Lotus roudairei Bonnet and taxonomic relation­ ships between African and North American species of the tribe Loteae (Papilionaceae) Tatjana E. KRAMINA Higher Plants Department, Biological Faculty, Moscow State University, 119899 Moscow, Russia. [email protected] Dmitry D. SOKOLOFF Higher Plants Department, Biological Faculty, Moscow State University, 119899 Moscow, Russia. [email protected] ABSTRACT A comparative analysis of morphological features in NW African Lotus rou­ dairei, N American Lotus sect. Simpeteria, and American Lotus sect. Microlotus (= gen. Acmispon s. str.) was carried out. According to the data obtained, these three taxa seemed not to form the distinct genus or subgenus KEYWORDS Lotus roudairei, Acmispon sensu P. LASSEN (1986). A new section Pseudosimpeteria with a Papilionaceae, single species, L. roudairei, is described within the Old World Lotus subgen. Loteae, Lotus. The relationships between Old World and New World Loteae are Africa, N America. briefly discussed. RÉSUMÉ Une analyse morphologique comparative de Lotus roudairei nord-ouest-afri­ cain, Lotus sect. Simpeteria nord-américain et Lotus sect. Microlotus (= gen. Acmispon s. str.) américain a été réalisée. En partant des données obtenues, il apparaît que ces 3 taxons ne peuvent pas former un genre (ou sous-genre) particulier, Acmispon sensu P. LASSEN (1986). Une section nouvelle MOTS CLÉS Lotus roudairei, Pseudosimpeteria, avec une seule espèce L. roudairei, est décrite dans le genre Papilionaceae, Lotus subgen. Lotus, répandu dans l'Ancien Monde. Les relations entre les Loteae, Loteae de l'Ancien Monde et ceux du Nouveau Monde sont brièvement dis- Afrique, N Amérique. sér. 3 • 1997 • 19(2) 321 Kramina T.E. & Sokoloff D.D. INTRODUCTION Generally, the native N American species of Lotus s.l. are distributed from Mexico to S The taxonomic boundaries of the genus Lotus Canada and from the Atlantic to Pacific coasts; remain one of the most complicated issues in the the only native S American species occurs in intetgenetic delimitation of the tribe Loteae. In a Chile. The section Simpeteria contains 2-3 btoad sense, the genus comprises, according to annual and 10 perennial species in the SW part diffetent views, from 100 species (POLHILL 1981) of U.S.A. (Arizona, California, Colorado, to 176 species (KlRKBRlDE 1994) on all conti­ Nevada, New Mexico, Texas, Utah), and in nents except the Antarctic. The majority of spe­ Mexico, south to Veracruz and Puebla. The spe­ cies occut in the Meditettanean tegion, cies tend to be geographically separated from Macaronesia, and in the western patt of North each othet, e.g. two endemic species occur in America, especially in California. All native Mexico, one in Nevada, and one in Arizona. The North-American species of Loteae belong to the center of diversity of sect. Simpeteria is located in genus Lotus in the broadest sense. Mexico and Arizona. The section Microlotus A number of authors disagree with the broad contains about 8 annual species primarily in concept of the genus Lotus and tend to bteak it Western N America (British Columbia, up into several separate genera. In particular the Washington, Oregon, California, Arizona, New taxonomic position of North-American species Mexico, and Mexico). One species, L. subpinna- has been disputed. The review of the discussion tus Lag., is however, restricted to Chile, and one was presented by OTTLEY (1923) and CALLEN species, L. unifoliolatus (Hook.) Benth. has a (1959). OTTLEY (1923) recognized four main wide area of disttibution, extending from approaches to the taxonomy of N American Mexico, Texas and Arkansas to British Columbia Loteae. and Manitoba, and from the Pacific coast to North and South Carolina. In contrast with sect. 1. All N American species should be included Simpeteria, sect. Microlotus has a center of diver­ in the Old World genus Lotus. sity in California, and all the species reported for 2. All N American species should be treated as a United States occur also in California. Even the distinct genus Hosackia Dougl. ex Benth. Chilean L. subpinnatus is very close to L. wrange- 3. American species should be excluded from lianus Fisch. & Mey. from California, and some­ Lotus of the Old World and segregated into seve­ times the two species ate merged. The members ral genera: Hosackia, Acmispon Rafl, Syrmatium of subgenera Hosackia and Syrmatium, which are Vogel, and Anisolotus Bernh. not the subject of this papet, occur in Western N 4. The genus Hosackia should include the America, from British Columbia and Idaho to majority of American species, whereas remaining Mexico. species should be left within the Old World genus Lotus. OTTLEY (1923) accepted a broad concept of the According to GlLLETT (1958), only one insigni­ genus Lotus and tecognized three subgenera in ficant trait separates Old Wotld Lotus species America: subgen. Hosackia Ottley (syn. gen. from American Loteae, viz. leaf morphology. Old Hosackia Dougl. ex Benth. s. stt.), subgen. World species have five leaflets, with the lower Acmispon Ottley (syn. gen. Acmispon Rafl, gen. pair (of which one leaflet is occasionally absent) Anisolotus Bernh.), and subgen. Syrmatium Ottley situated at the base of the tachis, simulating (syn. gen. Syrmatium Vogel). Species of the first foliaceous stipules, very close to the true stipules subgenus have membranaceous or foliaceous sti­ which, if present, are reduced to glands. Less pules, while in the remaining two subgenera they often, they have three leaflets, with petiolules but are glandulai. Subgen. Syrmatium differs from without petiole or rachis. American species have subgen. Hosackia and subgen. Acmispon by the three leaflets with a definite petiole or rachis, or indéhiscent fruits. Later OTTLEY (1944) recogni­ 4-19 leaflets, pinnately arranged, often alternate, zed two sections—Microlotus Benth. and the lowest one situated above the base of the Simpeteria Ottley—in subgen. Acmispon. tachis and well separated from the glandulat or 322 ADANSONIA, sér. 3 • 1997 • 19(2) Lotus roudairei (Papilionaceae) membranaceous stipules. GlLLETT (1958) noted The name "Acmispon roudairef is accepted by that "even this definition fails for L. roudairei LOCK (1989) and by GREUTER et al. (1989). On Bonnet from Morocco which has up to 6 alter­ the other hand, LEBRUN & STORK (1992) and nately pinnate leaflets, the lowest well above the KlRKBRlDE (1994) again place the species in the base of the rachis and separated from the glandu­ genus Lotus; it is not clear however whether these lar stipules just as in Hosackia" (p. 363). COSSON authors include L. roudairei in sect. Simpeteria. named this species "L. bosackioides" (in herb.) thus implying a similarity to American species. BONNET (1893), describing L. roudairei in accor­ MATERIAL AND METHODS dance with the rules of botanical nomenclature, also compared it with North American Hosackia. The work is based on the study of herbarium The species is distributed in the W of N Africa specimens from herbaria LE, MHA, and P. The (Morocco, Algeria, and Tunisia), and in adjacent following American species were studied: sect. parts of Tropical Africa. Simpeteria: L. argyraeus (Greene) Greene, MAIRE et al. (1935) described a new species, L. L. grandiflorus (Benth.) Greene, L. greenei Ottley, simonae Maire, Weiller & Wilczek from the SE L. mearnsii (Britton) Greene, L. oroboides foothills of the Anti-Atlas mountains in Morocco (Humboldt, Bonpland & Kunth) Ottley, L. rigi- and included it, along with L. roudairei, in the dus (Benth.) Greene, L. strigosus (Nuttal ex proposed new section Stipulati Maire, Weiller & Torrey & A. Gray) Greene, L. tomentellus Wilczek. Recognition of sect. Stipulati was based Greene, L. utahensis Ottley, L. wrightii (A. Gray) on a single feature, the presence of true stipules Greene; sect. Microlotus: L. denticulatus (Drew) reduced to small dark glands. MONOD (1980) Greene, L. humistratus Greene, L. micranthus justly noted that not only L. simonae and L. rou­ Benth., L. salsuginosus Greene, L. subpinnatus dairei, but a number of Old World Lotus species, Lag., L. unifoliolatus (Hook.) Benth. [L. purshia- demonstrated glandular stipules, and therefore nus (Benth.) Clements & Clements], L. wrange- rejected the sect. Stipulati. According to LASSEN lianus Fisch. & Mey. (1986), L. simonae and L. roudairei have nothing For the study of floral morphology flowers were in common except the structure of the stipules; placed for two days into a mixture of equal parts in floral and vegetative characters L. simonae is a of glycerin, ethyl alcohol and water, and then true Lotus. LASSEN (1986, 1989) accepted at least dissected. For the study of ovule arrangement two genera of N American Loteae, namely and orientation additional material was used, Hosackia and Acmispon. He recognized sect. namely the herbarium specimens from MW, and Simpeteria within the genus Acmispon in accor­ flowers of L. corniculatus L., L. krylovii Schischk. dance with OTTLEY'S classification, where the & Serg., L. ucrainicus Klok., fixed in 70% ethyl section was included in subgen. Acmispon. alcohol in the field from several locations in LASSEN (1986) transferred L. roudairei to European Russia, Ukraine, and Kazakhstan. Acmispon sect. Simpeteria (Ottley) Lassen making a new combination, Acmispon roudairei (Bonnet) Lassen. Since sect. Stipulati had been described RESULTS AND DISCUSSION earlier than sect. Simpeteria, he selected L. simonae as lectotype of sect. Stipulati so that the latter A comparative morphological study of Lotus name would not interfere with OTTLEY's epithet1. roudairei and New World Loteae does not sup­ port the conclusion of LASSEN (1986), that L. roudairei belongs to the N American sect. Simpeteria. 1. LASSEN also reported, that he had studied the lectotype of L. simonae In MPU. Lectotyplflcatlon Is, however, not needed, OTTLEY (1944) gave a short and clear diagnosis because the type specimen exists ("[Morocco, prov. Tatta.] In of sect. Simpeteria: "Herbae vel suffrutices; carina alveo lapldoso amnls Bouzezza ad septentr. oasis Tatta ad obtusa, quam alis breviore; vexillo sine ungue; radices merldlonales Anti Atlantis. 730 m. 3 apr. 1934. Maire et Wilczek.", PI).