On the taxonomy and typification of Morinda lucida Benth. (Rubiaceae)Taxonomy and typification of Morinda lucida Benth. (Rubiaceae)Gopika GOPANhttps://ror.org/025y1an670000-0003-1185-6149V. P. THOMAShttps://ror.org/025y1an670000-0003-3673-4535Binoy T. THOMAShttps://ror.org/025y1an670000-0002-3517-22462025-05-06T12:04:00Muséum national d'Histoire naturelle19-2510/02/202547 (3)10/02/202510.5252/adansonia2025v47a3

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color:black;RubiaceaeMorindalectotypification.RubiaceaeMorindalectotypification.RévisionOn the taxonomy and typification of Morinda lucida Benth. (Rubiaceae)Gopika GOPANCATH Herbarium, Postgraduate and Research Department of Botany, Catholicate College, Pathanamthitta, Kerala, 689 645 (India) V. P. THOMASCATH Herbarium, Postgraduate and Research Department of Botany, Catholicate College, Pathanamthitta, Kerala, 689 645 (India) Binoy T. THOMASCATH Herbarium, Postgraduate and Research Department of Botany, Catholicate College, Pathanamthitta, Kerala, 689 645 (India)

ABSTRACT. Morinda lucida Benth. (Rubiaceae) an important medicinal plant used by natives of Africa is typified here. The specimen housed at K bearing barcode number K000379504 is designated here as lectotype of M. lucida and digital image of lectotype is presented here. A detailed description, illustration and photographs are also provided for the easy identification of species.

KEYWORDS: Rubiaceae, Morinda, lectotypification.

RÉSUMÉ. Morinda lucida Benth. (Rubiaceae), une importante plante médicinale utilisée par les natifs d’Afrique, est typifiée ici. Le spécimen de l’herbier K portant le numéro de code barres K000379504 est désigné ici comme lectotype de M. lucida et est illustré. Une description détaillée, une illustration et des photographies sont également fournies pour faciliter l’identification de l’espèce.

MOTS CLÉS: Rubiaceae, Morinda, lectotypification.

INTRODUCTION

The genus Morinda L. is a prominent genus within the Rubiaceae, and comprises 39 accepted species with distribution in tropical and subtropical regions (POWO 2024). The genus is characterized by its predominantly shrubby and arboreal habit, possession of petiolate or subsessile leaves, chartaceous to coriaceous lamina, terminal or axillary leaf opposed head of flowers, bilocular ovary and syncarpous fruit (Kesonbua & Chantaranothai 2013). Morinda ‌lucida ‌Benth. is an African native, specifically found in regions ranging from Senegal to Sudan and extending southwards to Angola and Zambia, as well as Nigeria (Vijayakumar et al. 2017). Recently, Vijayakumar et al. (2017) reported the occurrence of M. ‌lucida ‌Benth. from Nagapattinam district of Tamil Nadu. Unfortunately, field exploration and herbarium visits did not lead us to locate specimens from India.

Morinda ‌lucida is a nutraceutical plant, exhibits a diverse array of pharmacological activities. Its historical usage by rural communities primarily stems from its perceived medicinal properties (Adeyemi et al. 2014). Archana et al. (2023) misidentified M. ‌lucida in their studies of exploring antitumour potential against melanoma cancer. Furthermore, within the comprehensive examination encompassing ethnomedicinal applications, phytochemistry, pharmacological properties, clinical implications, and toxicological assessments of eleven Morinda species indigenous to India, it has come to light that there exists a notable occurrence of misidentification pertaining to M. ‌lucida ‌(Singh & Sharma 2019). Misidentification of medicinal plants poses significant barriers to their marketing and consumption. Consequently, it is imperative to ensure accurate identification and authentication of the respective species. The name M. ‌lucida has not yet been typified properly from a nomenclatural aspect. Therefore, lectotype (K000379504!) is selected from the original material used by Bentham and designated.

MATERIAL AND METHODS

Taxonomic studies were carried out based specimens housed at various herbaria in India and on the open access foreign digital herbaria viz. BM, BR, CATH, COI, DR, FHI, GC, HNBU, K, NMNH and YA. Live materials of M. ‌lucida cultivated in the Lalbagh Botanical Garden, Bangalore were also used for the preparation of detailed description and illustration of taxa. After a critical evaluation of type material and protologue, lectotype is designated for M. ‌lucida in accordance with ICN (Turland et al. 2018). Distribution map was prepared using Simple Mappr, based on data accessed from IUCN Red list (IUCN SSC & BGCI 2020), GBIF (GBIF 2024) and wild collections deposited at various digital herbaria.

Abbreviations
Collection acronyms

BM Herbarium, Natural History Museum;

BR Herbarium, Meise Botanical Garden;

CATH Herbarium, Catholicate College, Pathanamthitta;

COI Herbarium, University of Coimbra;

DR Herbarium, Technische Universität Dresden;

FHI Herbarium, Forestry Research Institute of Nigeria;

GC Herbarium, University of Ghana

HNBU Herbarium, Institut de l’Environnement et de Recherche Agricola (INERA);

K Herbarium, Royal Botanic Gardens, Kew;

NMNH National Museum of Natural History, New Delhi;

YA National Herbarium of Cameroon.

TAXONOMIC TREATMENT‌ Rubiaceae ‌Juss.‌ Morinda L.
Morinda ‌lucida ‌Benth.d1e334d1-e334-4d1e-b34d-1e334d1e334

(Figs 1; 2; 3)

Niger Flora, London 849: 406 (Bentham in Hooker 1849).

Type material

Equatorial Guinea•Fernando Po leg.; De Vogel 77; lectotype: K[K000379504!], here designated.

Phenology

Flowering and fruiting is from July-December.

Global distribution

Angola, Benin, Cabinda, Cameroon, Central African Republic, Congo, Gabon, Ghana, Guinea, Guinea-Bissau, Gulf of Guinea Is., Ivory Coast, Liberia, Nigeria, Senegal, Sierra Leone, Sudan, Tanzania, Togo, Uganda, Zaïre (POWO 2024) (Fig. 4).

IUCN Status

M. lucida has wide distribution and the species is not currently affected by any major threats and assessed under the category Least concern (IUCN SSC & BGCI 2020).

Specimen examined

India • Karnataka, Bengaluru, Lalbagh Botanical Garden; 900 m alt.; 12°56’20.4”N, 77°35’04.9”E; 20.VI.2023; Gopika Gopan 21050; CATH[CATH21050].

Ghana • Greater Accra Region, Ada; 1.I.1784; Isert s.n.; C[C10004191]•Achimota; III.1931; Irvine 1602; GC[GC000007778]•Dixcove; 31.III.1954; Morton A478; GC[GC000007779].

Equatorial Guinea • Fernando Po leg.; Vogel 77; K[K000379504].

Angola • Cuanza Norte;VI.1935; John 10305; COI[COI00067774]•Cabinda, Belize P. O. Maiombe; 31.XII.1918; John 10170; COI[COI00067776]•Cuanza Norte, Gossweiler; VI.1935; John 10305; COI[COI00067775] • Uige, Quimbele, Kibokolo; 20.III.2018; Jendras leg.; DR[DR051641, DR051642].

Côte d’Ivoire • Abidjan; 21.IV.1967; Bonzi 908; HNBU[HNBU02209].

Liberia • Iboke, Cavalla River drainage; 24.V.1948; Mayer 133; NMNH[NMNH00819075].

Togo • Lome-Palime; 2.IX.1971; Breteler 7125; NMNH[NMNH02692471].

Cameroon • South-west province; 20.VIII.1983; Thomas 2484; YA[YA0053750]•Bates 1185; BM[BM014128248)]•Municipio de Kembele; 20.II.2015; Ditsch BD777; DR[DR067666].

Burkina Faso • Sud-Ouest; 10.VII.1986; Etuge et al. 206; NMNH[NMNH02692470].

Congo • Province Orientale, Ango, Mombele Camp Chefferie; 1938; Gilbert 1654; NMNH[NMNH02692472]•Province Orientale, Territory Isangi, Jangambi; Gilbert 1147; NMNH[NMNH02692473)]•Louis 1144; BR[BR0000006860677].

Gabon • III.1904; Klaine 3466; NMNH[NMNH02692475].

Nigeria • 27.IV.1977; Ibhanesebhor et al. GJ174; FHI[FHI0089510-0].

Description

Evergreen trees. Bark glabrous, rough, pale brown. Branchesquadrangular in younger and terete to older branches. Leaves opposite-decussate, elliptical, petiolate, glossy; petiole smooth, 0.8-1.4 × 0.15-0.2 cm, slightly pubescent towards base; lamina elliptic, glossy, 7.0-13 × 3.5-5.8 cm, base attenuate, margin entire and wavy, apex acute to acuminate; lateral veins 5-7 pairs, raised abaxially; domatium present on the axils of lateral veins in abaxial surface. Stipules entire, green, glabrous, 0.2-0.7 × 0.3-0.6 cm, forming sheath enclosing basal parts of the internode, not persistent, colleters on adaxial base. Inflorescence terminal and axillary heads; ovaries connate into pedunculate capitula, each capitulum composes of 5-7 flowers fused by its ovaries. Flowers tubular, 2.1-2.5 cm long, white, fragrant, sessile, glabrous. Peduncle 3-4 per node, 1.8-4.5 ×0.15 cm, green, glossy, slightly hairy, one larger and smaller knob-like gland between peduncle and stem. Calyx truncate, 0.25-0.35 cm long, adnate to the ovary, green and glabrous. Corolla valvate, white; tube greenish-white, 1.6-2 cm long, glossy, glabrous outside and slightly hairy inside; throat glabrous; lobes 5, salver shaped, 0.5–0.6 × 0.25-0.3 cm, entire margin, apex acute and hooded at tip, glossy. Stamens 5, epipetalous, introrse; filaments white, 1.5-2 cm long, glabrous; anther 2-celled, 0.4-0.5 × 0.05-0.1 cm, dorsifixed, whitish yellow, glabrous, dehiscent longitudinally; pollen numerous. Ovary 0.2-0.3 cm in diameter, 2 locules, 1 ovule per locule; style greenish, 0.7-1.2 cm long, smooth, glossy; stigma greenish white, inserted in corolla tube, bifid. Infructescence syncarpous, 1-1.5 × 1.2-1.5 cm, greenish color turning blackish brown on ripening, smooth, calyx persistent and glabrous. Seeds 4-5, triangular, 0.6-0.75 × 0.4-0.5 cm, blackish brown, not winged, wrinkled, numerous.

Typification remarks

George Bentham described M. ‌lucida in Hooker’s Niger Flora (Bentham inHooker 1849). In the protologue, Bentham gave a brief diagnosis based on the collections made by De Vogel from two regions in Equatorial Guinea: Quorra & Fernando Po (Bioko). While searching for the original materials, the specimen from Quorra has not been traced from any herbaria and material collected by De Vogel from Bioko is located at herbarium of Royal Botanic Gardens, Kew (barcode number: K000379504). Daniel Oliver discussed about two Morinda species in the Flora of Tropical Africa (Oliver 1877: 191), Morinda ‌citrifolia L. and Morinda ‌longiflora ‌G.Don. He mentioned M. ‌lucida as a variety of M. ‌citrifolia and labelled the specimen of De Vogel as M. ‌citrifolia L.

Description and illustrations of African Morinda

M. ‌longiflora, M. ‌confusa, M. ‌lucida and M. ‌geminata has been described and illustrated in Bulletin of Miscellaneous Information (Hutchinson 1916). Hutchinson & Dalziel (1963) identified De Vogel’s material as M. ‌lucida and published in the Flora of West Tropical Africa. Davis & Figueiredo (2007) published a detailed checklist of the Rubiaceae on the islands of Bioko and Annobon based on herbarium collections from K and BMNH. In this, De Vogel material of M. ‌lucida was described as a syntype and Barter 2039 (K) as a representative specimen. We consider the most appropriate choice of lectotype to be the De Vogel specimen in K with barcode K000379504. This specimen clearly shows the main morphological features identifying it as M. ‌lucida, i.e. oval shaped leaf with brief petiole, 1-3 peduncles per node and globose capitulum.

Acknowledgements

The authors are thankful to the authorities of Royal Botanic Gardens, Kew for providing access to the herbarium specimens and providing permission to publish digital image of type. We are grateful to Dr P. E. Rajasekharan, former Principal Scientist, IIHR, Bengaluru and authorities of Lalbagh Botanical Garden for supporting this research work. We are thankful to authorities of BM, BR, COI, DR, FHI, GC, HNBU, K, NMNH and YA for providing online herbaria resources. We are thankful to Ranjith Layola, NBRI, for the guidance rendered for the preparation of distribution map. Two anonymous referees are also thanked for their remarks on a previous version of the manuscript.

Fig. 1. — Morinda ‌lucida ‌Benth.: A, habit; B, twig; C, flowers; D, gland; E, domatium; F, single flower; G, corolla tube opened; H, corolla throat inside; I, style and stigma; J, fruit; K, seed. Scale bars: A, C, F, not to scale; B, 2 cm; D, K, 1 mm; E, 0.5 mm; G, 1 cm; H-J, 2 mm.
Fig. 2. — Morinda ‌lucida ‌Benth.: A, flowering twig; B, inflorescence; C, flower; D, flower split open; E, corolla lobes; F, calyx; G, colleters in stipule; H, domatia in axils of secondary veins; I, stamen; J, style and stigma; K, c.s. of ovary; L, fruit; M, seed. Scale bars: A, B, H, 1 cm; C, D, I, 0.2 cm; E-G, J, K, M, 0.1 cm; L, 0.3 cm.
Fig. 3. — Lectotype of Morinda lucida Benth., Vogel 77 (K000379504) © The Board of Trustees of the Royal Botanic Gardens, Kew.
Fig. 4. — Distribution map of M. ‌lucida ‌Benth.
REFERENCESAdeyemi T. O. A., Ogborur O., Idowu R. O., Owoeye E. A. & Isese M. O. 2014. — Phytochemical screening and health potentials of Morinda lucida Benth. International Journal of Innovation and Scientific Research 11 (2): 515-551.Adeyemi ‌T. O. A., Ogborur ‌O., Idowu ‌R. O., Owoeye ‌E. A. & Isese ‌M. O.2014Phytochemical screening and health potentials of Morinda lucida BenthInternational Journal of Innovation and Scientific Research112515551Archana D. B., Chadha M., Sanghavi S. J., Mazha M., Muztaba M., Saroj B. K. & Sharma K. 2023. — Morinda lucida extract composition for treatment of melanoma cancer and anti-malarial activity and its preparation. European Chemical Bulletin 12: 2962-2972. https://doi.org/10.31838/ecb/2023.12.sa1.184Archana ‌D. B., Chadha ‌M., Sanghavi ‌S. J., Mazha ‌M., Muztaba ‌M., Saroj ‌B. K. & Sharma ‌K.2023Morinda lucida extract composition for treatment of melanoma cancer and anti-malarial activity and its preparationEuropean Chemical Bulletin1229622972https://doi.org/10.31838/ecb/2023.12.sa1.184Davis A. P. & Figueiredo E. 2007. — A checklist of the Rubiaceae on the islands of Bioko and Annobon (Equatorial Guinea, Gulf of Guinea). Systematics and Biodiversity 5 (2): 159-186. https://doi.org/10.1017/S1477200006002143Davis ‌A. P. & Figueiredo ‌E.2007A checklist of the Rubiaceae on the islands of Bioko and Annobon (Equatorial Guinea, Gulf of Guinea)Systematics and Biodiversity52159186https://doi.org/10.1017/S1477200006002143GBIF 2024. — Global Biodiversity Information Facility. https://www.gbif.org/search?q=Morinda%20lucida (accessed 5 October 2024).GBIF2024Global Biodiversity Information Facilityhttps://www.gbif.org/search?q=Morinda%20lucidaHooker W. J. 1849. — Niger Flora: Or, an Enumeration of the Plants of Western Tropical Africa. Baillière, London, 406 p. https://doi.org/10.5962/bhl.title.594Hooker ‌W. J.1849Niger FloraOr, an Enumeration of the Plants of Western Tropical Africa.Baillière, Londonhttps://doi.org/10.5962/bhl.title.594Hutchinson J. 1916. — African Morinda, in Bulletin of Miscellaneous Information. Royal Botanic Garden, Kew, London: 8-16. https://www.biodiversitylibrary.org/page/11628015Hutchinson ‌J.1916African Morinda, in Bulletin of Miscellaneous InformationRoyal Botanic Garden, Kew, London816https://www.biodiversitylibrary.org/page/11628015Hutchison J. & Dalziel J. M. 1963. — Flora of West Tropical Africa. Crown Agents for Overseas Government and Administration, London: 104-223. https://archive.org/details/FloraOfWestTropi00hutcHutchison ‌J. & Dalziel ‌J. M.1963Flora of West Tropical AfricaCrown Agents for Overseas Government and Administration, London104223https://archive.org/details/FloraOfWestTropi00hutcIUCN SSC Global tree specialist group & BGCI 2020. — M. lucida. The IUCN Red List of Threatened Species. https://doi.org/10.2305/IUCN.UK.2020-3.RLTS.T156109487A156109489.en (accessed on 7 October 2024).IUCN SSC Globaltree specialist group & BGCI2020M. lucida. The IUCNhttps://doi.org/10.2305/IUCN.UK.2020-3.RLTS.T156109487A156109489.enKesonbua W. & Chantaranothai P. 2013. —The genus Morinda (Rubiaceae) in Thailand. Science Asia 39: 331-339. https://doi.org/10.2306/scienceasia1513-1874.2013.39.331Kesonbua ‌W. & Chantaranothai ‌P.2013The genus Morinda (Rubiaceae) in ThailandScience Asia39331339https://doi.org/10.2306/scienceasia1513-1874.2013.39.331Linnaeus C. 1753. — Species plantarum. Laurentii Salvii, Holmiae, Stockholm, 176 p. https://doi.org/10.5962/bhl.title.37656Linnaeus ‌C.1753Species plantarumLaurentii Salvii, Holmiae, Stockholmhttps://doi.org/10.5962/bhl.title.37656Oliver D. 1877. — Flora of Tropical Africa. L. Reeve & Co., London, 191 p. https://doi.org/10.5962/bhl.title.42Oliver ‌D.1877Flora of Tropical Africa. L. Reeve & CoLondonhttps://doi.org/10.5962/bhl.title.42POWO 2024. —Plants of the World Online. The Royal Botanical Gardens, Kew. https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names: 4941-1 (accessed 12 July 2024).POWO2024Plants of the World OnlineThe Royal Botanical Gardens, Kewhttps://powo.science.kew.org/taxon/urn:lsid:ipni.org:names: 4941-1Singh B. & Sharma A. R. 2019. — Indian Morinda species: a review. Phytotherapy Research 34: 924-1007. https://doi.org/10.1002/ptr.6579Singh ‌B. & Sharma ‌A. R.2019Indian Morinda species: a reviewPhytotherapy Research349241007https://doi.org/10.1002/ptr.6579Turland N. J., Wiersema J. H., Barrie F. R., Greuter W., Hawksworth D. L., Herendeen P. S., Knapp S., Kusber W.-H., Li D.-Z., Marhold K., May T. W., McNeill J., Monro A. M., Prado J., Price M. J. & Smith G. F. (eds) 2018. — International Code of Nomenclature for algae, fungi, and plants (Shenzhen Code) adopted by the Nineteenth International Botanical Congress, Shenzhen, China, July 2017. Regnum Vegetabile 159. Glashütten: Koeltz Botanical Books. https://doi.org/10.12705/Code.2018Turland ‌N. J., Wiersema ‌J. H., Barrie ‌F. R., Greuter ‌W., Hawksworth ‌D. L., Herendeen ‌P. S., Knapp ‌S., Kusber ‌W.-H., Li ‌D.-Z., Marhold ‌K., May ‌T. W., McNeill ‌J., Monro ‌A. M., Prado ‌J., Price ‌M. J. & Smith ‌G. F.2018International Code of Nomenclature for algae, fungi, and plants (Shenzhen Code) adopted by the Nineteenth International Botanical Congress, Shenzhen, China, July 2017Regnum Vegetabile159https://doi.org/10.12705/Code.2018Vijayakumar D., Chinnasamy P.& Ariyan S. 2017. — Morinda lucida Benth. S (Rubiaceae) – new record from India. Jordan Journal of Biological Science 10: 37-38.Vijayakumar ‌D., Chinnasamy ‌P.& Ariyan ‌S.2017Morinda lucida Benth. S (Rubiaceae) – new record from IndiaJordan Journal of Biological Science103738