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Peer Review & Correspondence of Wayne P. Armstrong
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   © W.P. Armstrong 10 May 2017
Since I started my Wayne's Word website in the late 1990s, I have received thousands of e-mail messages from experts throughout the world commenting on my articles. According to Google Analytical, Wayne's Word gets thousands of pageviews each day (see Pageviews and Awards). Some e-mail messages from authorities have offered minor corrections to outdated or controversial material. They have also given me advice and ideas on how to improve my explanations of difficult material. I have also received numerous requests for information, identifications, and images on Wayne's Word to be used in textbooks, magazine articles and exhibitions. Recent image requests for exhibitions include the The Science Museum of Paris and Bergius Botanic Garden, Stockholm University. All of these exhibits acknowledge Palomar College. The following examples are a few of the most interesting.

  1. What Caused The Mental Illness Of Vincent van Gogh?
  2. What Causes The Inflated Stems Of Desert Trumpet?
  3. Is The Story Of Alice In Wonderland A Mushroom Trip?
  4. How Does The Deadly Toxin Of A Cone Snail Kill You?
  5. Do Coconut Pearls Really Exist Or Are They A Hoax!
  6. Does Brodiaea jolonensis Occur In Southern Caliifornia?
  7. Coathored Poison Oak Article With William L. Epstein, M.D.
  8. Cook Pine (Araucaria columnaris) Does Occur In CA
  9. Araucarioxylon Incorrect Name For Petrified Arizona Tree
  10. Peer Review On Wayne's Word Botanical Record-Breakers?
  11. Other Wayne's Word Pages That Were Peer-Reviewed
  12. Image Requests From Authors Of Books, Magazine Articles
  13. Requests: Information & Identifications Of Plants & Animals
  14. Dispute Over Amount Of Urushiol That Could Fit On Pinhead
  15. New Record For Italian Mustard Species In San Diego County
  16. Wayne's Word Lectures: Palomar College & Other Organizations
  17. Correspondence With Experts: Ant Discoveries On Owens Pk
  18. Controversy Over A Proposed Name Change In Landoltia
  19. Coauthored Wolffia Article In Journal Botany Letters 2017

1.  Vincent van Gogh's Illness Caused By Acute Intermittent Porphyria (AIP)
It Was Not Caused By Digoxin Poisoning From The Foxglove Plant.

"The Yellow House" painted by Vincent van Gogh
 about two years before his death in the year 1890.
"Starry Night" painted by Vincent van Gogh
 while in an Asylum at Saint-Remy in 1889.

  Vincent van Gogh & The Absinthe Connection  

At the 52nd annual meeting of the American Association for Clinical Chemistry in San Francisco, California, Dr. Paul Wolf of the University of California at San Diego presented some fascinating information about the glycoside digoxin and how it may have affected the creativity of Vicent van Gogh (1853-1890). According to Dr. Wolf, van Gogh's epilepsy was treated with digoxin from the foxglove plant (Digitalis purpurea). His famous work, "The Starry Night" contains yellow circles around the stars, which are similar to visual problems described by patients with digoxin toxicity even today. Van Gogh also drank the liqueur absinthe on a regular basis. Absinthe is a green, bitter liqueur primarily flavored with wormwood (Artemisia absinthium), a European herbaceous perennial related to the native sagebrush species (Artemisia) of the western United States. Absinthe also contains thujone, a terpenoid component of many essential oils, including those found in Artemisia and the coniferous genus Thuja. Research has shown that thujone not only fuels creativity, but also that an overdose of the compound causes yellow-tinged vision (xanthopsia).

According to Dr. W.N. Arnold, Professor of Biochemistry at University of Kansas Medical Center (personal communication) and author of Vincent van Gogh: Chemicals, Crises, and Creativity Birkhäuser, Boston (1992), the illness of Vincent van Gogh was much more complicated. Van Gogh suffered from acute intermittent porphyria (AIP). This debilitating genetic disease is characterized by excessive production of porphyrins due to the deficiency of a particular enzyme within the heme biosynthetic pathway. The word "porphyria" comes from the Greek "porphyrus," which means purple. People with AIP typically have urine that is red or purple. Another famous person whose madness was attributed to AIP was King George III of England. Elevated concentrations of porphyrins can lead to cutaneous photosensitivity and other neurological abnormalities, including psychoses, hallucinations, convulsions and paralyses. This disease can be exacerbated by maltnutrition and fasting with low-carbohydrate, low protein diets. There is substantial evidence that van Gogh developed an affinity for absinthe. He also took excessive doses of camphor oil to relieve insomnia. According to W.N. Arnold, van Gogh was abnormally sensitive to absinthe because of his congenital disease AIP. H.L. Bonkovsky and W.N. Arnold (1992) have shown that the terpenes camphor, thujone and pinene are porphyrogenic. "The combination of overexposure to camphor, absinthe abuse, and fasting or malnutrition would be injurious for anyone, but devastationg for someone with AIP." Dr. Arnold (2004) summarizes van Gogh in the following two sentences: "He was wonderfully creative because of intelligence, talent, and hard work. He was a genius in spite of his illness - not because of it."

Not everyone agrees that absinthe or digoxin toxicity may have contributed to van Gogh's increasing use of the color yellow in the last years of his life. Perhaps van Gogh may simply have loved the color yellow! Generally the effects of chemically-induced xanthopsia includes color vision rich in yellow but lacking blue. Many of Van Gogh's famous paintings contained the primary colors yellow and blue, and would not qualify as examples of xanthopsia. In fact, according to Dr. Wilfred Niels Arnold, the leading authority on van Gogh's illness, there is no evidence that van Gogh ever took the drug digitalis, and artist preference is still the best working hypothesis for the high yellow canvases. "Also, and more important in the present context, it is absurd to include digitalis poisoning in lists of possibilities to explain all his neurologic and psychotic problems that culminated in suicide."


2.  What Causes The Swollen (Inflated) Stem Of Desert Trumpet?
Is It Really Caused By The Larvae Of A Gall Insect?

Swollen stems of "desert trumpet" (Eriogonum inflatum var. inflatum).

There are many different species of wild buckwheats (Eriogonum) in the southwest, but one of the most unusual is "desert trumpet" (Eriogonum inflatum var. inflatum). As the specific epithet implies, the stems are conspicuously inflated or flared just below the point of branching, vaguely reminiscent of several wind musical instruments. If you look very carefully you may see a small hole near the top of the inflated area. This is the entrance to a miniature food storage room and incubator for minute wasps of the genus Onyerus. The female wasp packs the cavity with insect larvae and then lays her eggs upon them. However, some desert trumpets do not have the inflated stems, and these have been named variety deflatum.

Athough most wildflower books and floras list inflated and deflated varieties of desert trumpet, this may be incorrect according to A.M. Stone and C.T. Mason, Jr. (Desert Plants, 1975). Stone and Mason studied wild and greenhouse populations of both varieties, and discovered that stem inflation was caused by larval feeding of gall insects, including a lepidopteran (Pyralidae) and a beetle (Mordellidae). According to Stone and Mason, the swollen tissue is produced in response to a chemical or physical irritation by ravenous insect larvae imbedded in the plant's tissues. They concluded that "the taxonomic recognition of the varieties "inflatum" and "deflatum" is not based on a genetic characteristic, but on a monstrosity, and has no validity."

The Desert Trumpet Riddle Solved At Last

According to the world authority on the genus Eriogonum, Dr. James L. Reveal of the University of Maryland (personal communication, 1998), the swollen stem of E. inflatum var. inflatum is due to high concentrations of carbon dioxide (CO2) in the solid stem and seems to be related to gas regulation. Although some insects utilize the swollen stem as a larder, the inflation is NOT caused by the larval feeding of gall insects. In fact, during very dry years many populations of var. inflatum will have no or poorly inflated stems. In northeastern Utah and adjacent Colorado, another species E. fusiforme occurs in the tens of millions in a good year, and all have inflated stems even when they are young (and there is no evidence that the inflated stems are caused by insects). E. trichopes in the mud hills of the Borrego Badlands can also be added to this list of inflated stem wild buckwheats. Go to the following link and scroll down.

Unabridged note from revised Jepson Manual: Degree of stem inflation in Eriogonum inflatum correlated positively with CO2 accumulation, and not correlated with insect activity (despite ongoing reports to the contrary).

  Inflated Stem Eriogonum trichopes in Borrego Badlands  


The beautiful, red, fly agaric mushroom (Amanita muscaria) is unmistakable with its bright red cap covered with white scales. Some scholars believe that the original story of Alice's Adventures in Wonderland, where Alice speaks to a green caterpillar seated on a red and white-capped mushroom, is actually the interpretation of a mushroom experience by the author, Rev. C.L. Dodgson of Christ Church College in Oxford (better known by his pen name of Lewis Carroll).

Although the fly agaric is poisonous to humans, there are other species of Amanita that are much more dangerous and are potentially lethal if ingested. Some of the dangerously poisonous species of Amanita are death cap (A. phalloides), death angel (A. ocreata), and panther amanita (A. pantherina). Fortunately these latter deadly poisonous species are not bright red and are seldom confused with A. muscaria; however, they may be confused with other edible mushrooms by inexperienced gourmets.

In sublethal doses, the fly agaric mushroom (Amanita muscaria) may produce visions and delirium, and it is perhaps one of the oldest known hallucinogens. Recent studies suggest that this mushroom was the mysterious God-narcotic "Divine Soma" of ancient India. Thousands of years ago, Aryan conquerors who swept across India, worshiped soma, drinking it in religious ceremonies. Many hymns in the Indian Rig-Veda are devoted to soma and describe the mushroom and its effects. There are reports of Siberian tribesmen who ingested the mushroom to get intoxicated. Since the active chemical passes through the body relatively unaltered, others would drink the urine from these men to get high. This way a few mushrooms could inebriate many people relatively safely and efficiently. Lapland shamans eat fly agaric mushrooms for enlightenment and some authors think this may have given rise to the flying reindeer and the red- and white-costumed Santa Claus legends.

Amanita muscaria was also one of the sacred hallucinogenic mushrooms of the Incas, Mayans and Aztecs. Other psychedelic genera included Psilocybe, Paneolus, Conocybe and Stropharia. For the Indians of Mexico, Central and South America, partaking of these mushrooms was a deeply religious experience, enabling them to communicate with their gods. Cortez reported a mushroom (resembling Amanita muscaria) being eaten during the coronation of Montezuma, and in Guatemala stone carvings dating back to 1000 BC depict curious figures with umbrella-like tops resembling the caps and stalks of an Amanita mushroom. Mushrooms are also depicted in ancient Peruvian vessels and in Mexican Codices. One drawing shows an animal-like messenger from god offering the sacred Amanita to a ruler seated on a throne. And a fresco in a Roman Catholic Church in Plaincouralt (Indre), France depicts Adam and Eve on either side of a tree of knowledge that is unequivocally a branched Amanita mushroom.

Some authors have suggested that the original story of Alice's Adventures in Wonderland, where Alice speaks to a green caterpillar who is seated on a red and white mushroom, is the interpretation of a mushroom experience by the author, Rev. C.L. Dodgson of Christ Church College in Oxford (better known by his pen name of Lewis Carroll). Other students of Amanita and the story of Alice in Wonderland contend that this interpretation is an unsubstantiated rumor. In fact, the selection of a thick-stemmed, red-capped mushroom with white bumps resembling Amanita muscaria actually came from the book's illustrator, Sir John Tenniel. Our modern interpretation of the story has certainly been influenced by Tenniel's illustrations. This fascinating revelation was presented to me in an e-mail message by an articulate English teacher many years ago.


4.  How Does The Deadly Toxin Of A Cone Snail Kill You
Does It Cause Death By Cardiac Arrest Or Asphyxiation?

The shells of cone snails (Conus) are highly prized by beachcombers; however, when these snails are alive they are capable of injecting a painful, toxic venom. When the proboscis is extended from the anterior (aperture) end of the snail (red arrow), a barbed, spinelike, radula tooth is thrust into the prey or potential predator like a miniature harpoon. If handling one of these live snails, never allow the aperture end to touch your skin.

Cone snails of the genus Conus, including the South Pacific C. geographus, can inject a potent neurotoxin (called conotoxin) that belongs to a class of poisons called calcium channel blockers. According to Dr. Bruce G. Livett, Department of Biochemistry & Molecular Biology, The University of Melbourne (personal communication, 2007), cone snails such as Conus geographicus contain omega-conotoxins that block calcium channels; however, it is generally accepted that the cause of death is due to the actions of alpha-conotoxins that block acetylcholine on nicotinic receptors at the neuromuscular junction, therby inhibiting depolarization and contraction of the diaphragm muscle and causing breathing to stop. In this case death is caused by asphyxiation rather than cardiac arrest.

Calcium channel blockers inhibit the flow of calcium ions into cardiac (heart) and smooth muscle cells. A sufficient inflow of calcium ions is necessary for contraction of the heart muscle. Muscle contraction involves the reaction of actin and myosin microfilaments which slide over each other. Calcium is essential for the phosphorylation of myosin; an insufficient uptake of calcium ions can result in cardiac arrest. As a medical treatment, calcium channel blockers are used to lower blood pressure, relieve painful angina, and to stabilize abnormal (irregular) heart rhythms. A calcium channel blocker based on the venom peptide omega-conotoxin MVIIA (Ziconotide) from Cornus magus has been developed commecially by Elan Pharmaceuticals, Inc. as an analgesic for the prevention of severe chronic pain that is resistent to morphine and derivatives. This compound is marketed under the name Prialt. Prialt offers 1,000 times the analgesic power of opiates but without the addiction and waning potency. It is a synthetic compound modeled after a paralyzing toxin made by a Philippine cone snail. A catheter implanted in the spine delivers Prialt directly to nerve cells to block the transmission of pain signals to the brain.


5.  I Once Believed That Coconut Pearls Really Existed
Extraordinary Claims Require Extraordinary Proof

The famous "Maharajah coconut pearl" sitting in the shell of a coconut. This alleged botanical jewel was once on display at the Fairchild Tropical Garden in the city of Coral Gables, Florida. It was given to Dr. Fairchild in 1940. Years later I found a detailed account of Dr. Fairchild's voyages in a used book store. To my astonishment I learned that he never saw the pearl in its original coconut. It was simply placed in a coconut for a photo in the book. This and several other discoveries caused me to question its authenticity.

Disclaimer On The Authenticity Of Coconut Pearls
Alleged Coconut Pearl In Singapore Priced At $60,000
  Legendary Coconut Pearl: Most Valuable Botanical Jewel  

My quest for coconut pearls began during several Palomar College field expeditions to tropical regions in the 1980s and 1990s. My original position regarding the plausibility of coconut pearls was based on a number of reputable sources that verified their authenticity. E.J.H. Corner, Professor of Tropical Botany at the University of Cambridge flatly stated that coconut pearls existed in his classic book The Natural History of Palms (1966): "Inside some coconuts, which seem to have no power of germination, there are found the rare coconut pearls, half to one inch long, made of calcium carbonate, not siliceous as the bamboo pearls, but endowed also with magical properties." Other references were more vague about the existence coconut pearls, but generally concluded that they could be authentic. I had no reason to doubt these authorities.

When I first saw the Maharajah coconut pearl on display at Fairchild Tropical Garden in the early 1990s, I was convinced there might be some truth to the existence of these "botanical gems." Unfortunately, I published an on-line note about this "pearl" in 1996 before I discovered that it did not come from a coconut. My old note still appears on some websites, even though there is overwhelming evidence to show that so-called "coconut pearls" do not come from coconuts! Years later I discovered that the origin of the Maharajah coconut pearl (and other so-called coconut pearls) was secondhand. The original botanist or writer, in this case Dr. David Fairchild, never actually saw the "pearl" in its original coconut. It was presented to him on Celebes Island in 1940. This revelation became clear to me after reading his book Garden Islands of the Great East: Collecting Seeds From the Philippines and Netherlands India in the Junk "Chêng Ho," published in 1943 by Charles Scribner's Sons, New York. A photo of the pearl appeared on page 128 with the following caption: "This rare jewel is pictured about as it would be found in the white meat of a coconut near the end where the sprout comes out through the pore." It is obvious that the "pearl" had been placed in a sectioned coconut for the photograph. In other words, the "pearl" was not photographed in situ within its original coconut.

I began to doubt the existence of coconut pearls when I was offered one over the Internet for $60,000 U.S. dollars. If the seller hadn't been so greedy I might have purchased it; however, the photo image was highly suspect because the "pearl" appeared to be inserted into the sectioned husk of a coconut. When I researched my article for Ornament Magazine (2005), I conducted a thorough library search through the University of California and the Gemological Institute of America. I found many references dating back more than 60 years that clearly showed that coconut pearls in various collections were derived from giant clams or another source, and did not come from coconuts. In fact, the aragonite structure of mollusk shells and pearls can readily be identified using translumination studies with high intensity fiber optic light, X-ray diffraction, and comparisons of their refractive index and specific gravity. It is surprising that some of the authors that have perpetuated the coconut pearl myth did not come across these excellent references.

An alleged coconut pearl in Singapore within the endocarp of a coconut.
Suggested price was $60,000 in December of 2003. Photo by N.M. Ngoi.

In 2007, I submitted a summary of my Ornament article to the Drifting Seed Newsletter in Florida. Apparently Dr. J.V. Veldkamp of the National Herbarium of the Netherlands and editor of the prestigious journal Flora Malesiana Bulletin, saw this newsletter. Completely independent of my articles, he has also been studying coconut pearls called "mestica calappa" and published a paper on this subject for Flora Malesiana Bulletin in 2002. Although he expressed considerable skepticism, he concluded that they might exist based on previous articles prior to 2002, including a few of my own. Like myself, he is now convinced that they are a hoax and is updating his original article in the 2008 issue of Flora Malesiana Bulletin. He is citing my Ornament article, Palomar College and my pages on Wayne's Word. Scholarly journals typically cite botanists through their affiliated institution and herbarium which is published in Index Herbariorum. The official acronym for Palomar College is PASM. So my coconut pearl quest has come full circle, from my early articles in Terra (1992) and Palomar's early website in 1996, to my latest articles in Ornament and The Drifting Seed, culminating in Dr. Velkamp's update for the Flora Malesiana Bulletin. His update is quoted in the following table:

MESTICA CALAPPA, THE COCONUT PEARL. 2. THE MYSTERY UNRAVELLED
(continued from Flora Malesiana Bulletin Vol. 13, p. 153, 2002)

J.F. Veldkamp
Nationaal Herbarium Nederland, Leiden branch
PO Box 9514, 2300 RA Leiden
The Netherlands

In the Flora Malesiana Bulletin of 2002 I wrote a note on the supposed occurrence of "pearls" in coconuts ("Mestica calappa"). Since then, the unnamed collector sent me his specimen for an assay and I asked Mr. J.C. Zwaan, Director of the Gemmological Laboratory, Natural History Museum "Naturalis" here in Leiden, to take a look at it, which he kindly did.

His report was brief and to the point: "I am convinced that this must be a shell based on its chemical composition and structure. I have shown it to a mollusk specialist here, Mr. J. Goud, who could only confirm this". The shell could be of Hippopus sp., or Tridacna sp., or another large shell, but its actual identity remained uncertain. He showed me the specimen and his comparative samples, and I could only agree. And this was such a nice story...

A more extensive report is provided by Brown et. al. (1988) published in a journal that will be unavailable to most botanists. I briefly summarise it here:

The investigation was made on a "?pearl" that had been purchased in Hong Kong said to have an Indonesian origin.

Macroscopic examination showed that it was porcellanous, egg-shaped with 8--10 mm long vertical incisions around the equator (our pearl was completely smooth. JFV). It weighed 24.75 carat and was 14.75 by 15 mm. The specific gravity by hydrostatic weighing was 2.87. Examination with a hand lens revealed that it had a dull porcellanous lustre, was essentially opaque, the incisions had been made with either a file or a rotary abrasive disc, and there was no "flame" pattern on its external surface. X-ray radiography showed that it was formed from a structureless radiopaque material. Translumination by a high intensity fibre optic source revealed a pattern of fine wavy parallel banding that apparently crossed, the growth layers of a thick sea-shell. The origin was confirmed by the aragonite values determined for the refractive index and the specific gravity.

This conforms to the observations made by previous analyses cited in my 2002 paper.

Completely independent of my paper, Wayne P. Armstrong (PASM) published a series on the Internet and in print, the latest one in 2007. At first, he thought that there might be some trace of truth in the story, but concluded "extraordinary claims require extraordinary proof, and the proof is lacking here". He was kind enough to send me some reprints, e.g. the Brown et al. paper mentioned above. See his site https://www2.palomar.edu/users/warmstrong/ww0901.htm#coconut where there is also a picture of Fairchild's Maharaja pearl.

If you search the Internet for coconut pearls, you will run into sites where they are offered for between US$ 60 and 60,000 (!). They might be worth it, as "according to experts in energy flows, the pearl expels negative energy (whatever that is), it brings luck, increases business dealings, and guarantees social success through stimulating personal magnetism of the person (wow!), offers charisma, healing, and lowers fever (so does aspirin)".

By the way, before you rush out to obtain all these benefits, note that Hippopus and Tridacna spp. are cited in CITES Appendix II, which requires a permit before parts of them can be transported (and worn).

References:

Armstrong, W. P. 2007. "Do pearls come from coconuts?" The Drifting Seed 13: 13--17. http://www.seabean.com/newsletters/vol13-1.pdf

Armstrong, W.P. 2005. "Coconut Pearls: A Reevaluation of Authenticity." Ornament 28 (2): 46-49.

Brown, G., S.M.B. Kelly, and J. Snow. 1988. "A Coconut Pearl?" The Australian Gemologist 16 (10): 361-362.

Veldkamp, J.F. 2002. "Mestica calappa, the coconut pearl, trick or true?" Flora Malesiana Bulletin 13: 143--153.

Veldkamp, J.F. 2008. "Mestica calappa, The Coconut Pearl. 2. The Mystery Unravelled." Flora Malesiana Bulletin 14.

Another series of interesting correspondences about coconut pearls came from Wendy Orr, author of the novel "Nim's Island." She was apparently interested in my coconut pearl article on Wayne's Word and wanted to feature the girl in her story finding one in a coconut. The story was later made into a movie starring Jody Foster.


6.  Brodiaea jolonensis Does Not Occur In Southern California
Is Our Coastal Southern Calif. Brodiaea A Different Taxon?

Flowers of Brodiaea jolonensis from Monterey County showing the distinctive purple ovaries. According to Niehaus (1971), this is the only species of Brodiaea in California with purple ovaries. In fact, no populations of Coastal BTK in San Diego County or southern California have ovaries with this dark purple color. Their ovaries are typically green or only slightly tinged with purple. There are also other morphological differences unique to B. jolonensis (see link below).
Brodiaea jolonensis in Monterey County

The possibly unnamed taxon "Coastal BTK" In Southern California

  Does Brodiaea jolonensis occur in Southern California?  

For more than 60 years Brodiaea jolonensis has been listed in floras and plant lists for coastal southern California, and I had no reason to doubt these references. Then my good friend Tom Chester presented his hypothesis that this species doesn't occur here. We checked out populations from Santa Barbara County to the Mexican border, and never found any that fit the true B. jolonensis native to Monterey County of central California. Although our species is similar to B. jolonensis, it also has some features similar to inland populations of B. terrestris ssp. kernensis (BTK). In fact, we referred to our coastal southern California species with the unofficial name of "Coastal BTK." On-line pages of data and images by myself and Tom Chester have prompted a lot of e-mail from brodiaea experts. In fact, the Brodiaea, that we have referred to as "Coastal BTK," is now listed as a possible undescribed taxon under B. jolonensis in the revised Jepson Manual: Vascular Plants of California (2nd Edition, 2011). Ongoing cladistical studies using chloroplast DNA may confirm that this is indeed an undescribed taxon. This brodiaea controversy is an excellent example of how images and data can be disseminated over the Internet before it actually appears in a peer-reviewed printed publication.


7.  Coauthored Article On Poison Oak With Dr. William L. Epstein, M.D.

Poison Oak: More Than Just Scratching The Surface

Modified from article in Herbalgram (American Botanical Council)
Volume 34: 36-42, 1995 by W.P. Armstrong and W.L. Epstein, M.D.


8.  Article About Araucaria For Pacific Horticulture (See PDF File)

The Cook Pine (Araucaria columnaris) Occurs In Southern Californa

Published article in Pacific Horticulure 71 (1): 4-11 and Corresponded with
Dr. Matt Ritter, Professor of Botany and Director of Plant Conservatory,
California Polytechnic State University, San Luis Obispo, California


9.  Article About Araucaria For Pacific Horticulture (See PDF File)

Araucarioxylon arizonicum Not The Correct Binomial
For Arizona's State Fossil at Petrified Forest National Park

Published article in Pacific Horticulure 71 (1): 4-11 and Corresponded with
Paleobotanist Dr. Rodney A. Savidge of the University of New Brunswick


10.  Peer Reviewed Topics On Botanical Record-Breakers

Largest Flying Seed & Exposive Seed Projectile, Hottest Chile Pepper & Jumping Beans


Whirling Nut (Gyrocarpus)

Jumping Bean vs. Jumping Gall

Left: The whirling nut spins like a helicopter propeller. Right: The round jumping gall (top) actually jumps up and down as it moves across your screen. The angular jumping bean (lower) rarely jumps, instead it just rolls, jerks and tumbles across your screen. Both are powered by the force of a small insect larva that literally hurls its body within the gall or bean.
Records are made to be broken, and this is certainly the case with chile peppers. As of February 10, 2012, the world's record for the hottest pepper is the 'Moruga Scorpion' ('Moruga Scorpion' Pepper is the World's Hottest Chile Pepper at more than 2 million Scoville Heat Units, Gregory Reeves, Danise Coon & Paul Bosland, Department of Plant & Environmental Sciences at New Mexico State University, Las Cruces, New Mexico 88003). The mean SHU was 1,207,764, with the highest value at 2,009,231!
Of all the plant species capable of launching their seeds, the most amazing is the sandbox tree (Hura crepitans), a member of the euphorbia family (Euphorbiaceae). This tree is native to the Caribbean region, and the large, pumpkin-shaped seed capsule explodes like a hand grenade when mature, only the shrapnel consists of seeds and bracts. This was one of my favorite lecture topics on Palomar Life Science Dept. field trips to the Caribbean during the 1980s & 90s. The round, flattened seeds are about 3/4 on an inch in diameter (16-19 mm) and are launched at about 150 mph (70 meters per second). The initial explosion sounds like a small caliber hand gun. I recall one exploding in my kitchen cupboard that sounded like a powerful firecracker. The noise actually frightened a guest who was in my kitchen at the time.
The climbing gourd (Alsomitra macrocarpa), native to the Sunda Islands of the Malay Archipelago, produces one of the largest winged seeds up to 5 inches (13 cm) wide inside a large, club-shaped gourd. The football-sized gourds hang from a vine high in the forest canopy, each packed with hundreds of winged seeds. The seeds have two papery wing membranes and become airborne like a glider when released from the fruit. This large, streamlined seed reportedly inspired the wing design of some early aircraft, gliders and kites. Although the seeds vary in shape, some of the most symmetrical ones superficially resemble the shape of the "flying wing" aircraft or a modern Stealth Bomber.

Seed courtesy of The Cucurbit Network P.O. Box 560483, Miami, Florida 33256 USA.

One of the most popular pages on Wayne's Word is Botanical Record-Breakers: Amazing Trivia About Plants. Over the years I have received input from numerous students and professors. A few notable examples include: (1) An engineering class studying the forces exerted by the jumping bean moth larva & whether the bean actually "jumps." (2) A comparison of the motion of jumping beans vs. jumping galls. (3) The world's largest flying seed & largest ballistic seed launched explosively. (4) The world's hottest chile peppers. The chile pepper correspondence came from Dr. Paul Bosland, molecular biologist and director of the Chile Pepper Institute at New Mexico State University. Paul was a student in my general biology and general botany classes at Palomar College during the early 1980s! He is coauthor of the book The Complete Chile Pepper Book (2010). Regarding the amazing gourd family, I received a giant flying seed from gourd expert Dr. D.S. Decker-Walters of the Cucurbit Network. I also received images of penis sheath gourds from a contact in Papua New Guinea (see gourd article in following list of links).

  1. Botanical Record-Breakers
  2. World's Hottest Chile Pepper    
  3. The Largest Ballistic Seed
  4. The Largest Flying Seed
  5. Mexican Jumping Beans
  6. California Jumping Galls
  7. The Wild World Of Gourds


11.  Other Peer Reviewed Pages On Wayne's Word

There are numerous other pages on Wayne's Word where I have received input from colleagues throughout the United States and other countries. The following three pages contain some of the most unique information on Wayne's Word. Special thanks to Dr. Elias Landolt of the Geobotanical Institute in Zurich for his input on my pages about the duckweed subfamily Lemnoideae. Naturalist Steven Disparti provided invaluable insight and references on my pages about the fig & fig wasp, and my page on evolution and the origin of life. I even received e-mail from Richard Dawkins regarding the explanation of vicarious selection in the fig section (Chapter 9) of his book Climbing Mt. Improbable (1996). The coevolution of the fig and its symbiotic wasp is included on my evolution page, probably the most comprehensive page with the largest bibliography of all my Wayne's Word articles.

  1. Evolution & Origin Of Life: Controversies That Have Divided America
  2. Coevolution & Sexual Reproduction Of The Fig & Its Symbiotic Wasp
  3. Taxonomy Of Duckweeds In North America (Subfamily Lemnoideae)  


12.  Image Requests From Authors Of Books & Journal Articles

During the past 15 years I have received numerous requests from authors of books and magazine articles for images on Wayne's Word. Many of these image requests were for textbooks and scholarly (peer-reviewd) journal articles. A few recent requests are:

  1. Vegetable Ivory--For Ivory Identification Poster In Thailand (To Combat Illegal Ivory Trade), World Wildlife Fund and the Conservation Foundation (2011).

  2. Peanut Plant in Full Bloom--For "Creamy & Crunchy: An Informal History Of Peanut Butter, The All-American Food" by Jon Krampner (2012).

  3. Size Of A Grain Of Salt--For Defence Lawyer Presentation In Case Involving LSD (2013).

  4. World's Smallest Flowering Plant--For Feature Article in the German Magazine: "Zeit Wissen" (2013).

  5. World's Smallest Ant--For Ant Exhibition At The Science Museum of Paris (Palais de la Decouverte, 2013-2014).

  6. Airborne Seed Images For "The Seeds of Aril" by R.M. Robinson, Firefall Editions, Canyon, CA 2012.

  7. Harvester Ant Exhibit At The Anza-Borrego Desert State Park Visitor Center, Borrego Springs, CA.

  8. Collected Rare Bee Fly (Bombylius montanus) for Dr. Neal Evenhuis of the Bishop Museum, Oahu, Hawaii.

  9. Plant Fiber Exhibit At Bergius Botanic Garden, Stockholm University, Sweden (March-April 2014).

  10. Two of my images of the western tree cricket (Oecanthus californicus) in chirping mode were used on the website Singing Insects of North America by Dr. Thomas J. Walker, Professor Emeritus, University of Florida.

  11. Three of my images will be featured in the San Diego Natural History Museum's new exhibit: Coast To Cactus In Southern California. San Diego Natural History Museum. San Diego Natural History Museum


Ant Exhibit At The Anza-Borrego Desert State Park Visitor Center

Harvester ant exhibit in Anza Borrego Desert State Park Visitor Center. The following image was used in above ant exhibit (outlined in red).

Harvester ants (Messor pergandei) carrying the plumose achenes of smooth cat's ear (Hypochaeris glabra). Nests of the red California harvester ant (Pogonomyrmex californicus) are nearby and the two species appear to tolerate each other. These ants provide the vital diet for the coast horned lizard (Phrynosoma coronatum). Unfortunately, our native ants have been eliminated throughout coastal San Diego County by the aggressive Argentine ant (Iridomyrmex humilis).


Bee fly Bombylius montanus in Rattlesnake Canyon, Poway, CA. The larva is parasitic on solitary bees of the genus Anthophora (Apidae). According to Dr. Neal Evenhuis at the Bishop Museum, Hawaii, this is a relatively rare species also known from Walker Pass in the southern Sierra Nevada. This furry fly has a long, rigid proboscis that it uses for sipping nectar from flowers.

Rare Bee Fly Collected In San Diego County For Bishop Museum, Hawaii


My image of leaf fibers will be used in a plant fiber exhibit at the Bergius Botanic Garden, Stockholm University, Sweden on May 7 - April 14, 2014.

Thread-like fibers exposed from the leaves of two species of monocots in the agave family (Agavaceae): A. Bowstring Hemp (Sansevieria trifasciata); and B. Giant Yucca (Yucca elephantipes).


A male California tree cricket (Oecanthus californicus) "serenading" me outside my window. Click on the following link to hear its call (wait a moment for sound file to load): Click To Hear Song Of The Above Cricket. More Information about crickets on Wayne's Word: Wayne's Cricket Page.


Three of my images will be featured in the San Diego Natural History Museum's new exhibit: Coast To Cactus In Southern California. San Diego Natural History Museum


13.  Requests For Information & Identifications

I have also received many hundreds of requests for information and identifications of plants and animals featured on Wayne's Word. One of the most interesting came from Wendy Orr in Australia, author of the novel "Nim's Island." She was apparently interested in my article about coconut pearls and wanted to have the girl in her story finding one on a beach. Her story was later made into a movie starring Jodie Foster.

One of the strangest requests came from a woman in Wisconsin who wondered who was defacing her statue of the Virgin Mary. See the following image and a link to my answer to her question!

Click here to see my answer: https://www2.palomar.edu/users/warmstrong/Statue1.htm.

Without a doubt, the most e-mail I have received about a single subject concerns circassian seeds from India, magical red beads--each containing 12 tiny carved elephants.

Magical Seeds From India: https://www2.palomar.edu/users/warmstrong/plmar97.htm.

I receive numerous e-mail messages about where to see wildflowers blooming in southern California.



Where To See Wildflowers In Southern California

Favorite Anza-Borrego SD-Riverside Witch Creek Fire California Special Santa Rosa Plateau Brodiaea Joshua Tree Marine Parasite



14.  Colleague Disputed Gee Whiz Statement About Poison Oak

Some people are so sensitive that it only takes a molecular trace of urushiol (two micrograms or less than one millionth of an ounce) on the skin to initiate an allergic reaction (Epstein et al, 1974). Even the amount on a pinhead is sufficient to cause rashes in 500 sensitive people. The following paragraph and illustration was included to satisfy a skeptical colleague who questioned the amount of urushiol that could fit on the head of an ordinary straight pin.

If 2 micrograms of urushiol is sufficient to initiate a reaction in one hypersensitive person, then 1000 micrograms of urushiol (2 X 500) could initiate reactions in 500 hypersensitive people. But, how much urushiol are we talking about here? I will attemp to relate this amount to cubical grains of ordinary table salt (NaCl). An average grain of salt 0.3 mm on a side weighs about 60 micrograms. Using a grain of this size for an approximate size relationship, 1000 micrograms of urushiol would be roughly equivalent to 1000/60 or 17 grains of salt. A cuboidal grain of table salt (NaCl) 0.3 mm on a side has an area of 0.09 mm². An average pin head with a diameter of 1.5 mm (0.75 mm radius) has an area of 1.767 mm². Dividing the area of a pinhead (1.767 mm²) by the area of a single grain of salt (0.09 mm²) gives a value of 19.63 grains of salt. Therefore,17 grains of table salt would fit on the head of an ordinary straight pin. [Of course, even more grains would fit on the head of a pin if they were moistened and clumped together into several layers.]

Arrangement of 17 uniform grains of table salt (NaCl) on the head of an ordinary straight pin with a diameter of 1.5 mm and area of 1.767 mm². Each grain is 0.3 mm on a side, so that 4.5 grains fit across the diameter of the pinhead (three grains are exactly one mm). Because of their square shape, some of the grains overlap the edge of the round pinhead. Grains of table salt out of a shaker vary slightly in size; we are using salt grains exactly 0.3 mm on a side in this illustration. Fewer salt grains would fit on the head of a pin if larger grains were used.


15.  Correspondence Regarding Discovery Of New Mustard In San Diego County

  Discovery Of Brassica fruticulosa In San Diego Couty  


16.  Given Lectures To State Parks, Organizations, Life Sciences Dept., Etc.

I have given many guest lectures to life science colleges at Palomar College and various natural history clubs and organizations, including Anza-Borrego State Park, California Native Plant Society, San Diego Botanic Garden, and the Southern California Horticultural Society. Rather than create Power Point programs for special topics, I simply use my extensive Wayne's Word website with an LCD projector. If available, I can use a Wi-Fi connection or just project my website offline. The following are some of my lecture topics:

Wayne's Word Lectures

 waynesword.palomar.edu 
waynes-word.com
waynesword.net


17.  Correspondence With Experts Over Ant Discoveries On Owens Peak

   Ants Found On Owens Peak ("P" Mountain)     Ant Index     Ant Photography   

Athough I was fascinated with ants as a child in the 1950s, my primary focus during most of my teaching career was botany. During my retirement years I have once again turned my attention to these marvelous creatures. Ants are very difficult to identify, particularly at the species level. For the identification of several species found on nearby Owens Peak, I have corresponded with ant authorites Alex Wild at the University of Illinois and Phil Ward at University of California, Davis. On my Wayne's Word Ant Index, all species found on Owens Peak north of Palomar College are designated with OP. The following image shows three unusual species found at the summit of Owens Peak in 2013:


18.  Contoversy Over Name Change In Genus Landoltia

Part 1. Brief History Of The Taxonomy Of Landoltia

If This Discussion Is Too Long & Complicated, Please Skip To Part 2

Many traditional phylogenetic groupings of species within families and genera are not monophyletic and are inconsistent with modern cladistical analyses based on DNA. In other words, the groupings are paraphyletic or polyphyletic, and do not show all species within a group descending from a common ancestor. Monophyly is the natural evolutionary pattern in which all species are descended from a common ancestor. In order to have consistent computer-generated, monophyletic cladograms, it is sometimes necessary to change paraphyletic and polyphyletic groupings by moving species into different genera, and by moving genera into different families. Many of the taxonomic revisions in the Jepson Manual 2nd Edition (2012) were made in order to have consistent monophyletic groupings. This is why Spirodela punctata was placed in the genus Landoltia and why the Lemnaceae was placed in the familiy Araceae.

The cladogram (left) is from D.H. Les and D.J. Crawford (1999). It has high boot strap values and is based on molecular (rbcL) data from chloroplast DNA. It clearly shows that a grouping composed of 3 species of Spirodela is paraphyletic. This is why S. punctata was placed in the monotypic genus Landoltia.

  Monophyletic Groupings: All Descendants From A Common Ancestor  

In 1999, D.H. Les and D.J. Crawford proposed the new genus Landoltia containing one species L. punctata, formerly Spirodela punctata. This species is morphologically intermediate between Lemna and Spirodela. According to Les & Crawford, it represents an isolated clade distinct from both Lemna and Spirodela. Without this change, the genus Spirodela would be paraphyletc.

  • Les, D.H., and D.J. Crawford. "Landoltia (Lemnaceae), A New Genus of Duckweeds." Novon 9: 530-533.

Morphological
Characteristic
Spirodela intermedia
Spirodela polyrrhiza
Landoltia punctata
Formerly Spirodela punctata
Lemna
All Species
Prophyllum At Base Of Frond
Present
Present But Reduced
Absent
Number of Roots
Penetrating Prophyllum
S. intermedia: 2 to 5
S. polyrrhiza: 1 (rarely 2)
All Roots
No Prophyllum
Overwintering Turions
S. intermedia: None
S. polyrrhiza: Present
None Distinct; Some Small
Fronds Resemble Turions
Present in
L. turionifera
No. of Veins In Frond
7 to 16
3 to 7
1 to 5
No. of Roots
7 to 21
Typically 2 to 5
Only 1
Root Tracheids
Extend to Tip
Basal Only
Absent
Dorsal Meristem of New Fronds
On One Side
(Lateral on other side.)
On Both Sides
On Both Sides
External Anther Locules
Do Not Extend Above
Internal Locules
Extend Slightly Above
Internal Locules
Extend Above The
Internal Locules
Brown Pigment Cells In Fronds
Present
Present
Absent
Cells With Crystals
Raphides & Druses
Raphides & Druses
Raphides Only

A comparison of morphological features between Landoltia, Spirodela and Lemna. With so few taxonomic characteristics, these assume a more important role in distinguishing genera. Spirodela punctata has a taxonomic position intermediate between Spirodela (S. intermedia & S. polyrrhiza) and Lemna. A hypothetical cladogram in Les and Crawford (1999) based on morphological data from Landolt (1986) revealed a paraphyletic grouping of Spirodela before Spirodela punctata was finally placed in the monotypic genus Landoltia.

According to Professor Dr. Elias Landolt (personal communication, 2001), the creation of the new genus Landoltia is not necessary based on a purely morphological point of view; however, based on DNA and enzymatic studies, the change is warranted in order to form phylogenetically consistent taxa. The inclusion of a fifth genus Landoltia appears to be necessary based upon a comprehensive analysis of the Lemnaceae by D.H. Les, D.J. Crawford, E. Landolt, J.D. Gabel, and R.T. Kimball (2002). More that 4,700 characters were studied, including data from morphology and anatomy, flavonoids, allozymes, and DNA sequences from chloroplast genes (rbcL, matK) and introns (trnK, rpl16).

The Angiosperm Phylogeny Group (APG) has proposed some significant changes in the classification of many traditional angiosperm families, including the placement of all duckweeds in the Araceae rather than the Lemnaceae. Nomenclatural changes are cited under the APG II system (2003) and superceeded by APG III system (2009). These changes are based on computer-generated evolutionary trees or cladograms. Thousands of data characters have been used, including morphology, anatomy, flavonoids, allozymes, and DNA sequences from chloroplast genes and introns. The Jepson Manual Second Edition (2012) essentially follows the changes summarized in the following reference by W.T. Judd, et al. 2008. Since the genus Landoltia was proposed by D.H. Les and D.J. Cawford in 1999, several classic papers on the phylogeny of the duckweed subfamily (Lemnoideae) and other aroids (Araceae) have used the name Landoltia. In my opinion, the name Landoltia is warranted because it is consistent with the objectives of the Jepson Manual 2nd Edition (2012) based on phylogenetic studies using plastid DNA.

  • Judd, W.S., Campbell, C.S., Kellogg, E.A., Stevens, P.F., and M.J. Donaghue. 2008. Plant Systematics: A Phylogenetic Approach (Third Edition). Sinauer Associates, Inc., Sunderland, Massachusetts. 611 p.

  • Les, D.H., D.J. Crawford, E. Landolt, J.D. Gabel, and R.T. Kimball. 2002. "Phylogeny and Systematics of Lemnaceae, the Duckweed Family." Systematic Botany 27 (2): 221-240.

  • Cabrera, L.I., Salazar, G.A., Chase, M.W., Mayo, S.J., Bogner, J., and P. Davilá. 2008. "Phylogenetic Relationships of Aroids and Duckweeds (Araceae) Inferred From Coding and Noncoding Plastid DNA." American Journal of Botany 95 (9): 1153-1165.
See Images Of Landoltia punctata (syn. Spirodela punctata)
  Cladogram For The Arum Family Based On Chloroplast DNA  


Published Names For This Species

Lemna punctata G.F.W. Meyer

This was Meyer's original name based on the type specimen collected along the Essequibo River, Guyana, South America in 1818. Unfortunately, Meyer's original type specimen was lost.

Spirodela punctata (G.F.W. Meyer) Thompson

C.H. Thompson placed this species in the genus Spirodela in 1898. Since the type specimen was lost, he based the new name on a specimen from the 1938-1842 Wilkes Expedition, labeled Orange Harbor, Tierra del Fuego. According to Landolt (1986), Thompson neotypified this species in his 1898 publication.

Landoltia punctata (G.F.W. Meyer) Les & D.J. Crawford

In 1999, D.H. Les and D.J. Crawford placed this species in the genus Landoltia based on DNA evidence.


Re-Neotypification Of G.F.W. Meyer's 1818 Type Specimen Of "Lemna punctata"

Note: This is a complicated taxonomic subject involving many articles from the International Code of Nomenclature For Algae, Fungi, and Plants (Melbourne Code) 2011: Available on-line at: http://www.iapt-taxon.org/nomen/main.php.

An argument for replacing the names Landoltia punctata and Spirodela punctata with the previous name Spirodela oligorrhiza has been made by Daniel B. Ward (2011). In order to make sure we are referring to the same species, Ward has suggested calling this "Lesser Greater Duckweed" to avoid confusing it with the larger species of Spirodela (S. polyrrhiza & S. intermedia) called "Greater Duckweeds." In this article I will simply call it LG Duckweed instead of Lesser Greater Duckweed. Ward's proposal involves the re-neotypification of G.F.W.Meyer's 1818 type specimen named Lemna punctata which was apparently lost. Ward also proposed as the new type a different species that we know today as Spirodela intermedia.

  • Ward, D.B. 2011. "Spirodela oligorrhiza (Lemnaceae) is the Correct Name for the Lesser Greater Duckweed." J. Bot. Res. Inst. Texas 5 (1): 197-203.

Ward's LG Duckweed is the species that we have referred to as Spirodela (Landoltia) punctata in current taxonomic literature. If the original name (basionym) Lemna punctata G.F.W. Meyer is re-neotypified by Ward using the native South American species Spirodela intermedia W. Koch (1932), then the names Spirodela punctata G.F.W. Meyer (Thompson) and Landoltia punctata (G.F.W. Meyer) Les & D.J. Crawford will be applied to Spirodela intermedia and not LG Duckweed. The genus Landoltia was based on DNA analysis of Ward's LG Duckweed (see below) and not Spirodela intermedia. Therefore, the earliest correct name for LG Duckweed is Lemna oligorrhiza Kurz (1866) which was transferred to Spirodela oligorrhiza (Kurz) Hegelmaeir (1868). If a separate genus is created for LG Duckweed, Landoltia cannot be used.

In July 2012, I received an e-mail message from Dr. Thomas Rosatti, editor of the revised Jepson Manual (2nd Edition), asking my opinion on Ward's retypification. Since C.H. Thompson already neotypified this species as Spirodela punctata in 1898, Ward's retypification should really be a "re-neotypification." Since I wrote the section on duckweeds (subfamily Lemnoideae), adopting Ward's retypification would result in changes to several related species. In July 2012, I stated my opposition to Ward's proposal on my on-line Lemnoideae page on Wayne's Word. I also included a two-paragraph e-mail message from Dr. Elias Landolt, Zurich stating his opposition to the proposed retypification (see below). This quotation can be verified on the Internet Archive Wayback Machine dated 8 September 2012.

Spirodela punctata (Meyer) Thompson was named by C.H. Thompson in 1898 based on a collection from the 1938-1842 Wilkes Expedition, labeled Orange Harbor, Tierra del Fuego. Whether this collection actually came from the tip of South America is debatable. The parenthetical author G.F.W. Meyer described this species earlier as Lemna punctata from a type specimen collected in Guyana, South America in 1818. Unfortunately, Meyer's original type specimen was lost. According to Ward (2011), LG Duckweed does not occur in the areas where these collections were made: The Tierra del Fuego collection was mislabeled and the Guyana collection was not LG Duckweed. Futhermore, he states that the only native Spirodela in South America is S. intermedia. Since Meyer's type specimen was lost, Ward re-neotypified the species as Lemna punctata G.F.W. Meyer and he designated S. intermedia as the type. Thompson's binomial is still Spirodela punctata (Meyer) Thompson; however, this no longer refers to LG Duckweed. It is now the correct binomial for the South American Spirodela intermedia. The correct name for LG Duckweed now becomes Spirodela oligorrhiza (Kurz) Hegelmaier, a name published by Hegelmeier in 1868. Hegelmeier apparently never saw the South American specimens discussed above, so his name is probably based on the true LG Duckweed.

Ward's 2011 neotypification will make Landoltia a synonym of Spirodela and no longer available for the intended LG Duckweed. The restoration of separate generic status for LG Duckweed now known as Spirodela oligorrhiza (Kurz) Hegelm. will require the creation of a new genus name. The binomial Spirodela punctata (Meyer) Thompson will now refer to the South American species known as Spirodela intermedia W. Koch. By neotypification the name Landoltia becomes a synonym of Spirodela intermedia.

Quoted E-Mail Message From Dr. Elias Landolt

According to E. Landolt (Personal Communication, 2012), the name change proposed by Ward is untenable. This quotation can be verified on the Internet Archive Wayback Machine dated 8 September 2012.

    "I think this problem cannot be solved definitely. The main problem is the fact that it is not possible to decide which species Meyer was describing under the name of Lemna punctata. Certainly, it has to be a species of the genus Spirodela sensu lato because we don't know any other species within the Lemnoideae with pigment cells ("punctata"). The description of Meyer is very rudimentary. I could not find any herbarium specimen collected by Meyer. His description could concern Spirodela oligorrhiza, Spirodela intermedia or Spirodela polyrrhiza. I collected all of these species in northern South America. The description fits best for Spirodela oligorrhiza because it mentions 2-to 3 roots per frond. Most individuals of S. oligorrhiza in nature have 2 to 5 roots. S. polyrrhiza and S. intermedia mostly have more than 8 roots (up to 18). Only very rarely and only in very young fronds they show less then 5 roots. L. punctata was collected by Meyer in Guyana. On the other side, S. intermedia is known from the neighbouring state Surinam and surely is indigenous in the region. S. polyrrhiza and S. punctata might be introduced to South America. Today, S. punctata is frequent in the regions of Rio and Sao Paulo, in Venezuela, Colombia and Ecuador. I have collected S. polyrrhiza in Colombia and Ecuador. Even if S. punctata is introduced into South America it is not known at which year the introduction took place for the first time. It looks like S. punctata would be easily distributed by ship from harbour to harbour and from there by bird to places within a continent."

    "I can understand that Thompson choose a new type for Lemna punctata. The correctness of his decision is not disputed. I checked the neotype the collection of Wilkes from copies in four different Herbara. It is clearly the species which is now called "punctata". It is not important if the material was collected in Orange Harbor or somewhere else. Because it is not possible and will probably never be possible to decide the identity of Lemna punctata with certainity it is not advisable to change the correctly published neotype of Thompson. If we change the type of L. punctata again we will have a terrible chaos in nomenclature. Therefore I am not following the proposal of Ward."

A. Landoltia punctata (Spirodela punctata = S. oligorrhiza); B. Lemna minuta. The upper surface of Landoltia punctata is clearly punctate (appearing pitted). In dead fronds these punctae show up as brown pigment cells composed of oxidized & polymerized quinones similar to brown, oxidized phenolic componds in sliced apples and potatoes. Duckweeds with 2-3 (5) roots and a punctate dorsal surface are undoubtedly Landoltia punctata. The punctate surface is undoubtedly why G.F.W. Meyer originally named this species Lemna punctata about 200 years ago.

Dorsal view of dried herbarium specimen of Landoltia punctata showing brown pigment cells (punctae) in subepidermal layer of plant body (frond). The image was taken through an Olympus compond microscope with a Sony W-300 digital camera. Pigment cells occur in the plant bodies of other species of Spirodela. They are also in some species of Wolffia and Wolffiella, but not in Lemna. In fact, the punctate species Wolffia brasiliensis (formerly W. punctata) was originally named after these pigment cells or punctae. Wolffia punctata has also been used for W. borealis, but the correct synonym is W. brasiliensis. Magnification 100x and 400x.

South American Spirodela intermedia (inset) superficially resembles S. polyrrhiza in size, shape and number of roots; however, it does not produce overwintering turions. In fact, it does not occur in the cold northern latitudes. In addition, 2-5 roots perforate the ventral lobe of basal prophyllum compared with only 1-2 roots penetrating the prophyllum in S. polyrrhiza. Because of their larger size, Spirodela species are sometimes referred to as "greater duckweeds." Landoltia punctata is smaller, and in my opinion, more conspicuously punctate. Inset from E. Landolt (1986): The Family Lemnaceae - A Monographic Study. Vol 1. Veroff. Geob. Inst. ETH, Zurich 71: 1-566.

My objection to Ward's proposed neotypification is based on two primary points. (1) He is neotypifying Meyer's lost type specimen with Spirodela intermedia. It is impossible to know with 100% certainty which species Meyer was describing under the name Lemna punctata back in 1818. It could have been the "LG Duckweed" that we know as Landoltia punctata (Spirodela punctata = Spirodela oligorrhiza), or it could have been another species of Spirodela such as S. intermedia. Why complicate this taxonomy based on speculation. (2) Cladistical analysis has clearly shown that Spirodela punctata belongs in a separate genus (Landoltia), otherwise the grouping of Spirodela with 3 species is paraphyletic. The trend in modern floras such as the Jepson Manual Second Edition (2012) is for consistent monophyletic groupings.

Part 2. A Review Of Ward's Proposed Re-Neotypification

Ward's re-neotypification of Lemna punctata has been reviewed by J.H. Wiersema of the USDA Agricultural Research Service, National Germplasm Resources Laboratory, Beltsville, Maryland.:

  • Wiersema, J. H. (2014), Application of the name Lemna punctata G. Mey., the type of Landoltia Les & D. J. Crawford. Plant Biology. doi: 10.1111/plb.12209.

Here are Dr. Wiersema's conclusions: "The re-neotypification of Lemna punctata G. Mey. by Ward (2011) is to be rejected on the grounds that it has neither been established unequivocally that the previously selected neotype differs taxonomically from the original concept of Meyer, nor that this neotype is in serious conflict with Meyer's protologue. S. punctata and Landoltia punctata, both based on Lemna punctata, remain the correct names in Spirodela or Landoltia for the widespread species sometimes known as S. oligorrhiza and the name S. intermedia remains correct for a related neotropical species."

  See Another Taxonomic Controversy Regarding Incorrect Type Specimens  

The undisputed authority on the taxonomy of duckweeds (Lemnaceae) is the late Professor Dr. Elias Landolt of the Geobotanical Institute, Zurich, Switzerland. I have corresponded with Dr. Landolt for 30 years dating back to my original interest in this family of minute flowering plants in the early 1980s. Dr. Landolt passed away last year (2013). Interestingly enough, his only published input regarding the proposed name change in Spirodela is the above quotation that appeared on my Wayne's Word Lemnaceae page in July, 2012: Lemnaceae: Taxonomy Of Lemnaceae Of Western North America. The following dedication appears on my Lemnaceae Page:

This Page Is Dedicated To Dr. Elias Landolt (1926-2013)

Although I never met him in person, I corresponded with Elias Landolt of the Geobotanical Institute in Zurich, Switzerland extensively during the past 30 years. In fact, he sent me aseptic cultures of numerous species that I grew and photographed at my home in San Marcos, CA. I could have never learned about duckweed taxonomy or published my articles without first hand observations of his marvelous specimens and his outstanding Monograph of the Lemnaceae. He was a brilliant scientist and was so willing to share his phenomenal knowledge. Elias Landolt was truly an inspiration in my life. I will miss him and I will never forget him. WPA, September 2013


19.  Coauthored Article About Wolffia In Southern Europe For Journal Botany Letters Volume 164, 2017

Wolffia columbiana from the Po River, northern Italy. Inset: These dried, pressed plants were the size of course ground pepper grains until they were hydrated; however, they did not fully resume their complete 3-dimensional shapes. This made 100 percent identification very difficult.

In 2016 I was asked by Dr. Nicola Ardenghi of University of Pavia to verify the identification of Wolffia columbiana samples from the Po River of northern Italy. This noteworthy collection of a New World Wolffia species in southern Europe led to a scientific paper published in a scholarly peer reviewed journal.

Nicola M. G. Ardenghi, Wayne P. Armstrong & Daniele Paganelli 2017
"Wolffia columbiana (Araceae, Lemnoideae): first record of the smallest alien flowering plant in southern Europe and Italy"
Journal Botany Letters Volume 164, 2017 - Issue 2
Pages 121-127 | Received 13 Feb 2017, Accepted 10 Apr 2017, Published online: 05 May 2017
  LINK TO PDF OF THIS ARTICLE Published In Journal Botany Letters Volume 164  

  WOLFFIA FROM THE PO RIVER OF NORTHERN ITALY Photographic Analysis Of Specimens  


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