Open AccessVegetative anatomy and systematics of Triphorinae (Orchidaceae)
Author(s) -
CARLSWARD BARBARA S.,
STERN WILLIAM LOUIS
Publication year - 2009
Publication title -
botanical journal of the linnean society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.872
H-Index - 68
eISSN - 1095-8339
pISSN - 0024-4074
DOI - 10.1111/j.1095-8339.2008.00930.x
Subject(s) - biology , orchidaceae , botany , vascular bundle , systematics , vascular tissue , homogeneous , anatomy , taxonomy (biology) , physics , thermodynamics
Triphorinae represents a group of three anatomically simple genera, the structural features of which are unspecialized. The anomocytic stomatal pattern occurs in all genera; it predominates in Triphora . A foliar hypodermis, sclerenchyma, fibre bundles and stegmata are absent. The mesophyll is homogeneous. The exodermal and endodermal cells in the roots are entirely thin‐walled and tilosomes are absent. However, there are anatomical modifications that appear to be unique: root hairs in Monophyllorchis are borne on velamenal buttresses and, in Psilochilus , they arise endogenously. In the root vascular system of Psilochilus , the metaxylem occurs as a circumferential band. The surfaces of stems in Triphora are tuberculate. Mycorrhizae appear to characterize the root cortices of all genera. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society , 2009, 159 , 203–210.