Grayum, M.H., B.E. Hammel, and Q. Jiménez Madrigal. 2012. Validation te scientific name for the Tahitian lime.
Phytoneuron 2012-101: 1-5. Published 26 November 2012. ISSN 2153 733

VALIDATION OF A SCIENTIFIC NAME FOR THE TAHITIAN LIME

MICHAEL H. GRAYUM, BARRY E. HAMMEL
Missouri Botanical Garden

.O. Box
St. Louis, Missouri 63166-0299, U.S.A.
1 b 1 1

michael org, barry! org

QUiRICO JIMENEZ MADRIGAL
Unidad de Gestion Ambiental
Empresa de Servicios Publicos de Heredia
Heredia, Costa Rica
qjimenez@esph-sa.com

ABSTRACT
The name Citrus latifolia Tanaka, commonly used for the economically important Tahitian
lime, is found to have been invalidly published, without a Latin description or citation of any
basionym. Likewise, publications referring to a presumed basionym, C. aurantiifolia (Christm.)
Swingle var. latifolia Tanaka ex Yu. Tanaka, do not effect valid publication for that entity nor
reference to any synonym that could be used. A diagnosis and type citation are here provided to
validate a scientific name for the Tahitian lime, Citrus <Jatifolia Tanaka ex Q. Jiménez.

KEY WORDS: Citrus latifolia, limon mesino, Persian lime, Rutaceae, Tahitian lime.

Citrus latifolia Tanaka is the name in current use for a species of economic importance
commonly known in the English-speaking world as the Persian or Tahitian lime (see, ¢.g., Mabberley,
2008). However, in the process of editing the Rutaceae treatment for the Manual de Plantas de Costa
Rica, we have found that C. latifolia Tanaka (1951: 140), often cited as C. Jatifolia (Tanaka ex Yu.
Tanaka) Tanaka, was published without a Latin description or mention of any basionym and, as such,
is invalid and cannot be considered as either a new taxon name or a new combination.

The oft-cited parenthetical authorship refers to a presumed basionym, Citrus aurantiifolia
(Christm.) Swingle var. latifolia Tanaka ex Yu. Tanaka (1948). The ostensible protologue of the
varietal name includes extensive Japanese text, a detailed illustration, and a bibliography, but apart
from binomials and trinomials, no Latin, which was required at the time (validation by means of
illustrations was only permitted before 1908; see McNeill et al., 2006: Art. 42.3). Tanaka (1948: 57,
60) cited a specific page in Tanaka (1938), which act could conceivably have resulted in the
validation of the name, but the last-mentioned paper also includes no Latin text, merely the name
“Citrus aurantifolia Swingle var. latifolia Tanaka” in a skeletal list, with a few Japanese characters.

Consulting all the other references we could track down that might contain or lead to a
validly published version of either of these names (¢.g., Tanaka 1932, 1939), we came up empty-
handed. Furthermore, we know of no synonym that could be used in place of Citrus </atifolia.
Therefore, in order to provide a valid name for a species of Citrus to be treated in the Manual de
Plantas de Costa Rica and which is an important commercial crop in Costa Rica (where it is
commonly known as limon mesino or limdén persa) and many other parts of the world, we here
provide a diagnosis and cite a type specimen for Citrus <Jatifolia (now generally acknowledged as a
hybrid involving C. <aurantiifolia), the name first used by Ty6zabur6 Tanaka (1885-1976):

Grayum, Hammel, and Jiménez Madrigal: Scientific name for the Tahitian lime 2

CITRUS xLATIFOLIA Tanaka ex Q. Jiménez, sp. nov. TYPE: COSTA RICA. Heredia: Cantén
de Santo Domingo. Dtto. Tures. Calle La Rinconada, en cafetales y lotes por el Rio Tures,
9° 60' N, 84° 04' W, 1200 m, 20 Feb 2006, B. Hammel & I. Pérez 24125 (holotype: MO,
isotypes: CR, INB). Figures 1-3.

Similar to Citrus xaurantiifolia (Christm.) Swingle (Key lime, lime, limon criollo, etc.) but
differing by its lack or near lack of thorns and larger fruits (5.5-8 x 6-7.5 cm, vs. 4-6 x 4-5 cm) with
a thicker rind (3-7 mm, vs. 1-3 mm), lacking seeds, and with less acidic, non-bitter juice.

Figure 1. Citrus latifolia. Close-up of flowering branch showing buds, open flower, and young fruit (Hammel
& Pérez 24125); inset showing spines and leaf bases. Scale bar = 2 cm.

Grayum, Hammel, and Jiménez Madrigal: Scientific name for the Tahitian lime 3

Figure 2. Citrus </atifolia. Flowering and fruiting branches, with fruit sliced longitudinally (Hammel & Pérez
24125); inset showing glandular dots (largest ca. 0.3 mm diam.). Scale bar = 5 cm.

Grayum, Hammel, and Jiménez Madrigal: Scientific name for the Tahitian lime 4

latifolia. Fruiting branch on tree (Hammel & Pérez 24125). Scale bar = 5 cm.

Grayum, Hammel, and Jiménez Madrigal: Scientific name for the Tahitian lime

LITERATURE CITED

Mabberley, D.J. 2008. Mabberley’s Plant-Book (ed. 3). Cambridge Univ. Press, New York.

MeNeill, J., F.R. Barrie, H.M. Burdet, V. Demoulin, D.L. Hawksworth, K. Marhold, D.H. Nicolson,
J. Prado, P.C. Silva, JE. Skog, JH. Wiersema & N.J. Turland (eds.). 2006. International
Code of Botanical Nomenclature (Vienna Code). Regnum Veg. 146: 1-568.

Tanaka, T. 1932. Philippine Rutaceae-Aurantioideae (Revisio aurantiacearum VII.). Trans. Nat.
Hist. Soc. Formosa 22(123): 418-433.

Tanaka, T. 1938. A report on the Philippine plant industry. J. Soc. Trop. Agric. 10: 348-353.

Tanaka, T. 1939. A report of the investigation of Philippine Citrus. Stud. Citrol. 9(1, 2): 1-34.

Tanaka, T. 1951. Kwaju bunruigaku [Systematic Pomology]. Kawade Shabo, Tokyo.

Tanaka, Y. 1948. An Iconograph of Japanese Citrus Fruits: A Monographic Study of Species and
Varieties of Citrus Fruits Grown in Japan, Vol. I. Yékendé Co. Ltd., Tokyo.

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