Skip to main content

Takenoshin Nakai swallow-wort (Vincetoxicum nakaianum) replaces V. magnificum and C. magnificum

Takenoshin Nakai swallow-wort (Vincetoxicum nakaianum) replaces V. magnificum and C. magnificum

NEWS - Researchers reported an erect herbaceous species distributed in the eastern part of Honshu Island, Vincetoxicum magnificum (Nakai) Kitag. based on Cynanchum magnificum Nakai, nomen nudum. Therefore, they named this species Takenoshin Nakai swallow-wort (Vincetoxicum nakaianum K.Mochizuki & Ohi-Toma).

Vincetoxicum Wolf (Asclepiadeae) is the third largest genus in the Asclepiadoideae consisting of about 260 species geographically extending from tropical Africa, Asia and Oceania to temperate regions of Eurasia.

A total of 23 species are known from Japan, including 16 endemic species. Molecular phylogeny divides Japanese Vincetoxicum into four groups: the “Far Eastern” clade consisting of 11 endemic species and 4 more widespread species, 1 sister species to the “Far Eastern” clade, the “subtropical” clade consisting of 2 species and the “Vincetoxicum s. str.” clade consisting of 5 species.

V. magnificum (Nakai) Kitag. (Japanese: tachi-gashiwa) is closely related to V. macrophyllum Siebold. & Zucc. (Japanese: tsukushi-gashiwa) and V. macrophyllum var. nikoense Maxim. (≡Cynanchum nikoense (Maxim.) Makino; Japanese: tsuru-gashiwa) which belong to the basal lineage of the clade “Vincetoxicum s.str.”.

These three taxa have been recognized in several publications so far, including the current Japanese flora. Recently, the author introduced V. magnificum in Curtis’s Botanical Magazine, but the name is not legally published according to the International Code of Nomenclature.

The species was first published by Nakai (1937) as C. magnificum Nakai, in connection with a taxonomic study of the related species V. macrophyllum (as Cynanchum grandifolium Hemsl.) and V. macrophyllum var. nikoense (as Cynanchum nikoense (Maxim.) Makino).

In the publication, the name C. magnificum Nakai was proposed for the “tachi-gashiwa” population distributed in the Kanto region of Honshu, Japan, but no Latin description, diagnosis or even indirect reference to a previous description was given. Therefore, the name C. magnificum Nakai is a nomen nudum (ICN Art. 38.1 and 39.1).

Later, based on this nomen nudum, Kitagawa (1959) published V. magnificum (Nakai) Kitag.; therefore, this combination was not validly published. Furthermore, the name cannot be considered a novum species, “Vincetoxicum magnificum Kitag.”, because it is not accompanied by a description, diagnosis or reference to a previously published Latin description or diagnosis.

In the present study, the Japanese species “tachi-gashiwa” was validly described as V. nakaianum K.Mochizuki & Ohi-Toma with a detailed description. In this case, the proposed name is not “nomen novum” but “species nova” because C. magnificum and V. magnificum have never been legally published.

V. nakaianum is morphologically similar to V. macrophyllum but is distinguished by erect stems ending in inflorescences and larger flowers, green to brownish, 10-15 mm in diameter. (vs. dark purple flowers and 4-5 mm in diameter) with glabrous crowns (vs. villi).

Flowering March-May and fruiting June-February. Elevation 100-850 m. This species grows in Japanese cedar plantation forests and deciduous forests dominated by Fagus japonica Maxim., Abies firma Siebold & Zucc., Quercus L., Acer L., and Carpinus L. The species epithet is given in honor of Prof. Takenoshin Nakai (1882-1952).

Original research

Mochizuki K, Nemoto S, Murata J, Ohi-Toma T (2024). Vincetoxicum nakaianum (Asclepiadoideae, Apocynaceae), a new species from Japan for Cynanchum magnificum Nakai, nomen nudum. PhytoKeys 247: 191-201, DOI:10.3897/phytokeys.247.125070

Dlium theDlium
Labels:

Popular Posts

Bugang (Clerodendrum calamitosum)

Bugang ( Clerodendrum calamitosum ) is a species of plant in the Lamiaceae family. It is an erect shrub, growing up to 1 meter tall, with cylindrical, green stems and white hairs. The leaves are opposite. The leaf blade is oval, wavy, with a central main vein with numerous pinnate minor veins, and serrated margins. The leaves are up to 9 cm long and 7 cm wide. The petiole is up to 2 cm long. The flowers are star-shaped, white, up to 3 cm in diameter and up to 6 cm in total length. The fruit is round, dark green, turning black when ripe. TAXON Kingdom: Plantae Phylum: Tracheophyta Subphylum: Angiospermae Class: Magnoliopsida Order: Lamiales Family: Lamiaceae Subfamily: Ajugoideae Genus: Clerodendrum L. in Sp. Pl.: 637 (1753) Species: Clerodendrum calamitosum L. in Mant. Pl. 1: 90 (1767) HETEROTYPIC SYNONYMS Clerodendrum fastigiatum (W.Hunter ex Ridl.) H.J.Lam in Verben. Malay. Archip.: 317 (1919) Volkameria alternifolia Burm.f. in Fl. Indica: 137 (1768) Volkameria fastigiata W.Hunter...
Read more

Plumeria rubra and Plumeria obtusa, the differences

SPECIES HEAD TO HEAD - The genus frangipani trees ( Plumeria Tourn. ex L.) has only 18 officially recorded species and two very similar species, frangipani ( Plumeria rubra L.) and white frangipani ( Plumeria obtusa L.). Both have the same habitus, flowers and fruits and are difficult to distinguish. The leaves of both species have slightly different shapes. Therefore, the leaves are very important to distinguish the two species, especially the shape of the tip. P. rubra has simple, lanceolate leaves with acute tips. P. obtusa has simple, elliptic leaves with rounded tips. By Aryo Bandoro Founder of Dlium.com . You can follow him on X: @Abandoro . Read more: Plumeria rubra Plumeria obtusa
Read more

Durian (Durio zibethinus)

Durian ( Durio zibethinus ) is a species of tropical plant in Malvaceae, an annual tree, everlasting green but there are certain times to grow new leaves after the fruiting period is over, popularly called "king of fruit" and considered a controversial fruit where many people like, but some others are even fed up with the scent. D. zibethinus grows to 25-50 m, reddish brown bark and irregular peeling, leafy and stretched canopy. The leaves are oval shaped to lanceolate, 10-15x3-4.5 cm, sitting alternately, stemmed, taper or blunt base and taper-pointed sloping, bright green upper side, the lower side covered with silver or golden scales. Flowers and fruit Flowers appear directly on the trunk or old branches at the proximal, clustered in panicles containing 3-10 florets or flat-shaped florets. Rounded flower buds, 2 cm in diameter and long stem. Tubular petals, 3 cm long, additional petals split into 2-3 round lobes. Crown shaped spatula with a length of 2 times the ...
Read more