(2731) Chloranthus elatior R. Br. in Bot. Mag.: ad t. 2190. 1 Nov 1820, nom. rej. prop.

Typus: non designatus.

The genus Chloranthus Sw. (in Philos. Trans. 77: 359. 1787) has about 18 species in East Asia, continental Southeast Asia, and through Malesia to New Guinea.

Chloranthus elatior was published by Robert Brown (in Bot. Mag. 48: ad t. 2190. 1820) although Verdcourt (in Kew Bull. 40: 217. 1985) suggested that it was not validly published as two species, one of which is C. elatior and the other C. inconspicuus Sw. (in Philos. Trans. 77: 360, t. 14. 1787), are distinguished together from a third species, C. monander R. Br. (l.c.). However, under the ICN Art. 38.1, there is no obligation for a description to be diagnostic, only that there be one. Brown does provide a description (actually a brief diagnosis) of C. elatior even though the descriptive material is exactly the same as that given for C. inconspicuus and both are distinguished primarily from the very concisely characterized C. monander. Verdcourt went on to argue that the name was actually published by Link (Enum. Hort. Berol. Alt. 1: 140. 1821), and were C. elatior to be considered not validly published by Brown, it would indeed have been first published by Link (l.c.), and the problems discussed below would remain. Link noted that his plant was sterile and came from cultivation in England. Link also questioned whether it was the same as C. erectus Sweet (Hort. Suburb. Lond.: 28. 1818), which, however, lacks a description and is not validly published. Believing that only the material cited by Link could be considered to be original, Verdcourt concluded that this material would have been destroyed in Berlin. However, the material on which it was actually published one year earlier by Brown has also not been traced. As the protologue does not distinguish the species from C. inconspicuus, as no provenance is given, and as no original material has been found, the identity of C. elatior cannot be established. Despite this, Backer & Bakhuizen van den Brink (Fl. Java 1: 175. 1964) used the name for a species in Java, and Rudall & al. (in Amer. J. Bot. 96: 67–82. 2009), in a paper on reproductive morphology, also referred to C. elatior. In these cases they used the name for the species that has generally been called C. erectus (Buch.‐Ham.) Wall. (Numer. List 230: no. 6881. 1832) although in neither case was this stated explicitly. Otherwise, C. elatior has not been much used in the literature and then primarily only in recent years and in works on secondary metabolites.

However, Kew's Plants of the World Online (http://www.plantsoftheworldonline.org/) explicitly places Cryphaea erecta Buch.‐Ham. (in Edinburgh J. Sci. 2: 11. 1825), the basionym of Chloranthus erectus (Buch.‐Ham.) Wall., in synonymy under Chloranthus elatior. Chloranthus erectus is widely used in the literature (e.g., Verdcourt, l.c. 1985, Fl. Males., ser. 1, 10: 131. 1986; Keng, Concise Fl. Singapore 1: 63. 1990; Carlquist in I. A. W. A. Bull. 13: 3–16. 1992; Verdcourt in Fl. Thailand 5: 425. 1992; Turner in Gard. Bull. Singapore 45: 51. 1993; Ng & Wee, Singapore Red Data Book: 279. 1994; Xia & Joël in Wu & Raven, Fl. China 4: 132. 1999; Kong & al. in Amer. J. Bot. 89: 940–946. 2002; Tan & al. in Davison & al., Singapore Red Data Book, ed. 2: 219. 2008; Chong & al., Checkl. Vasc. Pl. Fl. Singapore: 25, 119, 202. 2009; Rafidah in Fl. Penins. Malaysia, ser. 2, 1: 96. 2010; Ho & al. in Gard. Bull. Singapore 71(Suppl. 1): 76. 2019). The commonly given authorship of Chloranthus erectus as “(Buch.‐Ham.) Verdc.” (Verdcourt, l.c. 1985) and sometimes as “(Buch.‐Ham.) Sweet ex Wall.” must be corrected to “(Buch.‐Ham.) Wall.” as Wallich (l.c.) clearly based the name on Cryphaea erecta Buch.‐Ham. (l.c.) citing “Cryphaea erecta H. Ham.” as a synonym. The earlier use of Chloranthus erectus by Sweet (l.c.) is a nomen nudum, and Buchanan‐Hamilton makes no mention of it when publishing Cryphaea erecta. The type is Buchanan‐Hamiliton 98 (lectotype: E, effectively designated by Verdcourt, l.c. 1985).

A number of authors have referred to this species as Chloranthus officinalis Blume (Enum. Pl. Javae 1: 10. 1827). These include Blume (Fl. Javae 8: 13. 1829), Hooker (Fl. Brit. India 5: 100. 1886), and Ridley (in J. Straits Branch Roy. Asiat. Soc. 33: 128. 1900, Fl. Malay Penins. 3: 52. 1924). Verdcourt (l.c. 1985) and subsequent authors have treated this as a synonym of C. erectus.

Verdcourt (l.c. 1985) and Xia & Joël (l.c. 1999) noted that Chloranthus elatior could apply to the same species as C. erectus, and consequently would have priority, but were reluctant to displace the widely used name C. erectus when the synonymy was far from certain. A neotype could be designated to fix the application of C. elatior to the species usually called C. erectus but that would not serve nomenclatural stability given the widespread use of C. erectus. A neotype might alternatively be designated for C. elatior to typify it with material of another Chloranthus species, such as C. inconspicuus, that has priority over C. elatior, but the disadvantage of this strategy would be that the neotype could be overturned if Brown's original material were later to be found. Instead, we propose rejection of Chloranthus elatior to clarify that C. erectus should continue to be used.