Unable to connect to database - 17:57:49 Unable to connect to database - 17:57:49 SQL Statement is null or not a SELECT - 17:57:49 SQL Statement is null or not a DELETE - 17:57:49 Botany 2008 - Abstract Search
Unable to connect to database - 17:57:49 Unable to connect to database - 17:57:49 SQL Statement is null or not a SELECT - 17:57:49

Abstract Detail


Systematics/Phytogeography / Taxonomie/ Section

Tate, Anthony [1], Carlsward, Barbara S. [1], Whitten, W. M. [2].

Perianth anatomy of Maxillaria and related genera (Orchidaceae).

As traditionally circumscribed, Maxillaria is a large orchid genus found throughout the American tropics and subtropics.  Recent molecular phylogenetic analyses show that Maxillaria sensu lato is polyphyletic, and core Maxillariinae have been redefined to include 17 monophyletic genera.  The focus of our study was to find anatomical features within the perianth that could be used to diagnose the newly defined clades of Maxillariinae currently based on molecular data.  Transverse sections of petals were made at 90 μm using a sliding microtome, stained with iron-alum haematoxylin and safranin, and mounted on microscope slides.  In transverse section, all petals of Maxillaria sensu stricto contain at least some scattered, homogeneous fiber bundles, making their presence a potential diagnosable feature of the clade.  Fiber bundles are absent in most other genera, except Rhetinantha.  However, fiber bundles of Rhetinantha are heterogeneous and restricted to the ad- and abaxial surfaces.   Other distinct anatomical features found in Maxillariinae are scattered, sclerified idioblasts and mucilage-containing ground tissue.  Sclerified idioblasts are abundant in Heterotaxis, Rhetinantha, and Maxillaria.  Camaridium, Trigonidium, and some species of Maxillaria possess ground tissue with large amounts of mucilage.  In Maxillaria, these mucilage-containing cells are restricted to a few adaxial layers just below the epidermis.  From the anatomical features examined in our study, fiber bundles seem to be the most useful in diagnosing the genera of Maxillariinae.


Log in to add this item to your schedule

Related Links:
Phylogenetics of Maxillariinae (Orchidaceae)


1 - Eastern Illinois University, Department of Biological Sciences, 600 Lincoln Avenue, Charleston, IL, 61920, USA
2 - University of Florida, Florida Museum of Natural History, Gainesville, Florida, 32611-7800, USA

Keywords:
petals
anatomy
Maxillaria
fiber bundles
sclerified idioblasts
mucilage
phylogenetics.

Presentation Type: Poster:Posters for Sections
Session: P
Location: Ball Room & Party Room/SUB
Date: Monday, July 28th, 2008
Time: 12:30 PM
Number: PSP061
Abstract ID:743


Copyright © 2000-2008, Botanical Society of America. All rights