Nordic Journal of Botany 29: 601Á604, 2011 doi: 10.1111/j.1756-1051.2011.01174.x, # 2011 The Authors Nordic Journal of Botany # 2011 Nordic Society Oikos Subject Editor: Henrik Ỉrenlund Pedersen Accepted March 2011 Lysimachia vietnamensis and L verbascifolia spp nov (Primulaceae) from Vietnam Phan Ke Loc and Hu Chi-Ming P K Loc, Faculty of Biology, Hanoi Univ of Science, Vietnam National Univ., Hanoi, Vietnam Á C M Hu (huqm@scbg.ac.cn), South China Botanical Garden, the Chinese Academy of Sciences, CN-510650 Guangzhou, PR China Two new species of Lysimachia (Primulaceae), L vietnamensis L K Phan & C M Hu and L verbascifolia C M Hu & K L Phan from Vietnam are described and illustrated During the past fifteen years a continuing program on ‘Biodiversity survey and plant conservation of Vietnam’ has been carried out jointly by the ‘Vietnam botanical conservation program’, the Institute of Ecology and Biological Resources (IEBR) of Vietnam, the Missouri Botanical Garden (MBG), and with the participation of many national and international institutions and organizations The field exploration site is located in northern Vietnam, a hotspot of biodiversity in southeastern Asia, and more than 27 thousand collection numbers of higher vascular plants have been collected While identifying the species of the genus Lysimachia, two new species growing in limestone areas were found as described in this paper With respect to the floral structure, the two new species clearly belong to subgenus Idiophyton Hand.-Mazz with the characters proposed by Chen and Hu (1979) and Hao et al (2004); basifixed anthers, much longer than the filaments and usually open by apical pores The genus as a whole is almost cosmopolitan, but exhibits endemism The subgenus Idiophyton is presumed to be the most primitive group of the genus, with its greatest concentration of species and diversity confined to south Yunnan, Guizhou and Guangxi in China, as well as northern Vietnam In this area, especially in the limestone hills, endemism is very high Both new species have a narrow distribution and occur as isolated individuals in suitable habitats Hu (1992) recognized fourteen species of Lysimachia in Vietnam, and together with the two new taxa decsribed here, the number of species has increased to sixteen Lysimachia vietnamensis L K Phan & C M Hu sp nov (Fig 1) Species L asperae Hand.-Mazz in sectione Apodanthera affinis, a qua floribus majoribus, pedicellis longioribus, lobis calycis subulato-lanceolatis praeter alia signa distinguitur Type: Vietnam Bac Kan Province: Na Ri District, Liem Thuy Commune, hills east of Na Bo Village, ca 21857’N, 106805’E, ca 702 m a.s.l 15 Jul 2004 Daniel E Atha, Nguyen Tien Hiep and Pham Van The DA4852 (holotype: HN, isotype: NY, IBSC) Perennial herb, 25Á40 cm tall Stems erect, quadriangular, ca 1.5 mm in diameter, more or less woody at base, glabrous, much branched Branches slender, 4Á30 cm long, spreading or reclining, bearing abbreviated branchlets in axils of leaves; branchlets 1Á4 mm, 2Á4-leaved Leaves alternate, papery, variable in size, those on stems and branches broadly elliptic to orbicular-elliptic, 9Á15 )6Á10 mm, apex apiculate to shortly acuminate, base attenuate into a 1Á4 mm long petiole, abaxial surface glabrous, adaxial surface initially with a few appressed, bristle-like hairs, glabrescent; margins ciliate, with short bristle-like hairs, appearing minutely serrulate; lateral veins 2Á3 on each side of midvein, obscure on both surfaces Leaves on abbreviated branchlets smaller, broadly ovate to suborbicular, 3.5Á7.0 )3Á5 mm Flowers solitary, axillary; pedicels very slender, 8Á12 mm long, longer than the subtending leaves, glabrous, with a few minute and scattered glands Calyx ca 4.8 mm, divided nearly to the base; lobes subulate-lanceolate, less than 0.5 mm broad at the base, glabrous outside, sparsely and minutely glandular inside Corolla pale yellow, united in the lower 0.3Á0.5 mm; lobes narrowly lanceolate, 5.0Á5.5)1.0 mm, apex acute, glabrous Stamens adnate to the base of the corolla, antepetalous; filaments ca 0.5 mm long, connate basally into a ring and fused with corolla, free parts less than 0.2 mm long; anthers basifixed, linear-lanceolate, ca 3.5 mm long, base sagittate, opening by apical pores Ovary ovoid, glabrous; style filiform, ca 4.8 mm long; stigma punctiform 601 Figure Lysimachia vietnamensis L K Phan & C M Hu sp nov (A) habit, (B) flower, (C) calyx, (D) corolla opened up showing stamens, (E) anther, (F) pistil Capsule globose-ovoid, 2.5Á3.0 mm in diameter, pale brown, splitting in valves when mature Distribution, habitat and phenology Lysimachia vietnamensis is so far known only from the type locality on the hills east of Na Bo Village (ca 21857’N, 106805’E) in Liem Thuy Commune, Na Ri District, Bac Kan Province, Vietnam It grows on the margin of wet evergreen broad-leaved forests at 700 m a.s.l., occurring as isolated individuals on a rocky ridge composed of crystalline marble-like highly eroded limestone Flowering and fruiting occur in July, the fertile structures represented by a complete maturation sequence ranging from immature buds to ripe fruits 602 Similar species Lysimachia vietnamensis closely resembles L aspera Hand.Mazz., a species endemic to Guangxi, China, but is easily distinguished by its longer pedicels, larger flowers, and linear-lanceolate calyx-lobes (Chen and Hu 1979, 1989, Hu and Kelso 1996) Lysimachia verbascifolia C M Hu & L K Phan sp nov (Fig 2) Inter species descriptas tantum cum L pilosa Fletcher et L grandifolia Hemsl comparanda, a quibus floribus in axillis foliorum congestorum solitariis, pedicellis multo longioribus inter alia recedit Type: Vietnam Thanh Hoa Province: Quan Hoa District, Phu Le Commune, Hang Village, around point Figure Lysimachia verbasifolia C M Hu & L K Phan sp nov (A) habit, (B) calyx, (C) corolla opened up showing stamens, (D) anthers showing dorsal and ventral surfaces, (E) pistil 21831’32’’N, 105804’54’’E, 350Á500 m a.s.l 18 Aug 2010, Phan Ke Loc and Ha Van Dan P 10982 (holotype: HN, isotype: IBSC, MO, LE) Perennial herbs; stems erect from a geniculate base, 4Á10 cm tall, 3Á5 mm in diameter,9woody at base, unbranched, villous Leaves alternate, usually 4Á8 mm apart, the upper 4Á6 leaves crowded at apex of stem, apperaing subverticillate; petioles 3Á6 cm long, grayish villous; leaf blade elliptic to broadly elliptic, 7Á17 )3.5Á8.0 cm, base broadly cuneate, apex obtuse, margin entire, ciliate, grayish villous on both surfaces, initially very densely hairy, but becoming sparser on adult leaves; lateral veins 6Á8 on each side of midvein, densely grayish villous Flowers subumbellate, to many crowded in a terminal leaf-whorl; pedicels slender, unequal, 1Á4 cm long, elongating to 4Á7 cm in fruit, pilose; in the next growing season the growth of the stem continues apically by forming a new leaf whorl, then the fruiting pedicels become axillary in leaf scars or remaining leaves under the terminal leaf whorl Calyx ca mm long, divided nearly to the base; lobes lanceolate, 9)2 mm, 5-veined, sparsely pilose outside Corolla pale yellow, divided nearly to the base; lobes oblong-lanceolate, 11.0Á12.0 )3.5 mm, apex acute Stamens 5; filaments slender, connate basally into a ring, free parts ca mm long; anthers ca mm long, gradually narrowed upward from a cordate base, basifixed, opening by apical pores Capsule globose, ca mm in diameter, pale brown, splitting in valves when mature; persistent style slender, 8Á9 mm long Distribution, habitat and phenology Lysimachia verbascifolia is so far only known from the type locality on the hills of Hang Village (21831’32’’N, 105804’54’’E), in Quan Hoa District, Thanh Hoa Province, Vietnam and one locality nearby It is a lithophytic herb, growing clustered in small groups in disturbed primary evergreen seasonal broad-leaved lowland forest, 603 on very steep rocky slopes and cliffs composed of crystalline marble-like highly eroded limestone at about 350Á650 m a.s.l Flowering occurs in JulÁOct, fruiting in DecÁMar Acknowledgements Á The authors thank the Vietnam Botanical Conservation Program, Ministry of Science and Technology, Vietnam, National Science Foundation USA and Fauna and Flora International, Indochina Program for funding the field trips, and thanks also to Mrs Liu Yun-xiao for the excellent line drawings Similar species Lysimachia verbascifolia is quite distinct from all species known to us in subgenus Idiophyton; its morphological affinity is with L grandifolia Hemsl and L pilosa Fletcher, but it is easily distinguished by its solitary flowers clustered in the axils of subterminal leaves (not forming peduncled umbels or corymbs) and longer pedicels (Chen and Hu 1979, 1989, Hu and Kelso 1996, Hu 1999) Additional specimens examined Vietnam Thanh Hoa Province: Quan Hoa District, Phu Le Commune, Hang Village, around point 20831?13??N, 105805?45??E, 450Á650 m a.s.l., Oct 2003, Leonid Averyanov, Phan Ke Loc and Nguyen Tien Vinh HAL 3788 (HN, IBSC); the same locality as type specimens, around point 20831’32’’N, 105804’54’’E, ca 350Á500 m a.s.l., Apr 2010, Phan Ke Loc, Ha Van Luc and Ha Van Nhuan P 10935 (HN, IBGC) 604 References Chen, F H and Hu, C M 1979 Taxonomic and phytogeographic studies on Chinese species of Lysimachia Á Acta Phytotax Sin 17: 21Á53 Chen, F H and Hu, C M 1989 Primulaceae (1) Flora Reipubl Pop Sin Vol 59 Á Science Press, pp 1Á133 Hao, Y et al 2004 Molecular phylogeny of Lysimachia (Myrsinaceae) based on chlororplast rbdL-F and nuclear ribosomal sequences Á Mol Phylogenet Evol 31: 323Á339 Hu, C M 1992 Primulaceae Á In: Morat, A (ed.), Flore du Cambodge, du Laos et du Vietnam, 26 Mus Natl Hist Nat., pp 115Á144 Hu, C M 1999 Primulaceae Á In: Santisuk, T and Larsen, K (eds), Flora of Thailand Vol 7, part one The Forest Herbarium, R For Dept, pp.155Á165 Hu, C M and Kelso, S 1996 Primulaceae Á In: Wu, Z Y and Raven, P H (eds), Flora of China Vol 15 Science Press, Miss Bot Gard Press pp 39Á78 ... Flowering and fruiting occur in July, the fertile structures represented by a complete maturation sequence ranging from immature buds to ripe fruits 602 Similar species Lysimachia vietnamensis. .. mm in diameter, pale brown, splitting in valves when mature Distribution, habitat and phenology Lysimachia vietnamensis is so far known only from the type locality on the hills east of Na Bo Village... Ministry of Science and Technology, Vietnam, National Science Foundation USA and Fauna and Flora International, Indochina Program for funding the field trips, and thanks also to Mrs Liu Yun-xiao