Sunday, October 31, 2021

Gibasis pellucida (Tahitian Bridal Veil) Disambiguation


created: Oct. 30, 2021
updated: Oct. 31, 2021
Gibasis pellucida (forma I, II) and Gibasis geniculata
In this drawing we see the two forms of Gibasis pellucida: forma I (with large leaves), forma II (with smaller leaves). Both have glabrous leaves. On the upper right is the Gibasis geniculata, with fuzzy leaves.


In this article we are going to examine the taxons of Gibasis pellucida, Gibasis geniculata, Tradescantia multiflora, Tradescantia multifolia, Tripogandra multiflora and a vernacular name that connects all these which did bring a lot of confusion among the Commelinaceae plant community up until the time of writing.

Introductory information

In 1993 the plant with the common name Tahitian Bridal Veil was selling like crazy in the USA and Canada, and a little later in Europe. It was a fancy plant with small glabrous leaves, green on the upper part and purple on the underneath. With a dense foliage and abundance of white flowers, flowering almost non-stop, making it as such a very beautiful hanging plant to have. The initial scientific name that was assigned to this plant was Tradescantia multiflora (multiflorus: multi [many] + florus [flowers]). And by some growers the species epithet multifolia (folia: leaved) was used instead: Tradescantia multifolia, to describe its dense foliage. However, none of those botanical names were backed up with scientific literature. The Hortus Third concise dictionary of plants cultivated in the United States and Canada, had listed the scientific name Tradescantia multiflora as a synonym of Tripogandra multiflora (Swartz) Raf., Fl. Tellur. 2: 16 (1837) back in 1982 [1, 2, 3, 4]. But the problem of no citation that could connect the vernacular name Tahitian Bridal Veil to either of those botanical names was still an issue.

Then came L. Graf in 1978 and 1992 citing the taxon Tradescantia multiflora as a synonym of Gibasis geniculata (Jacq.) Rohweder. Then Robert E. Woodson reported in 1981 that what was sold as a Tahitian Bridal Veil was a selected form of G. geniculata and cited Tradescantia geniculata and Aneilema geniculatum (Jacq.) Woodson. The same author, Robert E. Woodson described in 1981 G. geniculata with hairless leaves, whereas Anthony J. Huxley in 1992 described G. geniculata as bearing villous (fuzzy) leaves. D. R. Hunt in 1986 associated Tahitian Bridal Veil with G. pellucida. but there was no citation of Tradescantia multiflora in neither of the Gibasis taxons (G. geniculata; G. pellucida).



Taxonomic evidence

Then at North Carolina State University Tahitian Bridal Veil plants were cultivated and examined in order first to validate their genus (Gibasis, Tradescantia, or Tripogandra) and secondary to distinguish their species. The growth habit of Tahitian Bridal Veil is creeping, with stems as slender as 1 mm in diameter, with asymmetrical leaves, ovate-lanceolate to lanceolate, acute to short acuminate, glabrate (somewhat glabrous), dark green above to dark reddish-purple below, having lateral veins, 24 mm long. The inflorescence is born from upper axils and is mostly terminal and stipitate, with cincinni free, binating above the stipe. And the stipe is green approx. 12 - 24 mm long. Tripogandra plants have flowers that are zygomorphic, sessile with fused cincinni and unequal stamens. Thus the Tripogandra genus was excluded.


Gibasis, Tradescantia, inflorescence, Commelinaceae research blog
Typical Gibasis (left) and Tradescantia (right) inflorescences.

Then the most easier task was to tell the inflorescence of Tradescantia in relation to that of Gibasis. In particular, the inflorescence of Gibasis has cyme bracts that are reduced to the point of appearing absent. Tradescantia on the other hand possesses large, spathaceous bracts[5].

The next step was to identify the correct species of Tahitian Bridal Veil within the genus Gibasis. D. R. Hunt provided in 1986 a revision of Gibasis that included a key to identifying the species[2]. In the Gibasis genus there are only three species that produce white flowers: G. geniculata, G. oaxacana and G. pellucida. G. oaxacana is easy to tell by her three to eight cincinni in an umbel and petiolate leaves spirally arranged. G. geniculata is distinguished easily by her paired cincinni; sessile, densely villous leaves that are distichate (2-ranked on the stem). G. pellucida is easily distinguished by paired cincinni, sessile glabrate leaves that are also distichate.

Gibasis oaxacana vs Gibasis pellucida vs Gibasis geniculata
G. oaxacana vs G. pellucida vs G. geniculata[2]




Gibasis pellucida (forma I) with larger leaves
Gibasis pellucida (forma I) with the larger leaves.
photo from Erica Jane

Two forms of Gibasis pellucida

There have appeared among Commelinaceae plant collectors two forms of G. pellucida. Gibasis pellucida (forma I) with large leaves and thicker stems and Gibasis pellucida (forma II) with small leaves and slender stems up to 1 mm in diameter.
In particular, these two forms have enough morphological characters to recognize them as different taxa, not at species level, but as subspecies or varieties. But, extensive field collection and characterization is needed also to confirm this preassument[6]. As already described in the revision papers above, both plants have glabrate (somewhat smooth) leaves. Only the G. geniculata has clearly visible villous (fuzzy) leaves.

Gibasis pellucida (forma II) with the small leaves.
Gibasis pellucida (forma II) with the small leaves.



P.S.: the article will be updated in the following days with photos from the two different forms of Gibasis geniculata. So stay tuned.


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References (main sources: 1, 2)
6. Communication with Spanish botanist Pere Fraga Arguimbau.
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Wednesday, July 14, 2021

Tradescantia zebrina 'Velvet Hill' - yet another mislabeled Tradescantia

Wrong label: that is not a zebrina. And... 'Hill' again? Gimme a break with all that hill-color-make-up plant tags. New plant enthusiasts expect that the nurseries know what they are selling.


Introduction

Listed for sale from a Dutch trading platform[1] as Tradescantia zebrina 'Velvet Hill' is this plant (shown in the image above). Yet another hill-color-make-up tag. This time not from the same Dutch nursery that circulated all those hill-color-make-up plant tags. The plant we are discussing here listed for sale as Tradescantia zebrina 'Velvet Hill' is simply a Tradescantia sillamontana. Tradescantia sillamontana is a botanical species that was first described by Matuda back in 1955[2, 3]. The common names for Tradescantia sillamontana are: White Velvet, Cobweb Spiderwort, White Gossamer, Hairy Wandering Jew. Thus the proper way to write the full name of the plant with its common names is:
Tradescantia sillamontana (White Velvet, Cobweb Spiderwort, White Gossamer, Hairy Wandering Jew) or just use one from the common names, usually the White Velvet.
A more detailed and scientifically correct way to write the full name, including the botanist that described it, the year and also its synonyms is the following:
Botanical name: Tradescantia sillamontana Matuda (1955)
Common names: White Velvet, Cobweb Spiderwort, White Gossamer, Hairy Wandering Jew
SynonymsTradescantia pexata H.E.Moore[3]

Correct botanical information

Regarding that Tradescantia zebrina 'Velvet Hill' plant tag now. From where should I begin... first of all, as I have already stated above, T. sillamontana is a botanical species, not a  man-made cultivar, and in botanical species there are no cultivar tags involved. The way the 'Velvet Hill' is written indicates a cultivar. Secondly, this is a T. sillamontana, not a zebrina. FYI 99.8% of the zebrina's have the typical dual, silvery/green stripes, as seen in the wild T. zebrina type and other more common zebrina cultivars. The only zebrina's that completely lack stripes are the rare T. zebrina var. flocculosa and the T. zebrina var. purpusii. Observe their differences in the following pictures.

The typical dual silvery/green stripes seen on most Tradescantia zebrina plants. These stripes are reflecting the surrounding light, therefore sometimes they seem greener and other times more silvery.

Tradescantia zebrina var. flocculosa. One of the two zebrina's that lack stripes.

Tradescantia zebrina var. purpusii: the second zebrina variety that lacks the typical zebrina stripes




What do Plant Certificates actually certify?

Now that there is a basic understanding, let's come again to the image of that Dutch trading platform. If we zoom-in at the lower left part of the image, we can see three logos.







← FYI that number identifies the seller/nursery (this one in this image is a random one from the internet, just for reference)

























All three of these logos are plant certificates. The first one is a plant certificate from Florensis[4], a company located in the Netherlands. From their About page we read:
"Florensis is an innovative, second-generation family business from Hendrik-Ido-Ambacht (Netherlands), founded in 1941 under the name Hamer Bloemzaden. The company has a proven track record worldwide as breeder and as supplier of starting material for professional growers.With 2,000 dedicated and highly-skilled employees from the Netherlands, Europe and far beyond, Florensis produces over 1 billion young plants from seed, cuttings and tissue culture every year."













The second plant certificate comes from GGN Certified Farming[5], a company located in Germany. From their About page we read:




















"The GGN label stands for certified, responsible farming and transparency. It is designed to help guide you in your day-to-day grocery shopping. Transparency is at the heart of our label – Our label connects you to the roots of your food and plants. And by promoting certified responsible farming that benefits farmers, retailers, and consumers around the globe, we support worldwide sustainable development for the good of future generations and our planet."

And the third plant certificate comes from On the way to PlanetProof[6], a company located in the Netherlands. From their FAQ page we read:











"On the way to PlanetProof is a quality mark for products and services. On the way to PlanetProof is available for potatoes, vegetables, fruit, dairy, eggs, flowers, flower bulbs, trees and plants and processed products."






If we visit again the specific page of FloraXchange we see on the right hand side the specific nursery that sells this plant. It comes from Bunnik Plants[7], a nursery located in the Netherlands.



From their Contact page we read:
"The Bunnik Plants team consists of enthusiastic team players who have a good dose of entrepreneurial spirit and a professional attitude."

Conclusion

FloraXchange is a trading company that connects the buyers with the nurseries, the plant breeders and the like. They don't sell plants themselves, yet they are involved in the horticultural business and they list plants and plant names on their website. Even if they did not begin as "plant-people" they ought to know what they list in their own website. After all, they proudly present three plant-certificates there, and the average plant buyer assumes they know what they are listing is the correct information.

Bunnik Plants though have the greater share of responsibility, since they are a nursery and as it seems  (from the FloraXchange website about the specific product) it's the nursery from which that plant tag was circulated. An average buyer that is going to buy from them assumes that they are buying a plant with the correct label. What if that buyer already had the Tradescantia sillamontana? What if 500 buyers already had the Tradescantia sillamontana?... Then all these consumers have paid for the same plant twice. And what if we see a new plant tag in the future - something like Tradescantia fluminensis 'Velvet Queen' - describing the same plant, a Tradescantia sillamontana? Are then these people going to pay a third time for the same plant?... Can you realize where it leads to?

Personally I don't think that was just a case of a single mislabeled plant tag. By checking their plant catalog at ISUU[8] I see more plant tags that are mislabeled, such as the Philodendron White Wave → actually a Philodendron 'Birkin'. I have seen this also as Philodendron White Measure.


References
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Sunday, January 10, 2021

Variegated Tradescantia zebrina plants

updated: July 25, 2021
Tradescantia zebrina var. tikal
A T. zebrina with natural variegation that does not revert


Variegation in botany : definition

(1) Variegation in general. Variegation simply refers to a variety of color, usually of a leaf or flower, but stems/trunk, branches and even seeds can be variegated as well. In most cases, the cause of the variegation is difference in the amount of pigment (often chlorophyll) in the plant's structure, anywhere from a total lack, resulting in white to pale yellow coloration (depending on the quantity of the xanthophyllic pigments in the leaf--those without any xanthophyllic contribution will be completely white), to a subtle difference, resulting in various shades of green or another color if another chemical coloration is involved. Plants with petals, carpals or leaves that have multiple colors, even if none are white, are still called variegated. Sometimes the variegation is only a variation in the amount of anthocyanins (usually the basis for most red, purple or pink coloration) and there is no lack of chloroplast output. And sometimes it is a combination of both, as one can see in the incredible variation of colors in the bromeliads, Coleus, Tradescantia cultivars and Huechera varieties.

(2) Yellow and white variegation. Variegated leaves with yellow or white variegation occur rarely in nature. Species with these variegated individuals are sometimes found in the understory of tropical rainforests, and this habitat is the source of a number of variegated houseplants.

(3) Viral induced variegation. Infection by a virus can also be a cause of variegation, and this has been studied by scientists, such as in case of the Tobacco Mosaic Virus. in the Commelinaceae family, a virus-induced variegation is believed to be the cause for the yellow variegated Tradescantia cerinthoides aka: Tradescantia cerinthoides f. glabra 'Aureovariegata'.

The variegated zebrinas'

Currently there are six variegated zebrinas both with natural variegation that doesn't revert, and there are also cultivars with white or yellow variegation, where in two of them the variegation will be lost when they are kept in low light for a prolonged period of time.

Tradescantia zebrina - table listing the variegated varieties and cultivars
Tradescantia zebrina with natural variegation Tradescantia zebrina with white/yellow variegation (cultivars)
Tradescantia zebrina var. mollipila Tradescantia zebrina var. discolor 'Multicolor'
Tradescantia zebrina var. mollipila 'Purple Plush' Tradescantia zebrina 'Quadricolor'
Tradescantia zebrina var. tikal Tradescantia zebrina 'Danny Lee'

The zebrinas' with naturally occurred variegation do not lose their variegation. The cultivars with white/yellow variegation may revert back to green when kept in low light, with the exception of the Tradescantia zebrina 'Quadricolor', since most of the times, the seemingly variegated green branches will develop again the variegated pattern, when exposed in bright light. More information on each of these Tradescantia zebrina plants (and more) can be found on another post: Tradescantia zebrina : varieties, cultivars, hybrids.

Tradescantia zebrina var. discolor 'Multicolor'
this highly variegated cultivar will unfortunately lose its variegation
and it will revert to a discolor zebrina with faint silver stripes on the green leaves,
when exposed in much lower light for a prolonged period of time.

Tradescantia zebrina var. discolor 'Multicolor' branch with almost complete lack of chlorophyll.
Without chlorophyll plants cannot grow on their own.
They can only grow for some time when attached to the mother plant.


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Saturday, December 26, 2020

Tradescantia boliviana

Updated: Sept. 22 2021
Tradescantia boliviana: the spectacular inflorescence (credits of the photo to Stefan Neuwirth),
and a rooted cutting.

Family: Commelinaceae
Accepted nameTradescantia boliviana[1, 2, 3]
BasionymMandonia boliviana[1, 2, 3]
SynonymsMandonia bolivianaSkofitzia bolivianaTradescantia ambigua var. pilosula[1, 4]
Heterotypic synonymTradescantia ambigua var. pilosula[1]
Homotypic synonymSkofitzia boliviana[1]
Leaf-texture: pilosulus (somewhat fuzzy)

The Tradescantia boliviana is a relatively recently discovered botanical species in the Commelinaceae family, native to Argentina, Bolivia, Brazil, Paraguay and Peru. It was firstly described in 2004 (Jason R. Grant) as a new species, with distinctively different characteristics than the Tradescantia ambigua[2, 3].

Description
The small narrow and pilosulus (somewhat fuzzy) leaves have a thin orange border and are slightly jagged at the edge of the leaf. The edge of the leaves is also recurvifolius (having a wavy form; see last image for more) and the arrangement of the leaves is alternate, one leaf per node and at an angle approx 90°.

It’s a summer growing perennial, which needs strictly and completely a dry winter dormancy. It needs full sun to remain upright and then masses of medium sized fuchsia triangular flowers appear along the shoots, very attractive.


Photographic material

Summer growth and colors.

Summer growth and colors.

Summer growth and colors. This plant has thick tuberous roots


Tradescantia boliviana: winter growth. The small narrow leaves are slightly fuzzy
with an orange border on the edge of the leaf, when exposed in bright light.

Tradescantia boliviana: winter growth. Small narrow fuzzy leaves with thin purple stems.


Winter growth.


Some tips on identification: The edge of the leaves is jagged and also recurvifolius (having a wavy form [1]).
And the arrangement of the leaves is alternate, one leaf per node and at an angle approx 90° [2].






References
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Friday, December 25, 2020

Tradescantia hirta


Tradescantia hirta

hirtus, -a, -um refers to the hairiness of the plant.

Just like every other Tradescantia, they are easy to get them to root
in water, in sphagnum moss, or directly into the soil.


Tradescantia hirta is a botanical species from NE Mexico, in the family Commelinaceae. Its characteristic are the thin stems covered with hairs. And also, it's a rarely seen Tradescantia species that forms tear-drop bulbs that sit on top of the soil, in clusters.
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Thursday, December 24, 2020

Tradescantia buckleyi

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Tradescantia buckleyi: in bloom, at her winter colors.

Here she is with her natural greyish colors (exposed in bright light during summertime).
When exposed in lower light (during winter) the foliage turns green,
but when exposed again in bright light her natural greyish colors appear again.


Tradescantia buckleyi is a botanical species (natural variety) in the Commelinaceae family.



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Tuesday, December 15, 2020

Tradescantia zebrina var. tikal


Tradescantia zebrina var. tikal : a naturally occuring variety near Tikal, Mexico
Tradescantia zebrina var. tikal: the rarest and
the most beautiful zebrina, is making it difficult for us.


updated: 10 August 2021
The Tradescantia zebrina var. tikal is a naturally occuring variety near Tikal, Mexico. It resembles somewhat to the mollipila but the leaves are larger, less round, mostly in arrow-shape, with vivid purple stripes on both sides of the leaf.

Is this yet another infraspecific?

Since this is a naturally occurring plant with such distinct pattern, it seems so. It's just that the plants in the genus Tradescantia are proliferating and the botanists can't catch up with their classification. At the time of writing, there are three accepted infraspecifics in the zebrina genus at the POWO website:
  • Tradescantia zebrina var. flocculosa (G.Brückn.) D.R.Hunt
  • Tradescantia zebrina var. mollipila D.R.Hunt
  • Tradescantia zebrina var. zebrina
Tradescantia zebrina accepted infraspecifics

Therefore, I believe what we have here is a pending classification.
By the way, I have seen this plant written with single (or even double) quotes, but the single quotes are indicating a cultivar, not a naturally occurring variety.



This naturally occurring zebrina variety was rescued from its natural habitat in Mexico, but unfortunately it carries a kind of bacterial infection. This infection is a rare case, since it is mostly active during winter but with the warmer summer temperatures the plant seems to be doing fine. This is quite the opposite from what we see in most of the bacterial infections, which are most active during warmer temperatures, just the opposite from what we have here. This infection doesn't seem to be contagious, it's just that during low temperatures the plant loses its colors and it grows slower (mostly green) with a few (the typical zebrina) stripes here and there with a broken pattern. When exposed again to the higher temperatures in summer, it appears to grow normal again. At the moment, everyone that has a Tradescantia zebrina var. tikal in their collection, has the same infected clone. Experienced Commelinaceae collectors have not managed to determine (and reverse) the course of that viral infection. TS (Tissue Culture) might be an option to try and clear this natural variety from that viral - yet harmless - infection. The best solution however - if it is possible - would be to start all over with a freshly new specimen - pathogen free - from another location.


This is how the plant looks in the growing season, seemingly healthy.


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