Three different gentian groups have been called Lisianthus:
1. The genus Lisianthius,
which has it as its Latin genus name.
2. The genus Chelonanthus
and related genera, which previously belonged
to a genus called Lisianthus or Lisyanthus,
together with the species of Lisianthius.
3. The genus Eustoma, which
is called lisianthus in English.
This is the story:
Browne described the genus Lisianthius from the Caribbean, and
Linnaeus soon changed the spelling to Lisianthus. Soon after, Aublet
described a genus named Lisyanthus from French Guiana.
This was either a new genus with a very similar name to an existing genus,
or he changed the spelling for Lisianthius again. Scientists don't
know what the intention was, but the species that belong to Aublet's group
are not related to Browne's species, so they formed different groups.
However, most botanists treated the whole group of species as
for centuries, while adding more species. But according to naming rules
Botanical Code), the spelling of the oldest name had to be followed,
so today Lisianthius is the correct spelling.
In the meantime, the genera Irlbachia
and Helia had been described from
Brazil by Martius (1827). These two genera are related to the genera
(which were formerly sections of Lisianthus/ Lisyanthus, and were
excluded from it in the mid- to late 1800s).
The Lisyanthus species of Aublet, were put into Chelonanthus.
Several authors (for example Steyermark) did not accept the segregated genera and used the
name Lisianthus for species from continental South America into the
All Lisianthus species from South America (not Central American and
Caribbean) were excluded from Lisianthius and put in Helia
by Kuntze in late 1800s (including species now in Irlbachia, Macrocarpaea,
Chelonanthus and Calolisianthus). Nobody really cared what
Kuntze had done, however. Most people after that continued with the same
segregate genera as earlier. In 1985, Maas and his collaborators combined Chelonanthus,
Helia, and Calolisianthus with Irlbachia, creating a
much larger Irlbachia - the only
problem was that Helia should have been the name of this large
genus, not Irlbachia, because of rules of priority (Kuntze had
already decided that Helia had priority over Irlbachia).
And now today, with molecular data and phylogenetic methods, we know more about how species are related. The Caribbean and Central American
Lisianthius species is a distinct genus in the tribe
Potalieae, whereas the continental South
American (and a few outliers) species should be put into the genera
Chelonanthus, Calolisianthus, Helia, and Irlbachia,
respectively, which are part of tribe Helieae.
Nobody uses the spelling Lisianthus or Lisyanthus anymore,
except as an English name for a non-related gentian (see below).
And then there is Eustoma - a
Caribbean/ southern United States genus of 2-3 species that are commonly
cultivated. The common name for one of the
species is lisianthus, and as far as I know it has never had the Latin
name Lisianthus (or any other spelling thereof). It is unknown how
this English names was given to this plant because Eustoma is not
very similar to either Lisianthius or the South American
Chelonanthus-relatives, and belongs to a different tribe, the
Chironieae. Another common name for Eustoma
is prairie gentian.
M. F. 1775. Histoire des plantes de la Guiane Françoise, vol. 1. P.-F.
Didot, London & Paris.
P. 1756. The civil and natural history of Jamaica in three parts, ed. 1.
T. Osborne & J. Shipton, London.
C. E. O. 1891. Revisio generum plantarum, vol. 2. Arthur Felix, Leipzig.
C. F. P., von. 1826-27. Nova genera et species plantarum quas in itinere
per Brasiliam, vol. 2. V. Wolf, München. IMAGES
P. J. M. 1985. Nomenclatural notes on neotropical Lisyantheae
(Gentianaceae). Proc. Kon. Ned. Akad. Wetensch., Ser. C, 88: 405-412.
L. & V. A. Albert. 1998. Lisianthius
(Gentianaceae), its probable homonym Lisyanthus,
and the priority of Helia over Irlbachia as its substitute. Harvard Pap. Bot. 3: 63-71.
L., J. W. Kadereit, J. Klackenberg, S. Nilsson, M. Thiv, K. B. von Hagen,
& V. A. Albert. 2002. Systematics, character evolution, and
biogeography of Gentianaceae, including a new tribal and subtribal
classification. Pp. 21-309. In: L. Struwe & V. A. Albert (eds.),
Gentianaceae: Systematics and Natural History, Cambridge University Press,
© Lena Struwe, 2007