臺灣博碩士論文加值系統

本論文主要針對臺灣細辛屬杜蘅組 (Asarum sect. Heterotropa)植物的系統分類處理、親緣關係與親緣地理模式進行探討。
在系統分類方面，本研究利用形值分析的方法重新檢視大花細辛複合群(Asarum macranthum complex)，結果顯示此複合群可區分成三個分類群，包括大屯細辛(A. taitonense)、大花細辛(A. macranthum)與其變種—罈花細辛(A. macranthum var. ampulliflorum)。而柱頭與花柱形態、花被筒內壁特徵和花被筒形狀被認為是區分臺灣產杜蘅組植物的重要特徵，根據這些特徵，可將臺灣產杜蘅組植物區分成三群：下花細辛群、大花細辛群與鴛鴦湖細辛群。然而，在nrDNA的ITS片段所建構的細辛屬植物親緣關係中，顯示臺灣產杜蘅組植物亦分為三個單系群，但是與形態的分群不一致。且發現與臺灣的種類最近緣的是產於日本琉球群島與九州及本州西南部的種類。
最後，在以臺灣杜蘅組TW支序群為對象的親緣地理研究上，發現TW支序群內各族群間遺傳結構呈現高度分化，此與其特殊之生長、傳粉與種子傳播模式有關。此外，根據巢狀支序親緣地理分析 (NCPA) 及最近共祖時間推估 (TMRCA) 的結果，推論在Bayesian skyline plot上所觀察到的族群擴張與瓶頸效應的事件，除更新世冰河期循環的作用外，可能分別導因於祖先族群入侵一新的環境，以及最近一次冰河期最大值時，極度乾冷的氣候及森林範圍退縮造成族群數量變少有關。
綜合上述研究結果。確認臺灣產杜蘅組植物共計有12個分類群，包括11種及1個變種，其中有10個種類為特有種。而根據親緣關係研究則顯示這些現生分類群的祖先可能源於中國東南部與日本之間的區域。而臺灣杜蘅組植物各分類群分化的因素，除受冰期與間冰期循環的影響外，其本身的生物特性，例如對生長環境因子的需求、繁殖與傳粉策略等，亦是主要的原因之一。

In this dissertation, I focused on the systematics, phylogeny and the process of species differentiation of Asarum section Heterotropa in Taiwan.
In the systematic study, I performed morphometric analyses to resolve the taxonomic problems in the A. macranthum complex. The results support that the complex should be treated as three taxa, A. macranthum, A. macranthum var. ampulliflorum and A. taitonense. The stigma and style morphologies, the patterns on the inner wall of perianth,
and the shape of the perianth-tube are the most important characters to identify the Taiwanese Heterotropa. Based on these characters, we divided all Taiwanese Heterotropa into three groups. However, this grouping is inconsistent with the grouping of the nrDNA ITS phylogenetic analysis. In addition, according to ITS phylogenetic tree, the closest relations of the Heterotropa species in Taiwan are with Ryukyu Islands and south Kyusyu.
Phylogeographical study on the Taiwan clade showed high
differentiation in the genetic structure among the populations in the Taiwan clade. The result may be due to the specific growth patterns, pollination mechanism and seed dispersal systems of this group. According to the results of nested clade phylogenetic analysis, time of the
most ancestor estimation and Bayesian skyline plot, I inferred the demographical history of the Taiwan clade should be resulted from populations invading a new environment and the influence of extremely VI dry and cold climate in Last Glacial Maximum.
In conclusion, I confirmed that there are twelve Heterotropa taxa in Taiwan, including 11 species and one variety, and ten of twelve are endemic. The ancestor of Heterotropa species in Taiwan originated from the area between Southeast China and Japan based on the phylogenetic
inference. In addition to the influence of Pleistocene climatic fluctuations, the main factors that affected the species differentiation of Taiwanese Heterotropa may be correlated with its biological characteristics, such as
the growth patterns, pollination mechanism and seed dispersal systems in this group.

致謝 I
摘要 III
英文摘要 V
目錄 VII
第一章、緒論 1
第一節、系統分類 2
第二節、親緣關係研究 7
第三節、親緣地理研究 10
第四節、研究目的 12
第二章、以形值分析探討大花細辛複合群之分類問題 17
第一節、前言 17
第二節、材料與方法 18
第三節、結果 20
第四節、討論 24
第五節、分類處理 27
第三章、臺灣產杜蘅組植物之親緣關係 55
第一節、前言 55
第二節、材料與方法 57
第三節、結果 60
第四節、討論 63
第四章、臺灣產杜蘅組植物之親緣地理研究關係 75
第一節、前言 75
第二節、材料與方法 76
第三節、結果 81
第四節、討論 90
第五章、結論 123
參考文獻 129
附錄一、作者近年來所發表的杜蘅組植物新種及新紀錄種 141

圖目錄
圖1-1東亞地區細辛屬杜蘅組植物之分布區域 14
圖2-1本研究針對大花細辛複合群所採樣之28 個地點的地理分布圖 38
圖2-2大花細辛複合群所量測的各花部特徵位置圖 39
圖2-3大花細辛複合群三個不同的花部類型 40
圖2-4 大花細辛複合群157個樣本的主成分分析資料散布圖 (PCA scatterplots) 41
圖2-5 大花細辛複合群157 個樣本的主成分分析中第一主成分軸對第二主成分軸之資料散布圖(PCA scatterplots) 42
圖2-6 大花細辛複合群以PCA結果之分群進行區別分析的資料散布圖 43
圖2-7 大花細辛複合群的三種花型中，9 個量化特徵之盒型圖(boxplots) 44-45
圖2-8 第一型與第二型花在8 個量化特徵上的族群變異 46-47
圖2-9大花細辛複合群之地理分布圖 48
圖3-1 利用核醣體DNA-ITS 片段(ITS1+ITS2)以最簡約法則所建構之50% majority rule 的一致樹 67-68
圖3-2各支序群之最近共祖時間 69
圖3-3-1 臺灣、日本琉球群島與九州及本州西南部種類在更新世早期可能之分化途徑 70
圖3-3-2 臺灣與日本石垣島群島種類在更新世中期可能之分化途徑 70
圖4-1 細辛屬杜蘅組植物各種類族群採樣地點 96-97
圖4-2使用MEGA以鄰近接連法 (neighbor-joining) 所建構之葉綠體DNA單型親緣關係樹 98
圖 4-3-1. 白斑細辛()與神秘湖細辛()之cpDNA 單型的地理分布圖 99
圖 4-3-2. 大花細辛()、大屯細辛()、罈花細辛()與薩摩細辛()之cpDNA 單型的地理分布圖 100
圖 4-3-3. 插天山細辛 (▲)、鴛鴦湖細辛 (△)、太平山細辛 (▲)與
A. dissitum (▲)之cpDNA 單型的地理分布圖 101
圖4-4 針對葉綠體DNA 的62 個單型以Arlequin 所建構之最小關連網狀關係圖（依種類歸群) 102
圖4-5 針對葉綠體DNA 的62 個單型所建構的最小關連網狀關係圖進行巢狀支序圖繪製結果（僅顯示至第二層歸群) 103
圖4-6針對整個支序群所建構之BSL plot與臺灣與琉球地區近1.6Ma以來之地質歷史比較圖 104
圖4-7以巢狀支序分析的第三級分群為單位的Mismatch distribution之結果。A. III-1; B. III-2; C.III-3; D. Total clade 105-106
圖4-8臺灣杜蘅組植物各種類可能之分化途徑 107


表目錄
表1-1歷年來分類學者對臺灣產杜蘅組植物之分類處理沿革表 15
表2-1採集地點、各族群採樣數量，海拔及證據標本資訊 49
表2-2大花細辛複合群用於形值分析之特徵 50
表2-3 針對大花細辛複合群三種花型的157 個個體，利用11 個量化特徵與3 個質的特徵所進行主成分分析之結果 51
表2-4 針對大花細辛複合群以PCA 結果區分之三種花型與白斑細辛共157 個個體，利用10 個量化特徵所進行區別分析之結果 52
表2-5 以TUKEY HSD 測試來檢測以PCA 結果區分的三個花型在9 個量化特徵上是否具有顯著差異之結果 52
表2-6 在8個量化特徵上，第一型與第二型花個體的族群變異 53
表3-1建立親緣關係樹所用的物種、序列來源及產地 71-72
表3-2各支序群之最近共祖時間 73
表4-1本研究所使用的樣本之採集地點、樣本數(N)、證據標本樣與各族群之單型歧異度(h)、核苷酸歧異度(π)及單型(H) 108-111
表4-2本研究中62 個單型之變異位點資料 112-113
表4-3以巢狀支序親緣地理分析對所有資料與各第三級分群的過去族群變動歷史之推論結果 114
表4-4 以BEAST 軟體推估巢狀支序所有資料與第三級分群（III-2與III-3）的最近共祖時間(TMRCA) 114
表4-5 以山脈(A)、海拔(B)、氣候地理區(C)與物種(D)為分群單位所進行之AMOVA 分析結果 115
表4-6 巢狀支序歸群的第三級分群與全部資料之遺傳相關指數、中性檢測(Tajima’s D, Fu’s Fs test)與mismatch distribution 檢測 116
表4-7各種類中族群間之Pairwise Fst 117-121
表5-1臺灣產細辛屬杜蘅組植物名錄 128

Aoki, K., T. Matsumura, T. Hattori, and N. Murakami. 2006. Chloroplast DNA phylogeography of Photinia glabra (Rosaceae) in Japan. Amer. J. Bot. 93: 1852-1858.
Araki, Y. 1937. The species of Asarum in the Santan District. Acta Phytotax. Geobot. 6: 122-135.
Araki, Y. 1953. Systema generis Asari. Acta Phytotax. Geobot. 15: 33-36.
Avise, J. C. 2000. Phylogeography: The history and formation of species. Harvard University Press, Cambridge, Massachusetts, USA.
Cain, M. L., H. Damman & A. Muir. 1998. Seed dispersals and the Holocene migrate of woodland herbs. Ecological Monographs 68: 325-347.
Cheng, C.-Y. & C.-S. Yang. 1983. A synopsis of the Chinese species of Asarum (Aristolochiaceae). J. Arnold Arb. 64: 565-597.
Cheng, C.-Y. & C.-S. Yang. 1988. Asarum. In H.-S. Kiu & Y.-R. Ling (eds.), Fl. Reip. Pop. Sin. 24: 161-196. Science Press.
Comes, H. P. and J. W. Kadereit. 1998. The effect of Quaternary climatic changes on plant distribution and evolution. Trends in Plant Science 3: 432-438.
Coyne, J. A. and H. A. Orr. 2004. Speciation. Sinauer Associates, Inc. Sunderland, Massachusetts, USA.
Da Costa, A.F., P.J.F. Pena Rodrigues and M.D.G. Lapa Wanderley. 2009. Morphometric analysis and taxonomic revision of the Vriesea paraibica complex (Bromeliaceae). Bot. J. Linn. Soc. 159: 163-181.
De Faria, A.P.G., T. Wendt and G.K. Brown. 2010. A revision of Aechmea subgenus Macrochordion (Bromeliaceae) based on phenetic analyses of morphological variation. Bot. J. Linn. Soc. 162: 1-27.
Drummond, A. J. and A. Rambaut. 2007. BEAST: Bayesian evolutionary analysis by sampling trees. BMC Evol. Biol. 7:214.
Excoffier, L., G. Laval and S. Schneider. 2005. Arlequin ver. 3.0: An integrated software package for population genetics data analysis. Evol. Bioinform. Online 1:47-50.
Frajman, B. and B. Oxelman. 2007. Reticulate phylogenetics and phytogeographical structure of Heliosperma (Sileneae, Caryophyllaceae) inferred from chloroplast and nuclear DNA sequences. Mol. Phylogenet. Evol. 43: 140-155.
Fu, Y. X. 1997. Statistical neutrality of mutations against population growth, hitchhiking and background selection. Genetics 147: 915-925.
Hall, T. A. 1999. BioEdit: a user-friendly biological sequence alignment editor and analysis program for Windows 95/98/NT. Nucl. Acids Symp. Ser. 41: 95-98.
Hayata, B. 1915. Icones Plantanum Formosanarum, Vol.V. Bureau of Forestry. Taihoku (Taipei). Taiwan, pp. 139-150.
Henderson, A. 2006. Traditional morphometrics in plant systematics and its role in palm systematics. Bot. J. Linn. Soc. 151: 103-111.
Henderson, J. A. 2004. A multivariate analysis of Hyospathe (Palmae). Amer. J. Bot. 91: 953-965.
Heulsenbeck, J. P. & F. Ronquist. 2001. MRBAYES: Bayesian inference of phylogenetic trees. Bioinformatics 17: 754-755.
Hewitt, G. M. 2000. The genetic legacy of the Quaternary ice ages. Nature 405: 907-913.
Hewitt, G. M. 2004. Genetic consequences of climatic oscillations in the Quaternary. Phil. Trans. R. Soc. B. 359: 183-195.
Hong-Wa, C. 2008. Multivariate analyses of morphological characters of Leptolaena Thouars s.l. subgenera Mediusella and Xerochlamys (Sarcolaenaceae). Bot. J. Linn. Soc. 157: 559-574.
Hooker, J.D. 1888. Asarum macranthum. Curtis’ Bot. Mag. t. 7022.
Huang, S.-F. 1996. Asarum. In T.-C. Huang et al. (eds.), Fl. Taiwan 2nd edn. Vol. 2. Editorial Committee, Dept. Bot., NTU, Taipei, Taiwan, pp. 642-651.
Huang, S.-F., T.-H. Hsieh, and T.-C. Huang. 1995. Notes on the Flora of Taiwan (21) - The genus Asarum L. (Aristolochiaceae). Taiwania 40: 91-120.
Huang, S.-M., L. M. Kelly & M. G. Gilbert. 2003. Asarum. In: Wu Z.-Y., Raven P. H., editors. Flora of China, vol. 5. Beijing: Science Press, St. Louis: Missouri Botanical Garden Press. pp 246-258.
Iwanaga, M. and Y. Momotani. 1976. Inter- and intrapopulational variations in the peroxidase isozyme of Asarum nipponicum F. Maekawa. Bot. Mag. Tokyo 89: 93-98.
Jakob, S. S. and F. R. Blattner. 2006. A chloroplast genealogy of Hordeum (Poaceae): Long-term persisting haplotypes, incomplete lineage sorting, regional extinction, and the consequences for phylogenetic inference. Mol. Biol. Evol. 23: 1602-1612.
Johnson, L. A. and D. E. Soltis. 1994. MatK DNA sequences and phylogenetic reconstruction in Saxifragaceae s. str. Syst. Bot. 19: 143-156.
Kay, K. M., J. B. Whittall and S. A. Hodges. 2006. A survey of nuclear ribosomal internal transcribed spacer substitution rates across angiosperms: an approximate molecular clock with life history effects. BMC Evol. Biol. 6: 36.
Kelly, L. M. 1997. A cladistic analysis of Asarum (Aristolochiaceae) and implications for the evolution of herkogamy. Amer. J. Bot. 84: 1752-1765.
Kelly, L. M. 1998. Phylogenetic relationships in Asarum (Aristolochiaceae) based on morphology and ITS sequences. Amer. J. Bot. 85: 1454-1467.
Kelly, L. M. 2001. Taxonomy of Asarum section Asarum (Aristolochiaceae). Syst. Bot. 26: 17-53.
Kimura, M. 2000. Paleogeography of the Ryukyu islands. Tropics 10: 5-24.
Lai, M.-J. 1973. Revision of Rafflesiaceae, Balanophoraceae and Aristolochiaceae in Taiwan. Master’s thesis, Department of Forestry, National Taiwan University, Taipei, Taiwan.
Librado, P. and J. Rozas. 2009. DnaSP v5: A software for comprehensive analysis of DNA polymorphism data. Bioinformatics 25: 1451-1452.
Liu, T.-S. and M.-J. Lai. 1976. Aristolochiaceae. In H. L. Li et al. (eds.), Flora of Taiwan. Vol. 2. Epoch Pub. Co. Taipei, pp. 571-581.
Löhne, C. and T. Borsch. 2005. Phylogenetic utility and molecular evolution of the petD group II intron in basal angiosperms. Mol. Biol. Evol. 22: 317-332.
Lu, C.-T. 2001. A taxonomic study of Asarum L. (Aristolochiaceae) of Taiwan. Master’s thesis, National Taiwan Normal University, Taipei, Taiwan.
Lu, C.-T. and J.-C. Wang. 2009. Three new species of Asarum (section Heterotropa) from Taiwan. Bot. Std. 50: 229-240.
Lu, C.-T., C.-W. Chen and J.-C. Wang. 2009. Asarum yaeyamense Hatusima (Aristolochiaceae) newly found from northern Taiwan. Taiwan J. For. Sci. 24: 149-157.
Lu, C.-T., W.-L. Chou, S.-C. Liu and J.-C. Wang. 2010. Asarum satsumense (Aristolochiaceae), a new recorded species in Taiwan. Taiwania (accepted).
Ma, S. J. 1990. The geographical distribution and the system of Aristolochiaceae. Acta Phtotax. Sin. 28: 345-355.
Maddison, W. P. and D. R. Maddison. 2009. Mesquite: a modular system for evolutionary analysis. Version 2.72. http://mesquiteproject.org.
Maekawa, F. 1933. Japanese Asaraceae I-VII. J. Jap. Bot. 9: 39-46, 96-103, 174-181, 241-246, 281-285, 364-370, 505-512. [in Japanese]
Maekawa, F. 1934. Japanese Asaraceae VIII-IIX. J. Jap. Bot. 10: 358-362. [in Japanese]
Maekawa, F. 1936. Japanese Asaraceae. IX. J. Jap. Bot. 12: 28-34. [in Japanese]
Maekawa, F. 1952. Species-differentiation in North-western Kiusiu of Japan. J. Jap. Bot. 27: 1-6. [in Japanese]
Maekawa, F. 1963. Reduction in chromosomes and major polyploidy: their bearing on plant evolution. J. Fac. Sci. Univ. Tokyo, III, 8: 377-398.
Maekawa, F. 1978. Notes on Asarum and Heterotropa from Taiwan. J. Jap. Bot. 53: 289-299. [in Japanese]
Möller, M., L. M. Gao, R. R. Mill, D. Z. Li, M. L. Hollingsworth, M. Gibby. 2007. Morphometric analysis of the Taxus wallichiana complex (Taxaceae) based on herbarium material. Bot. J. Linn. Soc. 155: 307-335.
Okuyama, Y., N. Fujii, M. Wakabayashi, A. Kawakita, M. Ito, M. Wata-nabe, N. Murakami and M. Kato. 2005. Nonuniform concerted evolution and chloroplast capture: heterogeneity of observed introgression patterns in three molecular data partition phylogenies of Asian Mitella (Saxifragaceae). Mol. Biol. Evol. 22: 285-296.
Otieno, D. F., K. Balkwill and A. J. Paton. 2006. A multivariate analysis of morphological variation in the Hemizygia bracteosa complex (Lamiaceae, Ocimeae). Pl. Syst. Evol. 261: 19-38.
Padgett, J. E. 2004. Biogeographical, ecological, morphological, and micromorphological analyses of the species in the Hexastylis heterophylla complex. Master’s thesis, Appalachian State University, USA.
Roché, C. T. & F. A. Lang. 2008. Green-flowered Wild Ginger (Asarum wagneri Lu & Mesler). Kalmiopsis 15: 15-20.
Pedersen, H Ǽ. Species delimilation and recognition in the Brachycorythis helferi complex (Orchidaceae) resolved by multivariate morphometeric analysis. Bot. J. Linn. Soc. 162: 64-76.
Petit, R. J., I. Aguinagalde, J.-L. D. Beaulieu, C. Bittkau, S. Brewer, R. Cheddadi, R. Ennos, S. Fineschi, D. Grivet, M. Lascoux, A. Mohanty, G. Müller-Starck, B. Demesure-Musch, A. Palmé, J. P. Martin, S. Rendell and G. G. Vendramin. 2003. Glacial refugia: Hotspots but not melting pots of genetic diversity. Science 300: 1563-1565.
Posada, D., K. A. Crandall and A. R. Templeton. 2000. GeoDis: a program for the cladistic nested analysis of the geographical distribution of genetic haplotypes. Mol. Ecol. 9: 487-488.
Rogers, A. R. and H. C. Harpending. 1992. Population growth makes waves in the distribution of pairwise genetic differences. Mol. Biol. Evol. 9: 552-569.
SAS Institute Inc. 2002. JMP version 5.0.1. http://www.jmp.com.
Shen, C.-F. 1997. The Biogeography of Taiwan: 2. Some preliminary thoughts and studies. Ann. Taiwan Mus. 40: 361-450. (in Chinese with English summary)
Sibuet, J. C. and S. K. Hsu. 2004. How was Taiwan created? Tectonophysics 379: 159-181.
Slatkin, M. and R. R. Hudson. 1991. Pairwise comparison of mitochondrial DNA sequences in stable and exponentially growing populations. Genetics 129: 555-562.
Su, H.-J. 1985. Studies on the climate and vegetation types of the Natural forests in Taiwan (Ⅲ): A sheme of geographical climate regions. Quart. J. Chin. Forest 18(3): 33-44.
Sugawara, T. 1981. Taxonomic studies of Asarum sensu lato I. karyotype and c-banding pattern in Asarum s. str., Asiasarum and Heterotropa. Bot. Mag. Tokyo 94: 225-238.
Sugawara, T. 1988. Flora biology of Heterotropa tamaensis (Aristolochiaceae) in Japan. Pl. Sp. Biol. 3:7-12.
Sugawara, T. 1992. A taxonomic study of Heterotropa nipponica and H. savatieri ssp. pseudosavatieri (Aristolochiaceae) in the Shima Peninsula. Acta Phytotax. Geobot. 43: 15-26.
Sugawara, T. 1996. Chapter 9 Kanaoi. In Y. Wakanabe ed. Monograph of Luchdorfia Butterflies. Hokkaido University Press, Sapporo. pp. 172-181. [in Japanese]
Sugawara, T. 1998. A taxonomic study of Asarum megacalyx F. Maek. and related taxa (Aristolochiaceae) distributed in Niigata Prefecture and adjacent area of Japan. Acta Phytotax. Geobot. 49: 1-17.
Sugawara, T. 2003. Morphological and cytological variation in Asarum fauriei (Aristolochiaceae) in central and north Honshu, Japan. Acta Phytotax. Geobot. 54: 149-162.
Sugawara, T. 2006. Asarum. In: Iwatsuki K., et al., editors. Flora of Japan, vol. IIa. Kodansha. p 380.
Sugawara, T. and M. Ogisu. 1992. Karyomorphology of 11 species of Asarum (Aristolochiaceae) from Taiwan and mainland China. Acta Phytotax. Geobot. 43:89-96.
Sugawara, T., N. Fujii, K. Senni, and J. Murata. 2005. Morphological and karyological characteristics and phylogenetic relationship of Asarum cordifolium C. E. C. Fisch. (Aristolochiaceae) occurring in Myanmar. Acta Phytotax. Geobot. 56, 247-255.
Swofford, D. L. 2002. PAUP*4.0b10: phylogenetic analysis using pasimony (* and other methods), v. 4.0b10. Sinauer, Sunderland, Massachusetts, USA.
Taberlet, P., L. Gielly, G. Patou and J. Bouvet. 1991. Universal primers for amplification of three noncoding regions of chloroplast DNA. Pl. Mol. Biol. 17: 1105-1109.
Takasu, H. and S. Kawano, 2009. Life-history monographs of Japanese plants. 12: Asarum caulescens Maxim. (Aristolochiaceae). Pl. Sp. Biol. 24: 61-67.
Tamura, K., J. Dudley, M. Nei and S. Kumar. 2007. MEGA4: Molecular Evolutionary Genetics Analysis (MEGA) software version 4.0. Mol. Biol. Evol. 24:1596-1599.
Templeton, A. R. 1998. Nested clade analyses of phylogeographic data: testing hypotheses about gene flow and population history. Mol. Ecol. 7: 381-397.
Templeton, A. R. 2004. Statistical phylogeography: methods of evaluating and minimizing inference error. Mol. Ecol. 13: 789-809.
Templeton, A. R. and C. F. Sing. 1993. A cladistic analysis of phenotypic associations with haplotypes inferred from restriction endonuclease mapping. IV. Nested analyses with cladogram uncertainty and recombination. Genetics 134: 659-669.
Templeton, A. R., E. Routman and C. A. Philips. 1995. Separating population structure from population history: a cladistic analysis of the geographical distribution of mitochondrial DNA haplotypes in the tiger salamander, Ambystoma tigrinum. Genetics 140: 767-782.
Teng, L. S. 2007. Quaternary tectonics of Taiwan. Special publication of the central geographical survey. 18: 1-24.
Tougard, C., E. Renvoisé, A. Petitjean and J. P. Quéré. 2008. New insight into the colonization process of common voles: inferences from molecular and fossil evidence. PLoS ONE 3: e3532.
Watanabe K., T. Ohi-Toma, and J. Murata. 2008. Multiple in the Aristolochia kaempferi group (Aristolochiaceae): Evidence from reproductive isolation and molecular phylogeny. Amer. J. Bot. 95: 885-896.
Watanabe, K., T. Kajita, and J. Murata. 2006. Chloroplast DNA variation and geographical structure of the Aristolochia kaempferi group (Aristolochiaceae). Amer. J. Bot. 93: 442-453.
Whittemore, A. T. & T. T. Gaddy. 1997. Hexastylis. In Flora of North America. Vol. 3. http://www.efloras.org/florataxon.aspx?flora_id =1&taxon_id=115416.
Wu, C. M., C. Y. Huang, H. F. Chou, L. L. Tsai, and C. Na. 1974. Pharmacological study on Korean Asarum and Taiwanese Heterotropa. J. Taipei Med. Coll. 6: 1-46.
Yamaji, H., J. Yokoyama, H. Ohashi and M. Maki. 2006. Concordant clines and significant correlation between floral and pollen characters in Asarum heterotropoides var. heterotropoides (Aristolochiaceae). Pl. Syst. Evol. 259: 1-17.
Yamaji, H., T. Fukuda, J. Yokoyama, J.-H. Pak, C.-Z. Zhou, C.-S. Yang, K. Kondo, T. Morota, S. Takeda, H. Sasaki and M. Maki. 2007a. Reticulate evolution and phylogeography in Asarum sect. Asiasarum (Aristolochiaceae) documented in internal transcribed spacer sequences (ITS) of nuclear ribosomal DNA. Mol. Phylogenet. Evol. 863-884.
Yamaji, H., T. Nakamura, J. Yokoyama, K. Kondo, T. Morota, S. Takeda, H. Sasaki and M. Maki. 2007b. Morphological comparison of Asarum sect. Asiasarum (Aristolochiaceae) in Japan with special reference to multivariate analyses of flowers. J. Jap. Bot. 82: 57-78.
Yamane, K., K. Yano and T. Kawahara. 2006. Pattern and rate of indel evolution inferred from whole chloroplast intergenic region in sugarcane, maize and rice. DNA Res. 13: 197-204.
Yinger, B. 1983. A horticulture monograph of genus Asarum sensu lato, in Japan. Master’s thesis, University of Delaware. Newark, DE.
Yuasa, H. and F. Maekawa. 1976. Chromosomes of Asarum and Heterotropa (Aristolochiaceae) in the Ryukyu Islands. La Kromosomo II: 8-18.