SMITHSONIAN CONTRIBUTIONS TO BOTANY NUMBER 47 Polynesian Plant Studies 6- 18 F. Raymond Fosberg and Marie-Helene Sachet SMITHSONIAN INSTITUTION PRESS City of Washington 1981 ABSTRACT Fosberg, F. Raymond, and Marie-Helene Sachet. Polynesian Plant Studies 6- 18. Smithsonian Contributions to Botany, number 47, 38 pages, 6 figures, 1981.- The thirteen short taxonomic studies on Polynesian plants presented here deal with the genera Tricholaena Schrader, Oxalis L., Claoxylon A. Jussieu, Abutilon Miller, Zehneria Endlicher, Terminalia L., Myrsine L., Geniostoma Forster, Rauvolfia L., Leucas R. Brown, Cyrtandra Forster, Dicrocephala L’Heritier and with a number of miscellaneous distributional and nomenclatural records in other genera. The paper is a continuation of Polynesian Plant Studies 1-5, Smithson- ian Contributions to Botany, number 21, issued 21 July 1975, and is precursory to floristic studies in Polynesia. OFFICIALPUBLICATION DATE is handstamped in a limited number of initial copies and is recorded in the Institution’s annual report, Smithsonian Year. SERIESCOVER DESIGN: Leaf clearing from the katsura tree Cercidiphyllum japonicum Siebold and Zuccarini. Library of Congress Cataloging in Publication Data Fosberg, Francis Raymond, 1908- Polynesian plant studies. (Smithsonian contributions to botany ; no. 21. 47.) I. , ., Includes bibliographies and index. 1. Botanv-Polvnesia-Classification. I. Sachet. Marie-Hdlkne. ioint author. 11. Title. 111. Series: Smithsonian Institution. Smithsonian’contributions to’ botany ; no. 21 [etc.] QKl.SZ747 no. 21 [QK473.P75] 581s [581.996] 74-20539 Contents Page Introduction ......................................................... 1 6 . Tricholaena Schrader (Poaceae) in the Pacific Islands ........... 1 7 . A New Woody Ox& L . (Oxalidaceae) from the Marquesas ...... 3 8 . A New Claoxylon A . Jussieu (Euphorbiaceae) from the Marquesas 5 9 . Abutilon Miller (Malvaceae) in Southeastern Polynesia and Samoa: The Abutilon sachetianum Group ................................ 6 10 . New Combinations in Zehneria Endlicher (Cucurbitaceae) ....... 11 11. Tenninalia L . (Combretaceae) in Eastern Polynesia ............... 13 12 . Further Notes on Myrsine L . (Myrsinaceae) in Eastern Polynesia . 18 13 . New Geniostoma J . R . & G . Forster (Loganiaceae) Taxa ........... 18 14 . A New RQUVO@QL . (Apocynaceae) from the Marquesas ......... 21 15 . Leucm R . Brown (Lamiaceae) in the Pacific Islands .............. 24 16. Observations on Cyrtandra J . R . & G . Forster (Gesneriaceae) in the Marquesas Islands ............................................ 26 17. Nomenclature of Dichrocephala integriflia (L.f.) 0. Kuntze (Asteraceae) ................................................... 33 18 . Miscellaneous Taxonomic and Distributional Notes ............. 35 Literature Cited ..................................................... 3% ... 111 Polynesian Plant Studies 6- 18 F. Raymond Fosberg and Marie-Helene Sachet Introduction work of the junior author, several field assistants, and facilitated close cooperation with other nat- Continuing exploration and study of the floras uralists engaged in their own projects in the same of Polynesian islands have turned up a number islands. The work of Alice R. Tangerini and of new plants, several of them quite remarkable. Christopher R. Reinecke in making the illustra- Of especial interest are a new woody species of tions, and of Dulcie A. Powell in dissecting and Oxulis of obscure relationships, a group of island sketching difficult specimens is gratefully ac- species of Abutilon with large showy calyces, a knowledged. Rauvofia, and several new Cyrtandra taxa. The The first five studies in this series were pub- genus Geniostoma continues to yield new species in lished as Smithsonian Contributiom to Botany, number the G. rupestre assemblage. Critical taxonomic and 21, issued 21 July 1975. As in that paper, we here nomenclatural studies of Tricholaena, Terminalia indicate, by citing collector’s names and numbers glabrata, Leucas, Cyrtandra, and Dichrocephala integri- in italics, whether we have examined the speci- folia are offered, providing correct identities and mens cited. The herbaria where the specimens names for groups that have been troublesome. are deposited are indicated by Lanjouw system Miscellaneous minor taxonomic notes and range herbarium symbols as listed in the sixth edition extensions are provided in study 18. of Index Herbariorum (Holmgren and Keuken, Material kindly furnished by Betsy Gagne, P. 1974). Additional symbols are Fo, for plants still A. Schafer, and W. R. Sykes has been of impor- in our hands, and LeB for the LeBronnec set of tance in these studies, as have been older collec- Marquesas specimens. tions loaned by the Laboratoire de Phandrogamie of the Museum d’Histoire Naturelle, Paris, and by the B. P. Bishop Museum, Honolulu. The 6. Tricholaena Schrader (Poaceae) hospitality and cooperation of the authorities of in the Pacific Islands’ the herbaria where we have visited are greatly appreciated. Travel and other expenses have been Tricholaena Schrader met in part by grants from the Smithsonian Tricholaena Schrader in Schultes, Mant., 2:8, 1824. Research Awards Program, and the Smithsonian Rhynchelytmrn Nees in Lindley, Nat. Syst., ed. 2, 446, 1836. Fluid Research Fund. A generous grant from the National Geographic Society supported the field Tricholaena and Rhynchelytrum are names applied to two closely related groups of panicoid grasses F. Raymond Fosberg and Marie-Helene Sachet, Department of Botany, National Museum of Natural History, Srnithsonian Institution, Wash- ington, D. C. 20560. ’ Fosberg sole author of study 6. 1 2 SMITHSONIAN CONTRIBUTIONS TO BOTANY widely distributed in Africa and Arabia. They supporting the almost word-for-word identity in are considered distinct genera by many modern the generic descriptions, except for the number of floristic writers. This seems to be largely on the stamens. We are unable to confirm from dried authority of C. E. Hubbard, who, as far as known material available the “lateral” emergence of the to us, has never published any discussion giving styles from the spikelet in Rhynchelytrum, probably the reasons for regarding them as distinct. from lack of specimens in exactly the right stage. This would not be cause for much interest on In Tricholaena tenertffae the styles emerge apically. the part of flora writers of other regions were it The number of stamens, 3 versus 2, is regarded not for the widespread introduction in warm as a specific difference within some grass genera, regions, including Polynesia and Micronesia, of a e.g., Sporobolus (Bor 1960:623; Clayton 1965:293) handsome but weedy ornamental grass of this but scarcely seems sufficient to separate genera affinity, usually called either Tricholaena rosea or without other correlated substantial differentia- Rhynchelytrum repens. In California and a few other tion. The lack of anything in the ensemble of places it is occasionally planted in gardens for its minor characters making up “habit” seems to us beautiful fluffy bright pink to old-rose panicles. especially significant. We therefore choose to rec- This is probably how it gained its present pan- ognize only one genus, for which Tricholaena tropical distribution outside its native Africa, as Schrader is the oldest and therefore the correct it does not seem to be highly regarded as a pasture name. grass. The change to the specific epithet repens has For the plant long known as Tricholaena rosea, been accepted as uncritically as that to the generic usage changed, first to Tricholaena repens on the name Rhynchelytrum. Hitchcock made the transfer authority of A. S. Hitchcock, then almost at once, on the basis of an examination of the type of to Rhynchelytrum roseum and then R. repens on the Saccharum repens by Pilger. Pilger said it was iden- authority of C. E. Hubbard. Acceptance of these tical with Tricholaena rosea (letter, 2 July 1934, chmges seems mostly to have been uncritical, filed in the type collection, U.S. National Her- following these authorities. Before accepting any barium). Willdenow’s description does not men- of the four available names, their taxonomic and nomenclatural status should be examined. A com- tion the characteristic red color of the hairs on parison of the descriptions of the two genera in the spikelets but says, “Flores geminati sessiles Phillips’ book (195 1: 103- 104) shows only one candidis obvallatis.” Hubbard, in a letter, dated character of more than trivial value that distin- 17 January 1935, filed with that from Pilger, guishes them: two stamens per floret in Tricho- equates the two, but in a later letter, restricts laena, three in Rhynchelytrum. A few minor features Rhynchelytrum repens to West African forms, refer- such as gibbosity versus slight curvature of the ring other African material to R. roseum. Agnes upper glume, and the presence or absence of a Chase (1950:947) regarded R. rosea as distinct, distinct tiny internode between the lower and saying, “Has been confused with R. repens (Willd.) upper glumes are regarded as diagnostic in Hub- C. E. Hubb., a pale flowered annual from West bard’s keys (e.g., in Hutchinson and Dalziel, Africa.” In the U.S. National Herbarium, where 1936:50 1). the two are not separated, there are a number of An examination of the available material of sheets of such a pale-flowered plant, which seems the two genera in the excellent grass collection of a distinct species, but which is not confined to the U.S. National Herbarium