood shares the majority of the characters including distinct growth ring boundaries; gradual transition from early– to latewood, axial parenchyma that is diffuse and marginal with smooth, irregularly thickened and nodular transverse end walls, ray tracheids, horizontal and end walls of ray parenchyma that are mostly smooth, presence of indentures, cupressoid cross–field pits, height of rays up to 15 cells, and uniseriate rays (with the extant H. macrocarpa (Hartw.) Bartel (formerly C. macrocarpa Hartw.…”

“…Several works on Hesperocyparis have been published recently ( e.g ., Adams, Bartel & Price, 2009 ; Terry, Bartel & Adams, 2012 ; Terry et al, 2016 ; Leslie et al, 2018 ; Zhu et al, 2018 ; Yang, Ran & Wang, 2012 ; Román-Jordán et al, 2016 , 2017 ) that provide information about the capacity for dispersal of this genus over great distances during the past, in contrast with the extant species. Migration from Asia across Beringia is borne out, providing different ages for the possible divergence between Callitropsis nootkatensis – Xanthocyparis vietnamensis lineage and the New World cypresses (NWC): late Eocene according to Mao et al (2010) and Yang, Ran & Wang (2012) ; middle Miocene sensu Leslie et al (2012) ; and middle Eocene as supported in Terry et al (2016) .…”

Recent History, Use and Forgetfulness of the Cypress Forest of Fontegreca (Southern Italy)

“…Cupressus s.l. is distributed throughout the Northern hemisphere, in the Mediterranean region, in Eurasia and North and Central America [5]. Mediterranean Cupressus taxa have today a very fragmented distribution [6] as a result of both population dynamics, occurred during their long history, and human pressure [6,7].…”