Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If you need an accessible version of this item please contact JSTOR User Support

Evolution, Phylogeny, and Systematics of the Juglandaceae

Paul S. Manos and Donald E. Stone
Annals of the Missouri Botanical Garden
Vol. 88, No. 2 (Spring, 2001), pp. 231-269
DOI: 10.2307/2666226
Stable URL: http://www.jstor.org/stable/2666226
Page Count: 39
  • Read Online (Free)
  • Cite this Item
If you need an accessible version of this item please contact JSTOR User Support
Evolution, Phylogeny, and Systematics of the Juglandaceae
Preview not available

Abstract

A comprehensive systematic investigation was conducted on the extant Juglandaceae based on 25 species representing a broad sample of generic and infrageneric diversity. A total of 206 phylogenetically informative characters derived from morphological, chemical, chromosomal, and sequence-based studies formed the basis for comparative studies. Phylogenetic analysis was used to infer relationships and examine patterns of convergence in key biochemical and morphological traits associated with dispersal biology. Separate and combined parsimony analyses of three previously unpublished data sets (ITS, chloroplast DNA, morphology/chemistry) supported two major clades, Juglandoideae and Engelhardioideae, in agreement with a recent subfamilial classification. Within Engelhardioideae, the genus Engelhardia was found to be paraphyletic, as E. roxburghiana of the monotypic section Psilocarpeae was resolved as sister taxon to a New World subclade composed of Oreomunnea + Alfaroa. Within Juglandoideae, two tribes are recognized: Platycaryeae and Juglandeae. The monotypic genus Platycarya formed the sister group to Juglandeae, which was resolved fully (Carya-(Juglans-(Cyclocarya + Pterocarya))). Two new subtribes, Juglandinae and Caryinae, are described based on the cladistic pattern. Unique morphological apomorphies were detected for all genera, including the previously little-studied Cyclocarya, which was also determined to possess a novel base chromosome number for the family (N = 28). The nested position of Annamocarya sinensis within Old World Carya, combined with its lack of unique apomorphies suggested sectional recognition within Carya might be more appropriate for this taxon. Phylogenetic context was used to interpret patterns of morphological and chemical variation associated with the evolution of seed dispersal and the tropical versus temperate habitat. Although the syndrome of wind dispersal appears to be ancestral within the family, four novel origins of wing tissue are represented by Engelhardia/Oreomunnea, Platycarya, Pterocarya, and Cyclocarya. The convergence on animal dispersal has been achieved through three different developmental pathways in the production of a husk in Alfaroa, Carya, and Juglans. In general, wind-dispersed seeds have epigeal germination and those that are animal-dispersed are hypogeous, but Oreomunnea and Cyclocarya are exceptions in their respective clades by having wind-dispersed seeds with hypogeal germination. The seed-energy reserves are also revealing. With the exception of Oreommunea, wind-dispersed seeds have relatively high concentrations of the unsaturated linolenic (C) and linoleic (B) fatty acids (CB pattern), whereas all animal-dispersed fruits (viz., Alfaroa, Carya, and Juglans), and Oreomunnea, have relatively high concentrations of the unsaturated oleic (A) and linoleic (B) fatty acids (BA or AB pattern). Tropical genera, whether wind- or animal-dispersed (viz., Oreomunnea, Alfaroa, Annamocarya), have relatively high concentrations of the saturated palmitic fatty acid. Conversely, wind- and animal-dispersed fruits of temperate genera (viz., Carya, Juglans, Cyclocarya, Pterocarya, and Platycarya) have relatively low percentages of palmitic acid. The explanation here is based on the fact that seed fats must be fluid at the temperature of the living plant, thus selecting for saturated fats in warm tropical climates and unsaturated lipids in cool temperate climates.

Page Thumbnails

  • Thumbnail: Page 
[231]
    [231]
  • Thumbnail: Page 
232
    232
  • Thumbnail: Page 
233
    233
  • Thumbnail: Page 
234
    234
  • Thumbnail: Page 
235
    235
  • Thumbnail: Page 
236
    236
  • Thumbnail: Page 
237
    237
  • Thumbnail: Page 
238
    238
  • Thumbnail: Page 
239
    239
  • Thumbnail: Page 
240
    240
  • Thumbnail: Page 
241
    241
  • Thumbnail: Page 
242
    242
  • Thumbnail: Page 
243
    243
  • Thumbnail: Page 
244
    244
  • Thumbnail: Page 
245
    245
  • Thumbnail: Page 
246
    246
  • Thumbnail: Page 
247
    247
  • Thumbnail: Page 
248
    248
  • Thumbnail: Page 
249
    249
  • Thumbnail: Page 
250
    250
  • Thumbnail: Page 
251
    251
  • Thumbnail: Page 
252
    252
  • Thumbnail: Page 
253
    253
  • Thumbnail: Page 
254
    254
  • Thumbnail: Page 
255
    255
  • Thumbnail: Page 
256
    256
  • Thumbnail: Page 
257
    257
  • Thumbnail: Page 
258
    258
  • Thumbnail: Page 
259
    259
  • Thumbnail: Page 
260
    260
  • Thumbnail: Page 
261
    261
  • Thumbnail: Page 
262
    262
  • Thumbnail: Page 
263
    263
  • Thumbnail: Page 
264
    264
  • Thumbnail: Page 
265
    265
  • Thumbnail: Page 
266
    266
  • Thumbnail: Page 
267
    267
  • Thumbnail: Page 
268
    268
  • Thumbnail: Page 
269
    269