Nomenclature ofTahitian BridalVeil

Paul R. Fantz and

Paul Nelson

Additional index words. floriculture,nomenclature, taxonomy,Commelinaceae, Gibasis, Tripogandra,Tradescantia

Summary. Tahitian bridal veiltraditionally has been assigned thescientific name of Tradescentiamultiflora (or Tradescentia multifoilain the floricultural industry. HortusThird lacks the name Tahitian bridalveil. Other references also lack thisvernacular name or assign this planteither to Tripogandra or Gibasis as G .geniculata or G. pellucida. Thus,modern literature references suggestthree potential scientific names. Plantsof Tahitian bridal veil were examinedmorphologically. A description wasprepared and compared to literaturedescriptions of the taxa involved.Results indicated that Tahitian bridalveil was misidentified at least twice byearlier authors and that the correctname for Tahitian bridal veil is G.pellucida.

I n 1993, 43 million foliageand flowering hanging bas-kets were grown in the United

States and marketed as floriculturalcrops at the wholesale level for $203million (U.S. Dept. of Agriculture,1994). One of these crops used exten-sively as a hanging basket plant in theUnited States, Canada, and Europe isTahitian bridal veil or bridal veil (Fig.1). Several factors contribute to itspopularity. Tahitian bridal veil is propa-gated easily from terminal and sec-tional stem cuttings that are rooted

Professors, Department of Horticultural Science, NorthCarolina State University, Box 7609, Raleigh, NC 27695-7609.

Research Project NC0 6104 funded in part by the NorthCarolina Agricultural Research Service, Raleigh, NC27695-7643, Use of nursery and trade names in thispublications does not imply endorsment by the NCARS ofthe nurseries or the products mentioned nor criticism ofsimilar ones not mentioned. The cost of publishing thispaper was defrayed in part by the payment of pagecharges. Under postal regulations, this paper thereforemust be hereby marked advertisement solely to indicatethis fact.

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directly in the hanging basket. Envi-ronmental requirements are moder-ate; the plant requires medium lightintensity and temperatures of 13 to21C (John Henry Company, 1977).Growth is rapid and the creeping formproduces a pendulous mound, whichis ideal for a hanging basket. The deepgreen upper surface and purple under-sides of leaves blend nicely with many,small, brilliant white flowers to givethis plant exceptional sales appeal.

An inquiry by growers was madeto faculty members at North CarolinaState Univ. regarding the correct sci-entific name for Tahitian bridal veil.These growers indicated that the namemay be Tradescantia multifolia, butthey couldn’t find this name in a refer-ence. Problems encountered by us insearching the literature for a correctscientific name led to a morphologicalexamination of Tahitian bridal veil toascertain the correct genus to which itshould be assigned.

Taxonomic literatureThe name Tahitian bridal veil is

lacking in Hortus Third (Liberty HydeBailey Hortorium, 1976) and otherreferences that include floriculturalcrops (Bailey, 1917, 1949; Graf, 1978,1982; Hessayon, 1991; Larson, 1992;Perry, 1974). Rathmell (1980) statedthat Tahitian bridal veil was Trades-cantia multiflora (no authority given).John Henry Company (1977) cited

Fig. 1. Habit of Tahitian bridal veil as a hanging

Tahitian bridal veil as Tradescantiamultiflora Swartz, a name similar to agrower’s name of Tradescantia multi-folia. These two epithets contain thebasic Latin roots -folius and -florus,translated by Stearn (1992) as leavedand flower, respectively. These twoLatin root words also appear in otherepithets (e.g., grandifolia and grandi-flora, parvifolia, and parviflora). Theseepithet pairs are similar in length, spell-ing, and appearance. Thus, each mem-ber of the pair is confused commonlywith the other member by students inplant material courses and members ofthe landscape, nursery, and floricul-tural industries.

Hortus Third lacked the nameTradescantia multifolia, but cited thename Tradescantia multiflora as a syn-onym of Tripogandra multiflora(Swartz) Raf. Everett (1982), andHuxley (1992) listed Tripogandramultiflora with a brief description thatcould fit bridal veil. However, neitherthe vernacular name Tahitian bridalveil nor Tradescantia multiflora wascited under either Tripogandra Raf. orTradescantia L. Graf (1978, 1982)cited Tradescantia multiflora as a syn-onym of Gibasis geniculata (Jacq.)Rohw. Hortus Third reported G.geniculata as sometimes cultivated as alaboratory plant, but not offered in thetrade.

Everett (198 1) reported Tahitianbridal veil as a selected form of G.

basket floricultural crop.

Table 1. Morphological comparison of three gemra of Commelinaceae.

Character Tripogandra Tradescantia Gibasis

InflorescenceStipe Lacking Lacking PresentCincinni Fused Fused FreeBracts Inconspicuous Conspicuous Inconspicuous

FlowersSymmetry Zygomorphic Actinomorphic Actinomorphic

StamensLength Long and short Subequal SubequalFilament Three curved Straight StraightTrichomes Bearded or glabrous Bearded BeardedConnective Narrow Broad Triangular

Fig. 2. Axillary inflorescence of Tahitian bridal veil with its paired, stalked, free cincinni.

geniculata and cited Tradescantiageniculata Jacq. and Aneilema genic-ulatum (Jacq.) Woodson in synonymy,but he did not use the name Trades-cantia multiflora. Also cited was aclose relationship of G. geniculata withG. oaxacana D.R. Hunt. Huxley(1992) associated the name bridal veilwith G. pellucida (Martens & Gal.) D.Hunt. and noted that, under the entryG. geniculata, it is often confused withG. pellucida in cultivation. Everett(1981 ) described G. geniculata withhairless leaves, whereas Huxley ( 1992)described G. geniculata as bearing vil-lous leaves.

Hunt (1986) associated bridal veilwith G. pellucida but did not cite Tra-descantia multiflora in synonymy, noris Tradescantia multiflora cited in syn-onymy with G. geniculata.

Although Tahitian bridal veil is awell-known plant in the floriculturaltrade, its correct scientific name is notclear. Literature references suggest thefollowing choices: 1) Tripogandra mul-tiflora, 2) G. geniculata, or 3) G. pellu-cida or G. oxacana. Which name shouldhorticulturists accept?

Taxonomic evidencePlants of Tahitian bridal veil (Fig.

1) obtained from commercial sourceswere grown under greenhouse condi-tions at North Carolina State Univ.,examined, and described morphologi-cally from first-hand observation. Thedescription presented below was thetaxonomic evidence we used for com-parison with literature descriptions todetermine the correct identification ofTahitian bridal veil.

“Tahitian bridal veil.” Stems creepingto decumbent, branching and rooting atthe nodes; twigs slender, terete, to 1 mmdiam., glabrate with scattered minute

trichomes and one conspicuous row oferect trichomes (ca 0.1–0.2 mm) fromnode to node on the opposite side fromthe leaf blade above. LEAVES asym-metrical, nearly distichate on twig,subsessile on the sheath, 1–5 cm long,0.3–1.6 (3) cm wide, blade ovate tonarrowly oblong to ovate–lanceolate tolanceolate, entire, acute to short acumi-nate, obliquely cordate, glabrate, darkgreen above, green to reddish-purplebelow, lateral veins 2-4/side; sheathclosed, striate, 24 mm long, sericeous-ciliate on upper edge (trichomes 34mm), ascending-spreading sericeous (tri-chomes 14 mm) on the surface. IN-FLORESCENCES borne from upperaxils and seemingly terminal, stipitate.Cincinni free, binate above stipe. Stipegreen, 12–24 mm long. Peduncular

bracts 2, membranous, narrow concave-lanceolate around peduncle, acute, seri-ceous, 1.8–2.5 mm long, ca 0.3–0.6 mmwide. Peduncles green, 12–17 mm long.Bracts inconspicuous, imbricate, ovate,membranous, acute, to 1 mm long, ca0.7–0.8 mm wide. Pedicels in flowerpurple to blackish-purple, 7–14 mm long.Bracteoles 2, ovate, translucent, to 1mm long. FLOWERS with only oneopen per cincinni. Sepals 3, green, ellip-tic-navicular, weakly keeled, acute, 2–2.2 mm long, 1 mm wide. Petals 3,white, ovate-orbicular, broadly obtuse,3.64 mm long, 3.54 mm wide at base.Stamens 6, subequal, white, beardedbasally and near apex; filaments 2.5-2.8mm long; anthers versatile, yellow, con-nective deltoidal; trichomes dense,spreading in a rosette pattern, monili-form, basal set 1.5–2 mm long, apical setca 0.5–0.8 mm below anthers, to 1 mmlong. Pistil white; ovary 3-locular, ca0.6–0.8 mm long; style slightly exertedbeyond stamens, 3 mm long; stigmacapitellate. Fruits not observed.

Taxonomic identificationThe first step in identification was

to determine the genus to which Tahi-tian bridal veil should be assigned.There were three possible genera:Tripogandra, Tradescantia, a n dGibasis. Characters used for segregat-ing the genera are compared in Table1. Tahitian bridal veil is not a

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Fig. 3. Stamens of a flower of Tahitian bridal veil bearded basally and apically.

Tripogandra (Greek tri-, three; pogon,beard; andros, male). Members of thisgenus differ from Tahitian bridal veilby possessing zygomorphic flowers;sessile, fused cincinni; a narrow antherconnective; and unequal stamens, withthe inner whorl of three stamens bear-ing a longer filament that curves to beerect in front of the upper petal. Tahi-tian bridal veil is not a Tradescantia(named in honor of John Tradescant,a British naturalist). Members of thisgenus differ by possessing sessile, fusedcincinni and paired, conspicuous, en-larged leaf- or boat-like bracts sub-tending the inflorescence. Gibasis(Latin gibbus, swollen; Greek basis,base; reference to gibbous base of se-pals) is distinguished by the free cincinnisubtended by a pair of bracts and borneon a prominent stipe (Fig. 2) and thebroad triangular anther connective.Tahitian bridal veil has all of thesecharacteristics; thus it is a Gibasis.

The second step in identificationwas to identify the correct species ofTahitian bridal veil within the genus.Hunt (1986) provided a revision ofGibasis that included a key to species.Most species have flowers purple toviolet-blue to pink, not white. Thereare three white-flowering species.

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Gibasis oaxacana is distinguished eas-ily by bearing three to eight cincinni inan umbel and petiolate leaves spirallyarranged. Gibasis geniculata is distin-guished easily by having paired cincinni;sessile, densely villous leaves that aredistichate [2-ranked]; glandular-pu-bescent stipes; and filaments beardedonly at the base. Gibasis pellucida isdistinguished easily by paired cincinni,sessile glabrate leaves that are distichate,eglandular stipes, and filamentsbearded basally and above (Fig. 3).Tahitian bridal veil keys out easily to G.pellucida, and our description, basedon first-hand observations, agrees withHunt’s description of this species. Thus,we agree with Huxley (1992) from ourtaxonomic investigation that the cor-rect name for Tahitian bridal veil is G.pellucida (Martens& Gal.) D. Hunt.

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