Tuesday, May 20, 2014

Samoan Hoya Species

The present study was undertaken with the cooperation of Dr. Art Whistler of the University of Hawaii. He kindly sent me his collection of Herbaria sheets which form the major basis for the following detailed study. He also sent me a collection of photo slides taken of the hoya species as they were collected and studied by him in Samoa. My tendency is to look at all the details of a plant and not to gloss over characters I feel may be important in delineating species. I have observed after years of collecting that most species are limited to small areas and to rather narrow elevation and environmental niches. Suffice it to say there are a few species, which are widely adapted and have a broad variability (cline). Even these broadly distributed hoya species seem to be confined to specific elevations. Because of my observations, these habitat patterns are uppermost in my considerations and I am slow to lump materials unless specific data shows otherwise. I have also found that the type descriptions in particular become eroded, expanded and denigrated over time. Many later descriptions are in direct contradiction to earlier Type descriptions and yet this later material is often used in citing synonymies.

I have discussed under “Materials and Methods” some of the difficulties in photographing these very small structures. There is a loss of resolution and detail at every step of the process in bringing this work to publication. I suppose we all wish for more money, better equipment, and above all more time. The expenses and time of all this work is borne by me personally. Many thousands of negatives and pictures have been filed and labeled. These form the data base for this and further studies. I feel a photographic record is invaluable, since at any time I can refer back to the actual photo. I continually re-photograph species so I am able to study any variations occurring over time. In addition, clones bloomed in many locations are added to the photographic and data record on a continuing basis, along with drawings and critical measurements. With the advent of computers it is easy to make necessary corrections and additions to a data base and to then from time to time release updated publications.

Finally it is much more difficult to work with herbarium material than it is with fresh material especially the flowers. There is slight differences in measurements that occur between in vitro and in vivo material. One also cannot see the overall presence that a living plant presents. All we have on a herbarium sheet is a stem laid flat, there is no conveyance of vigor, whether it clumps, dangles, twines, rambles, creeps or many of the other distinct character a live plant conveys. The field observation is a far superior method in determining hoya species than attempting to do the same from herbarium sheets. Actually a combination of these to methods is almost essential to getting it right!

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1 comment:

  1. UPDATE: we have updated these files to a new server. Everything should work well now. Documents I, II, III. :-)