ARTÍCULO

Typification of three names in the genus Galium (Rubiaceae)

PEDRO PABLO FERRER-GALLEGO

Servicio de Vida Silvestre, Centro para la Investigación y la Experimentación Forestal de la Generalitat Valenciana (CIEF), av. Comarques del País Valencià, 114, ES-46930 Quart de Poblet, Valencia, España


ORCID iD. P. P. Ferrer-Gallego: https://orcid.org/0000-0001-7595-9302


Email: flora.cief@gva.es


Editor: A. Susanna


ABSTRACT
Typification of the three names in the genus Galium (Rubiaceae).— The typification of three names in the genus Galium described from the eastern Iberian Peninsula: G. valentinum, G. valentinum var. idubedae, and G. capillare, is discussed. The designation of the nomenclatural types is based on the consultation of original material and the literature cited in the respective protologues. The names are lectotypified using specimens from C (John Lange herbarium), JE, and a Cavanilles’ original illustration published in 1793.
KEY WORDS: Cavanilles; lectotype; nomenclature; taxonomy.

RESUMEN
Tipificación de tres nombres en el género Galium (Rubiaceae).— Se discute la tipificación de tres nombres en el género Galium descritos para el este de la Península Ibérica: G. valentinum, G. valentinum var. idubedae y G. capillare. La designación de los tipos de nomenclaturales se basa en la consulta del material original y la literatura citada en los respectivos protólogos. Los nombres se lectotipifican utilizando especímenes conservados en C (herbario John Lange), JE y una ilustración original de Cavanilles publicada en 1793.
PALABRAS CLAVE: Cavanilles; lectotipo; nomenclatura; taxonomía.

Received 18 November 2020; accepted 22 April 2021; published on line 15 July 2021

Cómo citar este artículo / Citation: Ferrer-Gallego, P. P. 2021. Typification of three names in the genus Galium (Rubiaceae). Collectanea Botanica 40: e007. https://doi.org/10.3989/collectbot.2021.v40.007

Copyright: © 2021 CSIC. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International (CC BY 4.0) License.

CONTENIDOS

ABSTRACT
RESUMEN
INTRODUCTION
MATERIALS AND METHODS
RESULTS AND DISCUSSION
ACKNOWLEDGEMENTS
REFERENCES

INTRODUCTIONTop

Galium L. is one of the largest genera of the Rubiaceae (subfamily Rubioideae), with about 650 species and approximately 780 taxa placed in 16 sections, including perennial and annual herbs that are distributed in temperate and tropical regions of the world, but also in alpine and arctic regions (Willis, 1985Willis, J. C. 1985. A dictionary of the flowering plants and ferns (8th ed.). Cambridge University Press, Cambridge.; Mabberley, 1987Mabberley, D. J. 1987. The plant book. Cambridge University Press, Cambridge.; Ehrendorfer et al., 2005Ehrendorfer, F. & Schönbeck-Temesy, E. 2005. Galium L. In: Ehrendorfer, F., Schönbeck-Temesy, E., Puff, C. & Rechinger, W. (Eds.), Flora Iranica 176. Verlag des Naturhistorischen Museums Wien, Vienna: 161–258.; Tao & Ehrendorfer, 2011Tao, C. & Ehrendorfer, F. 2011. Galium L. In: Wu, Z., Raven, P. H. & Hong, D. (Eds.), Flora of China 19. Science Press, Beijing & Missouri Botanical Garden Press, St. Louis: 104–141.).

Typification should be the starting point of any taxonomic study especially in a difficult genus such as Galium. Several species of Galium are very difficult to identify correctly because the plants present seasonal changes in the morphology of vegetative parts (Ehrendorfer et al., 1994Ehrendorfer, F., Manen, J.-F. & Natali, A. 1994. cpDNA intergene sequences corroborate restriction site data for reconstructing Rubiaceae phylogeny. Plant Systematics and Evolution 190: 195–211. https://doi.org/10.1007/BF00986196, 2014Ehrendorfer, F., Vladimirov, V. & Barfuss, M. H. J. 2014. Paraphyly and polyphyly in the worldwide tribe Rubieae (Rubiaceae): Challenges for generic delimitation. Annals of the Missouri Botanical Garden 100: 79–88. https://doi. org/10.3417/2012088; Soza & Olmstead, 2010Soza, V. L. & Olmstead, R. G. 2010. Molecular systematics of tribe Rubieae (Rubiaceae): Evolution of major clades, development of leaflike whorls, and biogeography. Taxon 59: 75–771. https://doi.org/10.1002/tax.593008).

As a further contribution in our studies to the nomenclature in the genus Galium and Asperula L. (see e.g. Ferrer-Gallego, 2015Ferrer-Gallego, P. P. 2015. Typification of the Linnaean name Asperula cynanchica (Rubiaceae). Phytotaxa 195: 98–100. https://doi.org/10.11646/phytotaxa.195.1.10, 2020Ferrer-Gallego, P. P. 2020. Typification of Linnaean specific names in the genus Galium (Rubiaceae). Taxon 69: 1062–1071. https://doi.org/10.1002/tax.12243; Ferrer-Gallego & Laguna, 2018Ferrer-Gallego, P. P. & Laguna, E. 2018. Typification of two names in the genus Asperula L. (Rubiaceae) Collectanea Botanica 37: e008. https://doi.org/10.3989/collectbot.2018.v37.008; Ferrer-Gallego et al., 2019Ferrer-Gallego, P. P., Roselló, R., Laguna, E. & Peris, J. E. 2019. Typification of two Cavanillesian names, Galium fruticescens (Rubiaceae) and Scorzonera pumila (Compositae). Nemus 9: 181–185.), I here discuss the nomenclatural types of three names: G. capillare Cav., G. valentinum Lange, and G. valentinum var. idubedae Pau ex Debeaux. The purpose of this paper is to contribute to the stability of the nomenclature by the lectotypification of these three names. The combination G. valentinum var. idubedae is currently accepted with species rank as G. idubedae (Pau ex Debeaux) Pau, and the name G. capillare is treated as a synonym of G. setaceum Lam. (see Ehrendorfer et al., 1976Ehrendorfer, F., Krendl, F. & Puff, C. 1976. Galium L. In: Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A. (Eds.), Flora Europaea 4. Cambridge University Press, Cambridge: 14–36.; Ortega Olivencia & Devesa, 2007Ortega Olivencia, A. & Devesa, J. A. 2007. Galium L. In: Devesa, J. A., Gonzalo, R. & Herrero, A. (Eds.), Flora iberica 15. Real Jardín Botánico (CSIC), Madrid: 56–162.).

MATERIALS AND METHODSTop

The names are arranged in alphabetic order, followed by homotypic synonyms (indicated with the symbol ≡) and/or heterotypic synonyms (with the symbol =). Currently accepted names are set in bold italic typeface. Herbarium acronyms follow Thiers (2020Thiers, B. 2020. Index Herbariorum: a global directory of public herbaria and associated staff. New York Botanical Garden’s Virtual Herbarium. Retrieved January 14, 2020, from: http://sweetgum.nybg.org/science/ih ).

RESULTS AND DISCUSSIONTop

Galium capillare

The protologue of Galium capillare includes a complete description followed by a provenance “Habitat in montes S. Michaëlis iuxta Orcellitanam urbem, copiosus vero in colle vulgo Montaña Verde prope oppidum Pego”; a comment “Floret Maio, hicque etiam Teucrium botrys, Anagallis tenella, Cistus laevipes, […]”; an excellent illustration of this plant and its explanation (Cavanilles, 1793Cavanilles, A. J. 1793. Icones et descriptiones plantarum, quae aut sponte in Hispania crescunt, aut in hortis hospitantur, vol. 2. Typographia regia, Madrid.: 73, tab. 191, fig. 1). The drawing included in the protologue illustrates a complete plant, with leaves, flowers, and fruits, including several details of the flowers and fruits (see Fig. 1). Therefore, this illustration can be considered original material of G. capillare.

Figure 1. Lectotype of Galium capillare Cav.; [illustration] “Galium capillare” in Cavanilles (1793Cavanilles, A. J. 1793. Icones et descriptiones plantarum, quae aut sponte in Hispania crescunt, aut in hortis hospitantur, vol. 2. Typographia regia, Madrid.: tab. 191, fig. 1).

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Garilleti (1993Garilleti, R. 1993. Herbarium Cavanillesianum, seu, Enumeratio plantarum exsiccatarum aliquo modo ad novitates Cavanillesianas pertinentium, quae in Horti Regii Matritensis atque Londinensis Sociatatis Linnaeanae herbariis asservantur. Fontqueria 38: 6–248.: 206) indicated that he did not find original material in the Cavanilles Herbarium at MA and LINN. In this sense, I have not been able to locate any Cavanilles’ original material of G. capillare in these two herbaria. However, I have found two relevant specimens of this species at MPU. The specimen with barcode MPU024396 bears a complete plant, with leaves and fruits, and a label, partially handwritten by Cavanilles: “Galium capillare Cavanilles / Setaceum Vahl / dedit Cavanilles [perhaps handwritten by Cavanilles]” (image available at https://herbier.umontpellier.fr/zoomify/zoomify.php?fichier=MPU024396). The specimen with barcode MPU024395 bears a stem, with leaves and fruits, and a label: “Galium capillare Cav.! Icon. / Dedit Cavanilles” (image available at https://herbier.umontpellier.fr/zoomify/zoomify.php?fichier=MPU024395).

Unfortunately, these two specimens at MPU lack relevant information such as provenance and date of collection. Therefore, although they may be original material, it is not possible to accredit this statement, so I do not recommend their choice as a lectotype.

In conclusion, the excellent illustration “Galium capillare” published by Cavanilles (1793Cavanilles, A. J. 1793. Icones et descriptiones plantarum, quae aut sponte in Hispania crescunt, aut in hortis hospitantur, vol. 2. Typographia regia, Madrid.: tab. 191, fig. 1) is designated as the lectotype of the name Galium capillare. This illustration matches the traditional concept of the name G. capillare, which is currently treated as a heterotypic synonym of G. setaceum Lam. (see Ortega Olivencia & Devesa, 2007Ortega Olivencia, A. & Devesa, J. A. 2007. Galium L. In: Devesa, J. A., Gonzalo, R. & Herrero, A. (Eds.), Flora iberica 15. Real Jardín Botánico (CSIC), Madrid: 56–162.).

Galium capillare Cav., Icon. 2: 73, tab. 191, fig. 1. 1793

Ind. loc.: “Habitat in montes S. Michaëlis iuxta Orcellitanam urbem, copiosus vero in colle vulgo Montaña Verde prope oppidum Pego”

Lectotype (designated here): [illustration] “Galium capillare” in Cavanilles (1793Cavanilles, A. J. 1793. Icones et descriptiones plantarum, quae aut sponte in Hispania crescunt, aut in hortis hospitantur, vol. 2. Typographia regia, Madrid.: tab. 191, fig. 1) (Fig. 1).

= G. setaceum Lam. in Lam. & Poir., Encycl. 2: 584. 1788

Galium valentinum

Lange (1882Lange, J. 1882. Diagnoses plantarum peninsulae ibericae novarum, a variis collectoribus recentiori tempore lectarum autore. Videnskabelige Meddelelser fra den Naturhistoriske Forening i Kjöbenhavn 1881: 93–105. : 95) described Galium valentinum providing a complete description in Latin, followed by a diagnosis, the geographical locality, and a particular gathering “In declivibus montis Mariolae supra Alcoy regn. Valent. 15 Maj 1878 legit cl. Prof. Hegelmaier”.

In the personal herbarium of John Lange at C there is an original sheet related to this name that belong to the gathering cited in the protologue. This syntype, with barcode C10023594, bears several plants, with leaves, flowers, and fruits, and has a label annotated as “Herb. Joh. Lange / Galium valentinum Lge / Hispania. Prov. Alicante / In declivibus montis Mariola supra / Alcoy / F. Hegelmaier 1878. 15 Mai / corollae luteae” (Fig. 2).

Figure 2. Lectotype of Galium valentinum Lange; C10023594. Image courtesy of the herbarium C, reproduced with permission.

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I have not been able to locate any further original material in any consulted herbaria, and possibly the specimen at C is the only specimen of the gathering and the only original material that was used by Lange in the description of this name. However, as I cannot exclude that there are more than one specimen of this taxon, I consider the specimen as the lectotype of the name Galium valentinum, admitting that the specimen might well be the holotype (see McNeill, 2014McNeill, J. 2014. Holotype specimens and type citations: General issues. Taxon 63: 1112–1113. https://doi.org/10.12705/635.7). This specimen matches the traditional concept and the current use of the name, showing some diagnostic features (e.g. stems slender, retrorsely aculeolate; leaves with upper surface and margin antrorsely scabridulous; hyaline apex short; inflorescence many-flowered, ovoid; pedicels divaricate; corolla 1.7–2 mm in diameter, yellowish, fruit ca. 1 mm, shining, papillose; cf. Ehrendorfer et al., 1976Ehrendorfer, F., Krendl, F. & Puff, C. 1976. Galium L. In: Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A. (Eds.), Flora Europaea 4. Cambridge University Press, Cambridge: 14–36.; Ortega Olivencia & Devesa, 2007Ortega Olivencia, A. & Devesa, J. A. 2007. Galium L. In: Devesa, J. A., Gonzalo, R. & Herrero, A. (Eds.), Flora iberica 15. Real Jardín Botánico (CSIC), Madrid: 56–162.).

Galium valentinum Lange in Vidensk. Meddel. Dansk Naturh. Forenh. Kjobenh. 1881: 95. 1882

Ind. loc.: “In declivibus montis Mariolae supra Alcoy regn. Valent.”

Lectotype (designated here): SPAIN, Alicante, “In declivibus montis Mariolae supra Alcoy”, 15 May 1878, F. Hegelmaier s.n., C (barcode C10023594 [photo!]; Fig. 2).

Galium valentinum var. idubedae

In the protologue of Galium valentinum var. idubedae (Debeaux, 1897Debeaux, M. O. 1897. Plantes rares ou nouvelles de la province d’Aragon (Espagne). Provenant des récoltes de M. Reverchon en 1895. Troisième fascicule. Revue de Botanique, Bulletin Mensuel 15: 130–180.: 153–154) is indicated “Var. β Idubedae C. Pau in Herb. ined. (1895); G. valentinum E. Rev. Plant Téruel exs. nº 664 (1891 et 1895); Willk. Suppl. fl. hispan. p. p.”, followed by a brief description in French “Cette variété a été rapportée à tort au type G. valentinum par quelques auteurs. Elle s’en sépare par son port plus robuste, ses tiges plus élevées (30–40 centim.), ses feuilles 2–3 fois plus allongéees, linéaires, étroites, arquées, mucronulées au sommet, brillantes à la surface, par ses pédoncules fructifères plus longs, pauciflores, à rameaux étalés dressés”. The provenance was also reported: “La Sierra d’Espadan (Idubeda des anciens), dans les prés et les maquis, sur le calcaire (E. Rev., C. Pau); Pico de Peñagolosa, Sierra de Javalambre (E. Rev. 1891)”.

Debeaux explicitly cited in the protologue several gatherings, with detailed localities, collection dates, and authors “G. valentinum E. Rev. Plant Téruel exs. nº 664 (1891 et 1895)”, “La Sierra d’Espadan [...] (E. Rev., C. Pau)”, and “Pico de Peñagolosa, Sierra de Javalambre (E. Rev. 1891)”, and also a particular herbarium material “C. Pau in Herb. ined. (1895)”.

In this sense, Pau (1898Pau, C. 1898. Notas sobre algunas plantas españolas críticas ó nuevas. Actas de la Sociedad Española de Historia Natural 1898: 84–90. : 85) indicated “Fundado en estas consideraciones, he comunicado à mis corresponsales las muestras de Espadán, que recogí en los alcornocales, como G. Idubedae (Reverch. exs. 1891, n. 14)” [Based on these considerations, I have communicated to my correspondents the specimens of Espadán, which I collected in the cork oaks, as G. Idubedae (Reverch. exs. 1891, n. 14)].

I have found some relevant specimens of this species at several herbaria. In the Pau herbarium at MA there are two specimens relevant for typification, MA00431617 and MA00117705. The specimen MA00431617 was collected by Pau in Peñagolosa in June 1891. The specimen MA00117705 was collected by Pau in Sierra de Espadán in June 1875 and matchs with the specimen indicated by Debeaux in the protologue “La Sierra d’Espadan [...] (E. Rev., C. Pau)”. These two specimens are undoubtedly syntypes of G. valentinum var. idubedae.

In the herbarium JE there is a specimen, JE00009734, that can be treated as original material of the name. The sheet bears a complete plant, with leaves, flowers and fruits, and a printed label from the Reverchon exsiccatum [G. valentinum E. Rev. Plant Téruel exs. nº 664 (1891 et 1895)] cited in the protologue by Debeaux. This printed label is annotated as “Elisée Reverchon – Plantes d’Espagne – 1891 / Province de Valence / Nº 664 / Galium Valentinum Lge. / Willkomm. / Sierra de Espadan, mâquis herbeux, sur le calcaire triasique. / 1.800 mètres / Juillet” (Fig. 3). In addition, two duplicate specimens of this material are preserved at WU (barcode WU0033772) and G (barcode G00436208 [two sheets]). These sheets bear well-developed plants and also the same printed label that the sheet JE00009734. These three specimens (at JE, WU, and G) are therefore syntypes.

Figure 3. Lectotype of Galium valentinum var. idubedae Pau ex Debeaux; JE00009734. Image courtesy of the herbarium JE, reproduced with permission.

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In conclusion, in all cases the specimens match with the traditional concept and the current use of the name, showing important diagnostic features (e.g. stems with middle internodes shorter than or up to twice as long as the leaves; leaves acicular, 13–20 times as long as wide; margin more or less thickened, flat; midrib somewhat thickened, hyaline apex; inflorescence more or less corymbose; corolla 2–2.5(–3.5) mm in diameter; fruit 1–1.5 mm, weakly papillose; cf. Ehrendorfer et al., 1976Ehrendorfer, F., Krendl, F. & Puff, C. 1976. Galium L. In: Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A. (Eds.), Flora Europaea 4. Cambridge University Press, Cambridge: 14–36.; Ortega Olivencia & Devesa, 2007Ortega Olivencia, A. & Devesa, J. A. 2007. Galium L. In: Devesa, J. A., Gonzalo, R. & Herrero, A. (Eds.), Flora iberica 15. Real Jardín Botánico (CSIC), Madrid: 56–162.). I designate as the lectotype of the name Galium valentinum var. idubedae the specimen JE barcode JE00009734 because it is a complete specimen that also has two duplicates.

Galium valentinum var. idubedae Pau ex Debeaux in Rev. Bot. Bull. Mens. 15: 153. 1897

G. idubedae (Pau ex Debeaux) Pau in Actas Soc. Esp. Hist. Nat. 27: 85. 1898

G. pusillum subsp. idubedae (Pau ex Debeaux) Vigo in Arxius Secc. Ci. Inst. Estud. Catalans 37: 91. 1968

Ind. loc.: “La Sierra d’Espadán (Idubeda des anciens), dans les prés et les maquis, sur le calcaire (E. Rev., C. Pau); Pico de Péñagolosa, Sierra de Javalambre (E. Rev. 1891)”

Lectotype (designated here): [SPAIN. Castellón] Sierra de Espadán, 1800 m, July 1891, E. Reverchon 664, JE (JE00009734 [photo!]) (Fig. 3). Isolectotypes: WU0033772 [photo!], G00436208 [photo!].

ACKNOWLEDGEMENTSTop

Thanks to Olof Ryding (Herbarium C) and Eva García (Herbarium MA) for the images of the herbarium sheets. Thanks also to Ana Mira (Jardí Botànic de la Universitat de València, Spain) for her help in the study of several references cited in the work.

REFERENCESTop

1. Cavanilles, A. J. 1793. Icones et descriptiones plantarum, quae aut sponte in Hispania crescunt, aut in hortis hospitantur, vol. 2. Typographia regia, Madrid.
2. Debeaux, M. O. 1897. Plantes rares ou nouvelles de la province d’Aragon (Espagne). Provenant des récoltes de M. Reverchon en 1895. Troisième fascicule. Revue de Botanique, Bulletin Mensuel 15: 130–180.
3. Ehrendorfer, F., Krendl, F. & Puff, C. 1976. Galium L. In: Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A. (Eds.), Flora Europaea 4. Cambridge University Press, Cambridge: 14–36.
4. Ehrendorfer, F., Manen, J.-F. & Natali, A. 1994. cpDNA intergene sequences corroborate restriction site data for reconstructing Rubiaceae phylogeny. Plant Systematics and Evolution 190: 195–211. https://doi.org/10.1007/BF00986196
5. Ehrendorfer, F. & Schönbeck-Temesy, E. 2005. Galium L. In: Ehrendorfer, F., Schönbeck-Temesy, E., Puff, C. & Rechinger, W. (Eds.), Flora Iranica 176. Verlag des Naturhistorischen Museums Wien, Vienna: 161–258.
6. Ehrendorfer, F., Vladimirov, V. & Barfuss, M. H. J. 2014. Paraphyly and polyphyly in the worldwide tribe Rubieae (Rubiaceae): Challenges for generic delimitation. Annals of the Missouri Botanical Garden 100: 79–88. https://doi.org/10.3417/2012088
7. Ferrer-Gallego, P. P. 2015. Typification of the Linnaean name Asperula cynanchica (Rubiaceae). Phytotaxa 195: 98–100. https://doi.org/10.11646/phytotaxa.195.1.10
8. Ferrer-Gallego, P. P. 2020. Typification of Linnaean specific names in the genus Galium (Rubiaceae). Taxon 69: 1062–1071. https://doi.org/10.1002/tax.12243
9. Ferrer-Gallego, P. P. & Laguna, E. 2018. Typification of two names in the genus Asperula L. (Rubiaceae) Collectanea Botanica 37: e008. https://doi.org/10.3989/collectbot.2018.v37.008
10. Ferrer-Gallego, P. P., Roselló, R., Laguna, E. & Peris, J. E. 2019. Typification of two Cavanillesian names, Galium fruticescens (Rubiaceae) and Scorzonera pumila (Compositae). Nemus 9: 181–185.
11. Garilleti, R. 1993. Herbarium Cavanillesianum, seu, Enumeratio plantarum exsiccatarum aliquo modo ad novitates Cavanillesianas pertinentium, quae in Horti Regii Matritensis atque Londinensis Sociatatis Linnaeanae herbariis asservantur. Fontqueria 38: 6–248.
12. Lange, J. 1882. Diagnoses plantarum peninsulae ibericae novarum, a variis collectoribus recentiori tempore lectarum autore. Videnskabelige Meddelelser fra den Naturhistoriske Forening i Kjöbenhavn 1881: 93–105.
13. Mabberley, D. J. 1987. The plant book. Cambridge University Press, Cambridge.
14. McNeill, J. 2014. Holotype specimens and type citations: General issues. Taxon 63: 1112–1113. https://doi.org/10.12705/635.7
15. Ortega Olivencia, A. & Devesa, J. A. 2007. Galium L. In: Devesa, J. A., Gonzalo, R. & Herrero, A. (Eds.), Flora iberica 15. Real Jardín Botánico (CSIC), Madrid: 56–162.
16. Pau, C. 1898. Notas sobre algunas plantas españolas críticas ó nuevas. Actas de la Sociedad Española de Historia Natural 1898: 84–90.
17. Soza, V. L. & Olmstead, R. G. 2010. Molecular systematics of tribe Rubieae (Rubiaceae): Evolution of major clades, development of leaflike whorls, and biogeography. Taxon 59: 75–771. https://doi.org/10.1002/tax.593008
18. Tao, C. & Ehrendorfer, F. 2011. Galium L. In: Wu, Z., Raven, P. H. & Hong, D. (Eds.), Flora of China 19. Science Press, Beijing & Missouri Botanical Garden Press, St. Louis: 104–141.
19. Thiers, B. 2020. Index Herbariorum: a global directory of public herbaria and associated staff. New York Botanical Garden’s Virtual Herbarium. Retrieved January 14, 2020, from: http://sweetgum.nybg.org/science/ih
20. Willis, J. C. 1985. A dictionary of the flowering plants and ferns (8th ed.). Cambridge University Press, Cambridge.