Proposal to conserve the name Machilus (Lauraceae)

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tion one of Rumphius's species (Machilus species quarta ... Cat. n. 2607, A ex parte, B, F.” According to Hooker (l.c.: 859–860), who first clarified Nees's original.
Yang • (1820) Conserve Machilus

398. 1975), and later Stace (New Fl. Brit. Isles: 673. 1991) considered it the correct name, but these are the only mentions of A. ×pseudopyramidalis in any Flora. In attempting to typify this name, we have searched for Schur materal in all possible herbaria (B, BP, BRNU, E, GOET, K, L, LW, MW, NA, P, PC, PH, PL, W, WU), and have not found any original material for lectotypification. We have therefore chosen as neotype a specimen from León, Spain that agrees with the description of A. pseudopyramidalis in being similar to A. pyramidalis, yet has stolons like A. reptans. The specimen is identifiable with A. × hampeana. Thus both A. ×rotundifolia and A. ×pseudopyramidalis apply to the same hybrid formula, i.e., A. pyramidalis × A. reptans, as A. ×hampeana, the name that has been consistently used for this hybrid for over a century, e.g., by Fiori (Nuov. Fl. Ital. 2: 401. 1926), Fournier (Quatre Fl. Fr.: 813. 1961), Ball (l.c.), Gams (in Hegi, Ill. Fl. Mitt.-Eur., ed. 2,

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5(4): 2548. 1975), Stace (l.c., 1975), De Langhe & al. (Nouv. Fl. Belg. Luxemb. N. France, ed. 2: 474. 1978; ed. 4: 560. 1992), Clapham & al. (Fl. Brit. Isl., ed. 3: 419. 1987). Ajuga ×rotundifolia was never treated as a hybrid, only as a species or a subspecies of A. pyramidalis, and A. ×pseudopyramidalis has only once been accepted in recent literature. However, according to ICBN Arts. 11.4 & 11.9, since the names A. ×rotundifolia and A. ×pseudopyramidalis have priority over A. ×hampeana and both apply to the same hybrid formula (Art. H.4.1) the earliest of these names (A. ×pseudopyramidalis) would have to be adopted for this nothospecies. However, to preserve nomenclatural stability in accordance with Art. 14.2, and avoid the displacement of a well-established and widespread name, the appropriate solution is to propose A. ×hampeana for conservation against both A. ×pseudopyramidalis and A. ×rotundifolia to avoid a change in nomenclature that will only cause conflict.

(1820) Proposal to conserve the name Machilus (Lauraceae) with a conserved type Yong Yang State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, 20 Nanxincun, Xiangshan, Beijing, China. [email protected]

(1820)

Machilus Rumph. in Lamarck, Encycl. 3: 668. 13 Feb 1792, nom. cons. prop. Typus: M. odoratissima Nees (‘odoratissimus’), typ. cons. prop.

Machilus has generally been attributed to Nees (in Wallich, Pl. Asiat. Rar. 2: 61, 70. 1831) and includes ca. 90 known species (Y. Yang, unpub. data). Although Long (in Notes Roy. Bot. Gard. Edinburgh 41: 505–522. 1984), Rohwer (Fam. Gen. Vasc. Pl. 2: 366–391. 1993), and Li (Woody Fl. Taiwan: 224. 1963) followed Kostermans (in Reinwardtia 6: 189–194. 1962; and in Ann. Missouri Bot. Gard. 77: 545–548. 1990) in incorporating Machilus into Persea, Rohwer (l.c.) and Kostermans (l.c., 1990) made clear at the same time that the two are different from each other both in morphology and distribution and retained subgeneric status for Machilus within Persea Mill. (viz. Persea subg. Machilus Kopp.). Wei & Tang (in Acta Phytotax. Sin. 44: 437–442. 2006) further clarified the major differences between Machilus and Persea. Machilus is currently applied to Asiatic plants of Lauraceae bearing bisexual flowers, persistent tepals equal or subequal in length and reflexed in fruits, and presence of prominent circular bud scale scars at the base of annual twigs (Meissner in Candolle, Prodr. 15: 39. 1864; Bentham & Hooker, Gen. Pl. 3: 156. 1880; Hooker, Fl. Brit. India 5: 136. 1890; Lee, Fl. Reipubl. Popularis Sin. 31: 7. 1979; Ohwi, Fl. Jap.: 469. 1984; Liao, Tax. Revis. 652

Lauraceae Taiwan: 111. 1988 and Fl. Taiwan, ed. 2, 2: 477. 1996; Wei & Tang, l.c.). This generic name is however found to be problematic in its nomenclature. Rumphius (Herb. Amboin. 3: 70, t. 40–42. 1743) first used Machilus as a plant name, but it was Desrousseaux (in Lamarck, Encycl. 3: 668. 1791) who first published Machilus after 1753 providing a summary of Rumphius’s account of the genus. Desrousseaux did not provide a generic description nor did he publish any species names within it, noting that “Rumph désigne sous ce nom des arbres qui paroissent fort différens les uns des autres, & jusqu’à présent inconnus des Botanistes” [Rumphius refers under this name to trees that seem very different from one another, & until now unknown to botanists]. The publication of Machilus in Desrousseaux (l.c.) was, however, validated on the basis of his reference to Rumphius (l.c), in which there is a brief diagnosis of the genus (“Machilus satis alta & crassa est arbor, quae dividitur in marem & feminam” [Machilus is a rather tall and thick tree which is divided into male and female]). This diagnosis is meaningful in determination of the plants as “tree” and “divided into male and female”. The characteristic “tree” can be dated back in plant classification to Theophrastus in De Historia Plantarum (Davis & Heywood, Princ. Angiosp. Taxon. 1963), and the concept of dioecism, separate male and female plants, was elucidated by Camerarius as early as 1694 in De sexu plantarum epistola. Rumphius (l.c.) surely knew this concept very well and was

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evidently seeking to characterise the genus Machilus by referring to these two features in his description. Although not diagnostic in Lauraceae today, they were evidently intended as such by Rumphius. This Rumphian diagnosis, taken with the species descriptions, was important in the identification of Rumphian original materials (Merrill, Interpr. Herb. Amboin.: 234, 236, 519. 1917; Kostermans, l.c., 1962 & 1990). I conclude, therefore, that Rumphius’s diagnosis satisfies the requirements of Art. 32.1(d) of the ICBN (McNeill & al. in Regnum Veg. 146. 2006) for valid publication of the generic name. Because Desrousseaux ascribed the name Machilus to Rumphius and because the validating description is that of Rumphius, the name must be attributed not to Desrousseaux but to Rumphius (in Lamarck, l.c.) (Art. 46.2 of the ICBN). Machilus Rumph. represents in fact a mixture probably of four different species in three different genera (see below). The valid publication of Machilus Rumph. in Lamarck has long been ignored and the name Machilus Rumph. is missing in such important works on Lauraceae as Bentham & Hooker (l.c.), Allen (in J. Arnold Arbor. 17: 376. 1936), Lee (l.c.), and Wei & al. (Fl. Guangxi 1: 224. 1991), and in Index Kewensis. That the name has been ignored might be because of the lack of a description and any named species by Desrousseaux (l.c.), but perhaps more importantly because of the immediate recognition (e.g., by Desrousseaux, himself) that Machilus Rumph. applied to an apparently discordant set of species leading to its rejection under the nomenclatural conventions of that time. The name is contrary to the old “nomen confusum” rule expressed originally as rejection of a name “when the group which it designates embraces elements altogether incoherent” (Art. 51 (4) of the Vienna Rules: Briquet, Regles Int. Nomencl. Bot. 1906). Kostermans (l.c., 1962) first considered the name “not acceptable as it is confusing”, which was in accord with Art. 70 of editions of the ICBN up until the Seattle Code (Stafleu & al. in Regnum Veg. 82. 1972). But by 1990 Kostermans realised that with the deletion of the “nomen confusum” provisions (Art. 70) at the Leningrad Congress of 1975 rejection of the name was no longer nomenclaturally tenable and he accepted Machilus Rumph. as validly published, and lectotypified it by the name of a species of Litsea [viz. L. glutinosa (Lour.) C.B. Rob.] (Kostermans, l.c., 1990). Merrill (l.c.) gave the first attempt at an identification of the four species that Rumphius included in Machilus. In his opinion, Machilus I mas 68, t. 40, f. A and Machilus II femina 69, t. 40, f. B are probably a single undetermined species of Litsea, Machilus III media 70, t. 41 is Dehaasia media Blume and not Machilus peduncularis Nees as suggested by Nees (l.c.: 70), and Machilus IV minima 70, t. 42 is either a species of Machilus, under which he listed it, or possibly a species of Phoebe. Kostermans (l.c., 1962 & 1990) discusses the identity of Rumphius’s material further and concluded that Machilus Rumph. represents at least four different species of three different genera. He (l.c., 1990) agreed with Merrill (l.c.) that Machilus III media 70, t. 41 is Dehaasia media Blume, and Machilus I mas 68, t. 40, f. A belongs to Litsea glutinosa, but he concluded that Machilus II femina 69, t. 40, f. B and Machilus IV minima 70, t. 42 are two species not belonging to Lauraceae. He further stated that Machilus IV

Yang • (1820) Conserve Machilus

minima 70, t. 42 is probably a species of Ilex because of the presence of 5 perianth lobes and the shape of the fruit. Wei & Tang (l.c. 2006: 438) basically agreed with Kostermans (l.c., 1990) but believed that both Machilus I mas 68, t. 40, f. A and Machilus II femina 69, t. 40, f. B belong to Litsea glutinosa though they provided no more details than Kostermans (l.c., 1990). In short, no material included by Rumphius can be ascribed to Machilus as currently circumscribed. Machilus as a generic name was adopted again by Nees (l.c.) who also attributed the name to Rumphius. Under one of the four species that Nees recognised (M. odoratissima, published as “M. odoratissimus”) he included without question one of Rumphius’s species (Machilus species quarta minima) (and also another, Machilus species tertia media, as a doubtful synonym of his M. peduncularis). Nees’s publication of Machilus cannot, therefore, be considered that of an independent later homonym as he included an element of Machilus Rumph., a name that had no “original type” (Art. 48.1). Because of Nees’s inclusion of a Rumphius synonym, Kostermans (l.c. 1962: 189) selected M. odoratissima as type of “Machilus Nees” when he believed Machilus IV minima 70, t. 42 to be a real Machilus. However Kostermans (l.c. 1990: 545) later concluded that the Rumphius’s species (“quarta minima”) was not in fact a Machilus as currently understood and not even a member of Lauraceae, but possibly a species of Ilex. Because Nees (l.c.: 70) did not indicate a type for M. odoratissima, and his inclusion of Rumphian Machilus IV minima 70, t. 42 made the species a mixture though he described it mainly based on “Laurus odoratissima Wall. Cat. n. 2607”, M. odoratissima should be lectotypified. Number 2607 in “Wallich’s Catalogue” (Wallich, Numer. List. 1831) represents several gatherings (2607A, B, C, D, E, and F) and is again a mixture that belongs to different species. Nees (l.c.) recognised two varieties α and β within his M. odoratissima. For α he writes “Laurus odoratissima Wall. Cat. n. 2607, A ex parte, C, D, E. …”, and for β “Laurus odoratissima Wall. Cat. n. 2607, A ex parte, B, F.” According to Hooker (l.c.: 859–860), who first clarified Nees’s original materials, Wall. Cat. n. 2607A, C, and D belong to Machilus bombycina King ex Hook. f. ( ≡ Machilus gamblei King ex Hook. f.), Wall. Cat. n. 2607E to Machilus kurzii King ex Hook. f., whereas Wall. Cat. n. 2607B & F are authentic Machilus odoratissima Nees as the name has since been applied. In doing so, Hooker (l.c.: 859–860) implicitly typified Machilus odoratissima Nees with Wallich Cat. n. 2607B & F. Because of this and because the 2607F has wrong locality information, Machilus odoratissima should be formally lectotypified with “Wall. Cat. n. 2607B” to fit in well with both Nees’s diagnosis and our current taxonomic concept of the species. Machilus odoratissima Nees (“odoratissimus”) – Lectotype (designated here): India, Uttarakhand State: “in montibus prope Dheyra Dhoon [Dehra Dun] (idem [i.e., Wallich] 1825)”, Wallich 2607B (K-W!). Rumphius (l.c.) clearly referred to some dioecious plants when he described Machilus as a rather tall and thick tree which is divided into male and female. Machilus Rumph. is thus entirely different from our current knowledge of Machilus that has bisexual flowers but never unisexual flowers. As a 653

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Li & Zhang • (1821) Conserve Dalbergia sericea G. Don

result, no element of Machilus Rumph. is referable to the genus Machilus as circumscribed today. Kostermans (l.c.: 545. 1990) realised that Machilus Rumph. is a validly published name and typified it by Litsea glutinosa because the “male” (Litsea glutinosa) is the most elaborately described within Rumphian original materials. This is contrary to his earlier typification of “Machilus Nees” with M. odoratissima (Kostermans, l.c., 1962). This changed approach of typification will surely cause obstacle in application of the name Machilus. To retain its current usage, I propose here to conserve the name Machilus Rumph. with a conserved type, viz. M. odoratissima.

Acknowledgements

Thanks are due to J. McNeill for his valuable discussions, suggestions and editing of the manuscript, to J. Wiersema for his editing of the manuscript, to J.R.I. Wood and Y.F. Deng for their kind help on the type specimen of M. odoratissima. This work was supported by a project from the Chinese Academy of Sciences (KSCX2-YW-Z-067), Plant Specimen Digitization and Chinese Virtual Herbarium Establishment (2005DKA21401), and the National Natural Science Foundation of China (30600035).

(1821) Proposal to conserve the name Dalbergia sericea G. Don against D. sericea (Vent.) Spreng. (Leguminosae : Papilionoideae) Shi-Jin Li & Dian-Xiang Zhang* South China Botanical Garden, The Chinese Academy of Sciences, Guangzhou 510650, China. *dx-zhang@ scbg.ac.cn (author for correspondence)

(1821)

(H)

Dalbergia sericea G. Don, Gen. Hist. 2: 375. Oct 1832 [Dicot.: Legum.], nom. cons. prop. Lectotypus (vide Prain in J. Asiat. Soc. Bengal, Pt. 2, Nat. Hist. 70: 52. 1901): Nepal, Cheria ghuat hills, Hamilton (BM). Dalbergia sericea (Vent.) Spreng., Syst. Veg. 3: 193. Jan–Mar 1826 (Pongamia sericea Vent., Jard. Malmaison 1: sub t. 28. Dec 1803) [Dicot: Legum.], nom. rej. prop. Typus: Java. La Haye (G).

Dalbergia is a pantropical genus of Leguminosae with c. 250 species. In reviewing the species of Dalbergia from China, we came across a threat to the name Dalbergia sericea G. Don, which has consistently been accepted for a species native from northern India, Bhutan, northern Vietnam to southwestern China. There exists an overlooked earlier homonym, D. sericea (Vent.) Spreng., that first appeared in the 1826 edition of Systema Vegetabilium volume 3, based on Pongamia sericea Vent. (Jard. Malmaison 1: sub t. 28. Dec. 1803). The name has never been adopted since then however. Later authors either ignored the name (e.g., Dunn in J. Linn. Soc., Bot. 41: 169. 1912; Chen in Fl. Reipubl. Popularis Sin. 40: 118. 1984; Thothathri in Tax. Revis. Dalbergieae Ind.: 160. 1987) or treated it or its basionym, P. sericea, as a synonym of Millettia sericea (Vent.) Wight & Arn. ex Hassk. (e.g., Prain in Ann. Roy. Bot. Gard. Calcutta 10: 109. 1904; Adema in Blumea 45: 405−406. 2000), a treatment with which the present authors agree. According to Art. 53.1 of the ICBN (McNeill & al. in Regnum Veg. 146. 2006), G. Don’s name is illegitimate because it is a later homonym of D. sericea (Vent.) Spreng., and thus it cannot be used. 654

Prain (l.c., 1901) reduced the name Dalbergia hircina Buch.-Ham. ex Benth. to synonymy under D. sericea G. Don and this taxonomic treatment has been generally accepted. The correct name for the species is, therefore, the earliest legitimate one, Dalbergia hircina. Strict application of the rules concerning nomenclatural priority (ICBN Art. 11) would result in displacement of the well-established later name D. sericea G. Don by the little-known and long-synonymous name Dalbergia hircina. Conservation of the name D. sericea G. Don against D. sericea (Vent.) Spreng. (under ICBN Art. 14) would prevent this disadvantageous change and preserve the usage of D. sericea G. Don. Moreover, the rejection of D. sericea (Vent.) Spreng. would not affect the continued availability of Milletia sericea (Vent.) Wight & Arn. ex Hassk. (or indeed of Pongamia sericea Vent.), for a species that has not been included in Dalbergia for more than 150 years. Dalbergia sericea G. Don has been used continuously since it was published, whereas D. hircina has rarely been used since Hasskarl (Cat. Hort. Bot. Bogor.: 284. 1844) and Bentham (in Miquel, Pl. Jungh. 1: 256. 1852). The name D. sericea G. Don is adopted in most recent national and regional floristic works and taxonomic treatments (e.g., Thothathri, l.c.; Chen, l.c.; Grierson & Long, Fl. Bhutan 1(3): 654. 1987; Sanjappa, Legumes Ind.: 140. 1992; Niyomdham & al. in Fl. Camb., Laos Viêt-Nam 29: 40. 1997; Fu & al. in Higher Pl. China 7: 97. 2001; Kumar & Sane, Legumes S. Asia: 174–175. 2003; Internet websites, e.g., http://www.ars-grin.gov/cgi-bin/ npgs/html/taxon.pl?13168; ecological reports). To employ the correct yet little known name D. hircina and abandon the widely used name D. sericea will cause unnecessary instability in taxonomy. We thus propose to conserve the name Dalbergia sericea G. Don against its earlier homonym, Dalbergia sericea (Vent.) Spreng.