Bota,ümt Jsernat of the Linnean Society t984), 88: 257—277. With 26 figures Wood and stem anatomy of Lardizabalaceae, with comments on the vining habit, ecology and systematics SHERWIN CARLQUIST, F.L.S. Claremont Graduate School, Pomona College, and Rancho Santa Ana Botanic Garden, Claremont. Ca4fornia 91711, U.S.A. Received October /983, acceptedfor publication March 1984 CARLQUIST, S., 1984. Wood and stem anatomy of Lardizabalaceae, with comments on the vining habit, ecology and systematics. Qualitative and quantitative data, based mostly upon liquid- preserved specimens, are presented for Akebia, Bsquila, Decaisnea, Hslboeltia, JJardi.abala, Sinofranchetsa and Stauntonta. Because Decazsnea is a shrub whereas the other genera are vines, anatomical differences attributable to the scandent habit can be considered. These include exceptionally wide vessels, a high proportion of vessels to trachcids (Or other imperforate tracheary elements) as seen in transection, simple perforation plates, multiseriate rays which are wide and tall, and pith which is partly or wholly scierenchymatous. With respect to ecology, two features are discussed: spirals in narrower vessels may relate to adaptation to freezing in the species of colder areas, and crystalliferous sclereids seem adapted in morphology and position to deterrence of phytophagous insects or herbivores. The wood may provide mechanisms for maintaining conduction even if wider vessels are deactivated tethporarily by formation of air embolisms. Wood and stem anatomy of Lardizabalaceae compare closely to those of Berberidaeeae and of Clematis (Ranunculaceae), as well as to other families of Berberidales. Decaisnea is more primitive than these in having consistently scalariform perforation plates and in having scalariform pitting on lateral walls of vessels. A tentative listing of anatomical features which may correspond to generic limits is given. — KEY WORDS:—Ecological plant anatomy — Lardizahalaceae — lianas — vegetative anatomy vines — wood anatomy. CONTENTS Introduction 257 Material and methods 259 Anatomical descriptions of wood 259 Anatomical descriptions of bark and pith 270 Anatomy and the vining habit 271 Ecological conclusions 273 Systematic and evolutionary conclusions 274 References 276 INTRODUCTION Only one genus of Lardizabalaceae, Decaisnea, is shrubby; the remainder are vines. Because wood of neither vines nor shrubs has been studied as much as 257 0024—4074/84/040257+21 503.00/0 © 1984 The Linnean Society of London 13 258 S. CARLQUIST that of trees, the lack of a monographic account of wood anatomy in the family to date is understandable. The summary of Metcalfe & Chalk (1950) represents the best summary to date. An excellent study of anatomy of Lardizabalaceae by Réaubourg (1906) has been little cited because of its limited availability. Réaubourg’s study deals with the vegetative and floral anatomy of the family but slights wood anatomy, presumably because of lack of material. Réaubourg’s monograph includes Sargentodoxa cuneata (Oliver) Rehd. & Wilson under the name Holboellia curteata Oliver. Because Sargentodoxa is placed in its own family by various authors, it is omitted from the present study. Various papers give oblique mention to the wood of Lardizabalaceae. The tracheids and fibriform vessels of the family were viewed by Lemesle (1974a, b, 1955, 1956) largely because of his attempt to incorporate tracheary elements of those types in this and other families into a phylogenetic context which could include cycadophytes as well as flowering plants. A paper by Schönfeld (1954) on a fossil genus of uncertain age from Patagonia, Lardiabaloxjlon5 compares the wood of that fossil and of Lardizabala, and offers some comments on wood features of the other genera. The family Lardizabalaceae consists of about 30 species in eight genera (Cronquist, 1981). However, the geographical distribution of these genera and species makes assemblage of a liquid-preserved collection of stem portions difficult. Fortuitous travels provided me with species in all but one of the genera. Material of Decaisnea fargesii Franch. was provided by the Botanic Garden of Lund. The Goteborg Botanic Garden kindly contributed material of Sinofranchetia chinensis Hemsley. During the summer of 1982, travel in Japan under the auspices of the Japan Society for the Promotion of Science permitted collection in natural habitats of Akebia trfoliata (Thunb.) Koidz. (near Hakone, Honshu), A. quinata Decne. (near Nagasaki, Kyushu), and Stauntonia hexaphyl1a Decne. (summit of Ishigaki I., Ryukyu Is.). During October 1982 field work in Chile yielded Boquila trfo1iata Decne. and Lardiaba1a biternata R. & P. (both in Concepcion Province). Wood and stem anatomy of Lardizabalaceae provide potential aids for placing the family in a phylogenetic system, although the systematic location of the family does not seem controversial. Cronquist (1981), Dahlgren (1980), Thorne (1968) and Takhtajan (1980) place Lardizabalaceae in an order, variously termed Berberidales or Ranunculales, in which other families are Ranunculaceae, Berberidaceae, Sargentodoxaceae, and Menispermaceae. This group of families exhibits numerous primitive floral features, so the question arises as to whether wood features are similarly primitive and whether distinctive habits of some genera in these families (herbs, vines) alter the assemblage of primitive features. As dicotyledonous families containing vining species become better known with respect to wood structure, we can develop further concepts of how the vining or lianoid habit is related to wood anatomy and stem anatomy. Because Decaisnea is a shrub whereas the other genera of the family are vines, Lardizabalaceae is a key family for study in this respect. Wood and bark anatomy prove to be varied within Lardizabalaceae, inviting explanations for this diversity. On this account, discussions are offered concerning ecological factors which could account for these features. The anatomical diversity within the family invites comparison with the taxonomic ANATOMY OF LARDIZABALACEAE 259 system, although the fact that fewer than half of the species in the family could be included in the present studies makes such commentary preliminary at best. MATERIAL AND METHODS The wood samples of Decaisnea fargesii and Holboellia la4folia Wall. were available dried; the remainder of the taxa were preserved in 50% ethanol. No herbarium specimen was preserved for Decaisrzea fargesii. The wood of Holboellia 1atfo1ia was removed from the specimen Mukerji & Santapan 160 in the Makino Herbarium of Tokyo Metropolitan University. For the remaining Lardizalabaceae studied here, voucher specimens are located in the herbarium of the Rancho Santa Ana Botanic Garden. Material of the dried specimens was boiled and stored in 50% ethanol preparatory to sectioning. An attempt was made to section material of all collections on a sliding microtome prior to any softening. This proved successful in some instances. Specimens with larger vessels did not section well, nor did those with large quantities of bark scierenchyma. Consequently, an alternative procedure described earlier (Cariquist, 1982) was invoked. This softening technique obviated difficulties. Histological details were not altered, although the basic nature of ethylene diamine, which is employed in that method, resulted in hydrolysis of portions of starch grains. Sections were stained with safranin or with a safranin-fast green combination. The latter staining method permitted easy observation of pit borders, sieve plates, and other details involving primary walls. Quantitative data are based on 25 measurements per feature unless scarcity of structures (e.g. rays are few in some species) necessitated use of a smaller sample. Number of vessels per mm2 was based on arbitrary scanning transections of wood. Rays were not excluded from this scanning, even if any particular field of view proved to contain rays and no vessels; the mean for this feature is correspondingly lowered by the wide rays prevalent in the vining Lardizabalaceae. ANATOMICAL DESCRIPTIONS OF WOOD Because Decaisnea is a shrub, its wood is considered separately from that of the remaining genera. Within the vining genera, the Asiatic genera are presented before the South American genera. Decaisneafargesii5 Lund Botanic Garden, s. n. (Figs 1—7). Growth rings present, latewood distinguished by narrower and fewer vessels, fibre-tracheids slightly narrower radially (Fig. 1). Vessels mostly solitary, most groupings consist of a pair of vessels. Number of vessels per mm2 of transection, = 93. Vessel diameter, = 63 tm (range: 46—69 tm). Vessel wall thickness. .‘ 1.8 JIm. Vessel elements with scalariform perforation plates (Fig. 3), bars slender and minimally bordered. Number of bars per perforation plate, . = 12.8. Vessel to vessel pitting scalariform (Fig. 4). Vessel to fibre-tracheid pitting scalariform to opposite (Fig. 5). Vessel to axial parenchyma pitting scalariform chiefly (Fig. 7). Spirals lacking in all vessels. All imperforate tracheary elements may be termed fibre-tracheids by virtue of presence of borders on the pits. Pits are small 260 S. CARLQUIST d Figures 1—7. Decaisneafargeszi (Lund Botanical Garden, sn.), wood sections. Fig. 1. Transection: vessels comparatively narrow. Fig. 2. Tangential section: multiseriate rays narrow. Figs 3—7. details from radial sections. Fig. 3. Typical scalariform perforation plate. Fig. 4. Scalariform intervascular pitting. Fig. 5. Scalariform-opposite vessel to tracheid