ISSN 1346-7565 Acta Phytotax. Geobot. 71 (3): 187–199 (2020) doi: 10.18942/apg.202003
A Revised Infrageneric Classification of Old World Species of Dioscorea (Dioscoreaceae)
1,* 1 2 3 3 Hiroshi Noda , Shizuka Fuse , Jun Yamashita , Rachun Pooma , Manop Poopath , 1 1 Hiroshi Tobe and Minoru N. Tamura
1Department of Botany, Graduate School of Science, Kyoto University, Kitashirakawa-oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan. *[email protected] (author for correspondence); 2Institute of Plant Science and Resources, Okayama University, Chuo 2-20-1, Kurashiki-shi, Okayama 710-0046, Japan; 3The Forest Herbarium, Department of National Parks, Wildlife and Plant Conservation, Chatuchak, Bangkok 10900, Thailand
Dioscorea (Dioscoreaceae), a morphologically diverse genus, consists of more than 600 species distrib- uted worldwide. Recent molecular and morphological analyses allowed us to recognize two subgenera, Dioscorea and Helmia, and 19 Old World species groups (sections) in subgenus Helmia. In this paper we present a diagnostic key and taxonomic treatment for the subgenera and sections, including D. sect. Ta- mus (stat. nov.) and four new sections; Afroborderea, Perennia (validated here), Pseudoshannicorea and Pseudostenophora. Lectotype species for eleven sections; Enantiophyllum, Illigerastrum, Lasiophyton, Macrocarpaea, Macropoda, Madagascarienses, Orientali-asiaticae, Rhacodophyllum, Shannicorea, Stenophora and Syntepaleia, are also designated.
Keywords: Dioscorea, Dioscorea sect. Afroborderea, Dioscorea sect. Perennia, Dioscorea sect. Pseu- doshannicorea, Dioscorea sect. Pseudostenophora, Dioscorea sect. Tamus, Dioscorea subg. Helmia, Dioscoreaceae, lectotypification, taxonomy
Dioscorea (Dioscoreaceae), yams, are mostly used by combining all existing cpDNA sequence dioecious vines with twining stems (Fig. 1). data obtained in previous studies (Caddick et al. Based on their great morphological diversity, 2002a, Wilkin et al. 2005, Gao et al. 2008, Hsu et about 630 species have been recognized (WCSP al. 2013, Maurin et al. 2016, Viruel et al. 2016, 2019). Previous authors have proposed infrage- Couto et al. 2018) with our original data (Noda et neric taxa (23 to 58 sections and several subgen- al. 2020). era) and several separate genera (which were re- The resultant phylogenetic tree consisted of cently placed within Dioscorea based on molecu- eleven major clades (Fig. 2a), most of which fur- lar evidence) (Uline 1898, Knuth 1924, Burkill ther consisted of more than two strongly or mod- 1960, Huber 1998, for review see Caddick et al. erately supported subclades (Noda et al. 2020). 2002a, Noda et al. 2020). However, diagnostic As in previous studies (Wilkin et al. 2005, Viruel keys to the taxa (genera/subgenera/sections) dif- et al. 2016, 2018, Couto et al. 2018), Dioscorea fer greatly among the authors and no consensus section Stenophora was sister to the rest of the has emerged with regard to the recognition and/or genus. Using the tree in Fig. 2b, which was mod- circumscription of many of the infrageneric taxa. ified from Fig. 2a and consisted of 27 major clades To resolve this problem, we conducted phyloge- and/or final major subclades including 20 Old netic analyses of 273 samples from 183 species of World sections, we determined the evolution of Dioscorea based on four cpDNA regions, matK, ten selected morphological characters (Noda et rbcL, atpB and trnL–F (Noda et al. 2020). For the al. 2020). The Gillettii–group, Burchellii–group, phylogenetic analyses, 3,754 characters were Tentaculigera–group and Birmanica–group 188 Acta Phytotax. Geobot. Vol. 71
Fig. 1. Habit of species of Dioscorea. a. D. tokoro (staminate); b. D. tentaculigera (staminate); c. D. bulbifera (staminate); d. D. esquirolii (sterile); e. D. velutipes (pistillate); f. D. japonica (staminate). October 2020 Noda & al. — An Infrageneric Classification of Old World Dioscorea 189
Table 1. Data matrix of ten morphological characters in Mesquite of sections and species groups of Dioscorea. Sections and species groups [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] Dioscorea 0 0 0 0 0&1 0 0 0&1 0&1 1&0 NWI (Epipetrum) 1 1 2 0 0 2 0 0 0 4 NWI (expect Epipetrum) 1 1 1 0 0&1 0 0 0 0 1&0 NWII 1 0&1 1 0 0 1 0 0 0 1 Borderea 1 0 3 0 0 2 0 0 0 4 Tamus 1 1 3 1 0 0 0 ? 0 4 Afoborderea 1 1 ? 0 0 0 0 0 0 4 Rhacodophyllum 1 1 ? 0 0 0 0 0 0 0 Perennia 1 1 ? 0 0 0 0 0 0 1 Testudinaria 1 1 0 0 0 0&2 0 0 0 2 Pseudoshannicorea 1 ? 4 0 0 0 0 0 0 3 Opsophyton 1 1 4 0 0 0 0 0 0 1 Lasiophyron 1 1 4 0 1 0 0 0 1 1 NWIII (Apodostemon2) 1 ? ? 0 0 0 0 0 0 0 NWIII (Lasiogyne) 1 1 4(&1) 0 0 0 0 1 0 0 NWIII (Apodostemon1) 1 1 4(&1) 0 0 0 0 0 0 0 NWIII (Rajania) 1 ? ? 2 0 0 0 ? 0 4 Macroura 1 1 4 0 0 0 1 0 0 3 Cardiocarpa 1 1 ? 0 0&1 0 0 1 0 0 Brachyandra 1 1 ? 0 0 0 0 0 0 1 Stenocorea 1 1 ? 0 0 0 0 1 0 0 Combilium 1 1 4 0 0 0 0 0 1 0 Shannicorea 1 1 4 0 0 0 0 0 1 2 Paramecocarpa 1 ? ? 0 0 0 0 0 1 2 Macrocarpaea 1 1 4 0 0 0 0 0 1 3 Pseudostenophora 0 1 ? 0 0 0 0 1 1 0 Enantiophyllum 1 1 4 0 0 1 1 1 0&1 0&2 Characters and character-states. [1] Underground stem rhizome (0), tuber (1); [2] number of pollen aperture monosulcate (0), bisulcate (1); [3] chromosome: x = 10 and diploid (0), x = 9 (1), x = 7 (2), x = 6 (3), polyploid of x = 10 (4); [4] fruit: capsule (0), berry (1), samara (2); [5] leaf: simple (0), compound (1); [6] stem: twining to left (0), twining to right (1) or not twinned (2); [7] phyllotaxis alternate (0), opposite (1); [8] capsule longer than its width (0) or wider than its length (1); [9] stem/leaf indu- mentum absent (0) or present (1); [10] seed wings all around the seed entity (0), basally (1), apically (2), or both basally and apically (3), absence of a wing (4).
(Noda et al. 2020: Figs. 5 and 6) are now replaced and morphological evidence, we propose the rec- with four new sections, Dioscorea sects. Afrobor- ognition of two subgenera, Dioscorea (= D. sect. derea, Perennia, Pseudoshannicorea, and Pseu- Stenophora) and Helmia, as well as the need for a dostenophora (described below). The morpholog- revision of the infrageneric classification of the ical characters we analyzed include not only Old World species in subgenus Helmia (Noda et those used in previous infrageneric classifica- al. 2020). tions (Uline 1897, 1898, Knuth 1924, Burkill In this paper, we present a diagnostic key and 1960, Huber 1998), but also pollen and chromo- taxonomic treatment for the two subgenera and some characters, whose systematic and evolu- the 20 Old World sections, of which 19 belong to tionary implications have been suggested for the subgenus Helmia. Of the 20 Old World sections, past 40 years (Pei et al. 1979, Chin et al. 1985, the following 13 have already been proposed and Schols et al. 2005, Viruel et al. 2010). The ten properly circumscribed, mostly by Huber (1998) characters and distribution of their respective as genera or genus-equivalent sections. They are character states are shown in Table 1 (see also Ta- Borderea, Brachyandra, Combilium, Dioscorea ble 2 in Noda et al. 2020). Based on molecular [= D. sect. Stenophora Uline circumscribed by 190 Acta Phytotax. Geobot. Vol. 71
<50 Dioscorea japonica* <50 <50 D. tabatae 6(1) 7(1)10(0&2) <50 D. japonica <50 D. potaninii 77 D. doryphora 62 52 D. japonica 57 D. polystachya & D. batatas 73 D. polystachya 74 62 76 60 D. polystachya* 61 D. cirrhosa* 8(1) 78 62 Enantiophyllum 53 D. formosana <50 66 76 60 D. matsudae <50 64 D. cirrhosa D. cirrhosa 90 98 64 D. benthamii* 96 D. pseudojaponica 60 67 D. glabra* 78 72 D. fordii 10(0) 89 D. nummularia 87 D. lepcharum 86 D. calcicpla 95 89 91 89 D. alata* 86 89 D. fordii <50 D. oryzetorum D. inoponata 73 Pseudostenophora** 81 D. exalata* 88 98 52 D. brevipetiolata 58 94 D. hamiltonii 100 61 100 D. wallichii* 93 D. aspersa D. kratica 99 D. nummularia 96 67 91 D. elegans 53 51 <50 D. hastifolia ⑪96 D. minutiflora 58 52 D. luzonensis 98 D. decipiens 60 D. lanata 99 96 88 98 D. cotinifolia* 94 89 D. schimperiana* 9 10(2) Shannicorea* D. birmanica 90 D. martini 73 95 D. nitens 68 D. velutipes 67 D. yunnanensis 73 92 80 94 D. subcalva var. submollis* 90 88 86 D. subcalva* 100 ⑩ 95 99 D. pseudonitens* 99 72 86 D. nitens 94 D. velutipes 91 87 89 D. hemsleyi* 88 100 99 D. petelotii* 80 D. preussii 90 ⑨ 81 98 D. esculenta* 73 D. daunaea Paramecocarpa* <50 D. ovinala 88 D. namorokensis 87 74 78 D. soso 67 D. mayottensis 72 D. hombuka 76 D. madecassa 91 D. alatipes 99 <50 D. maciba 10(3) 100 69 D. hexagona 99 D. trichantha 98 D. fandra 83 80 99 D. arcuatinervis 94 D. bemarivensis <50 100 100 D. sansibarensis* 70 <50 D. cordata (Rajania) Macrocarpaea* ⑧<50 100 D. hyalinomarginata (Rajania) 83 100 <50 D. baracoensis (Rajania) OW D. scorpioidea (Rajania) 100 74 D. trifida 98 <50 <50 D. dodecaneura D. stegelmanniana 94 73 83 D. pentaphylla* 76 <50 D. esquirolii <50 D. tomentosa 89 D. cumingii 92 D. scortechinii var. parviflora 62 D. pierrei 99 81 97 64 D. kamoonensis* 90 96 99 86 83 65 D. melanophyma* 100 D. scortechinii 10(0) Combilium* 92 100 D. arachidna 63 100 99 D. dregeana* 93 65 D. cochleariapiculata 84 100 76 100 99 D. dumetorum ⑦ <50 100 100 <50 D. dumetorum* D. hispida* 100 90 100 D. bulbifera* ⑥ <50 82 D. antaly 8(1) 9 94 73 D. mollis 100 100 D. tentaculigera* 92 90 86 D. hemicrypta* (Testudinaria) 92 80 D. strydomiana* (Testudinaria) 100 D. elephantipes (Testudinaria) 99 99 D. sylvatica (Testudinaria) 93 D. brownii Stenocorea* 91 <50 D. burchellii 60 <50 D. mundtii 100 D. mundtii 97 100 89 96 85 D. stipulosa* 86 69 100 ⑤ 87 100 D. buchananii* 99 74 D. multiloba 69 83 D. rupicola 10(1) 100 D. kituiensis (Borderea) 100 D. gillettii (Borderea) 99 84 95 D. communis* (Tamus) 93 74 D. orientalis (Tamus) 93 83 Tamus edulis (Tamus) ④ 81 100 D. chouardii (Borderea) 100 D. pyrenaica (Borderea) 100 D. campos-portoi Brachyandra* 77 100 D. pedalis 100 90 56 D. delicata 94 69 53 D. campestris 91 D. glomerulata 51 59 88 D. ovata 92 D. maianthemoides 96 D. putisensis 8(1) 10(0) D. larecajensis 62 D. cienegensis 64 62 D. coronata 93 96 D. monandra 99 55 D. monadelphya 96 D. lagoa-santa 81 D. subhastata 99 98 D. grandiflora Cardiocapsa 69 ③ 81 96 D. piperifolia 97 D. convolvulacea 99 D. galeottiana 93 D. coriacea 84 D. stenophylla 66 D. juxtlahuacensis 69 65 D. longirhiza 7(1) 10(3) 77 <50 61 D. minima <50 55 D. multinensis 69 D. macvaughii 76 88 D. itatiensis 95 D. perdicum 100 71 <50 D. acanthogene 100 71 D. polygonoides Macroura* D. therezopolensis 66 D. sinuata D. brachybotrya <50 D. laxiflora 59 D. olfersiana 82 D. hassleriana 99 85 D. pohlii 81 D. asperula 10(4) 89 4(2) 73 96 75 D. amazonum 93 D. amaranthoides 79 D. cynanchifolia 92 80 72 D. trisecta 85 67 66 D. marginata <50 D. composita 73 D. leptostachya NWIII(Rajania) 77 69 <50 D. bradei D. sphaeroidea D. pseudomacrocapsa D. multiflora 89 D. besseriana 82 100 95 D. gracilis 97 98 D. modesta 77 91 D. humifusa 10(0) 51 84 D. saxatilis 85 91 D. variifolia 100 ② <50 99 D. aristolochiifolia 64 96 D. fastigiata 100 D. pedicellata 100 100 98 D. biloba* (Epipetrum) 100 D. humilis* (Epipetrum) 63 NWIII(Apodostemon2) 69 62 D. collettii* 85 D. izuensis 89 56 59 D. collettii var. hypoglauca* 73 91 63 89 D. collettii 93 100 89 D. tokoro* 100 D. tenuipes 51 NW 53 72 D. gracillima* 61 71 D. asclepiadea 8(1) 64 D. zentaroana 63 D. caucasica 78 <50 D. deltoidea 94 93 D. spongiosa 58 86 D. futschauensis 86 91 D. futschauensis 87 89 76 83 D. quinquelobata* NWIII(Lasiogyne) 100 10(0) 60 93 99 D. nipponica* 91 76 D. althaeoides 79 85 D. septemloba* 98 92 D. sinoparviflora <50 92 D. zingiberensis <50 D. rockii 99 93 <50 D. membranacea* 72 88 53 D. banzhuana 100 D. simulans 100 ① D. biformifolia 3(4) D. prazeri Stenomeris borneensis NWIII(Apodostemon1) a 5 9 10(1) Lasiophyton* Opsophyton* 10(3) Pseudoshannicorea** 10(2) Testudinaria 10(1) Perennia** 10(0) OW Rhacodophyllum* 10(4) Afroborderea** 4(1) 3(3) 10(4) Tamus* subg. Helmia 6(2) 1 2 Borderea* 3(1) 6(1) 10(1) dioecy, NWII diploid 3(1) 10(0&1) with x =10 NWI (except Epipetrum) NW 3(2) 6(2) 7(2) 10(4) twining stem, orbicule NWI(Epipetrum) subg. Dioscorea 10(0&1) Dioscorea* OW b Stenomeris Fig. 2. a. Phylogenetic tree of Dioscorea (Noda et al. 2020). b. Evolution of morphological characters on tree modified from Fig. 2a. The tree consists of 27 major clades and/or final major subclades, which represent 20 Old World sections and seven New World sections or species groups. ①–⑪ represent 11 major clades. * indicates 13 already proposed and prop- erly circumscribed sections mostly by Huber (1998). ** indicates four new sections (for details see ‘Taxonomy’ in the text). Characters ([1] to [10]) and character-state polarities are as follows. [1]. Underground stem: rhizome (0), tuber (1); [2]. number of pollen apertures: monosulcate (0), bisulcate (1); [3]. chromosome: x = 10 and diploid (0), x = 9 (1), x = 7 (2), x = 6 (3), polyploid of x = 10 (4); [4]. fruit: capsule (0), berry (1), samara (2); [5]. leaf: simple (0), compound (1); [6]. stem: twin- ing to left (0), twining to right (1) not twining (2); [7]. Phyllotaxis: alternate (0), opposite (1); [8]. Capsule: longer than wide (0) wider than long (1); [9]. stem/leaf indumentum: absent (0) present (1); [10]. seed wings: surrounding seed (0), at base (1), at apex (2), at both base and apex (3), wing absent (4). Solid square = apomorphy, open square = homoplasy, cross bar = reversal. Data matrix showing character state distributions are presented in Table 1. NW and OW indicate New World and Old World sections or species groups, respectively. October 2020 Noda & al. — An Infrageneric Classification of Old World Dioscorea 191
*
Lasiophyton
Opsophyton Pseudoshannicorea Enantiophyllum
Testudinaria
Perennia
Rhacodophyllum Afroborderea Tamus
Borderea New World Pseudostenophora
New World
Shannicorea
Paramecocarpa Macrocarpaea Combilium Stenocorea Dioscorea * Brachyandra
Cardiocapsa Macroura New World
Fig. 3. Phylogenetic tree of Dioscorea showing relationships of 20 Old World sections. Strongly supported clades (90–100% TBE support; see Noda et al. 2020) are indicated by thick branches. 192 Acta Phytotax. Geobot. Vol. 71
Burkill (1960)], Lasiophyton, Macrocarpaea, sections, D. sects. Cardiocapsa, Enantiophyllum, Macroura, Opsophyton, Paramecocarpa, and Testudinaria, are emended with broader cir- Rhacodophyllum, Shannicorea, Stenocorea and cumscriptions. Positions and relationships of Tamus. The four sections, Dioscorea sects. Af- those 20 Old World sections are presented on the roborderea, Perennia, Pseudoshannicorea, and tree in Fig. 3. Pseudostenophora, are new. The three remaining
Taxonomy
Dioscorea L., Sp. Pl: 1032 (1753). — Lectotype Merione Salisb., Gen. Pl. Fragm.: 12 (1866). species: Dioscorea villosa L. (McNeill et al. — Type species: Dioscorea villosa L. (cf. Cad- 1987). dick et al. 2002b).
Key to the subgenera of Dioscorea
1a. Underground stem a rhizome; pollen monosulcate ...... I. subg. Dioscorea 1b. Underground stem a tuber; pollen bisulcate ...... II. subg. Helmia
I. Dioscorea subg. Dioscorea type species (hic designatus): Dioscorea gracil- Dioscorea subg. Eudioscorea Pax in Engl., lima Miq. Nat. Pflanzenfam. 2 (5): 134 (1888), nom. invalid. Dioscorea sect. Japonicae R. Knuth in Engl., Pflanzenr. 4 (43): 254 (1924). — Type species: Di- About 35 species are recognized. oscorea asclepiadea Prain & Burkill. Dioscorea sect. Eustenophora R. Knuth in 1. Dioscorea sect. Dioscorea Engl., Pflanzenr. 4 (43): 313 (1924), nom. invalid. Dioscorea sect. Stenophora Uline in Engl. & Prantl, Nat. Pflanzenfam. Nachtr. 2 (5): 84 (1897). Distribution. Temperate Asia to Malesia, — Dioscorea subg. Stenophora (Uline) R. Knuth Caucasus and N America. in Engl., Pflanzenr. 4 (43): 313 (1924). — Lecto- type species (hic designatus): Dioscorea quinqu- Representative species. D. althaeoides, D. as- elobata Thunb., 'quinqueloba'. clepiadea, D. banzhuana, D. biformifolia, D. cau- Dioscorea sect. Macropoda Uline in Engl. & casica, D. collettii, D. deltoidea, D. futschauen- Prantl, Nat. Pflanzenfam. Nachtr. 2 (5): 85 (1897). sis, D. gracillima, D. izuensis, D. membranacea, — Lectotype species (hic designatus): Di- D. nipponica, D. prazeri, D. quinquelobata, D. oscorea villosa L. (cf. Al-Shehbaz & Schubert rockii, D. septemloba, D. simulans, D. sinoparvi- 1989). flora, D. spongiosa, D. tenuipes, D. tokoro (Fig. Dioscorea sect. Orientali-asiaticae R. Knuth 1a), D. villosa (not analyzed here), D. zentaroana in Engl., Pflanzenr. 4 (43): 252 (1924). — Lecto- and D. zingiberensis. October 2020 Noda & al. — An Infrageneric Classification of Old World Dioscorea 193
II. Dioscorea subg. Helmia (Kunth) Benth. in dregeana (Kunth) T. Durand & Schinz.] (Caddick Benth. & Hook. f., Gen. Pl. 3: 743 (1883). — Hel- et al. 2002b). mia Kunth, Enum. Pl. 5: 414 (1850). — Lectotype species: Helmia dregeana Kunth [≡ Dioscorea About 595 species are recognized.
Key to the Old World sections of Dioscorea subgenus Helmia
1a. Seeds wingless all round ...... 2 1b. Seeds winged ...... 4 2a. Fruits baccate ...... sect. Tamus 2b. Fruits capsular ...... 3 3a. Perfect stamens 3, staminodes 3; stem twining to left; capsules ca. 1.5 times as long as wide ..... sect. Afroborderea 3b. Perfect stamens 6; stem not twining; capsules ca. 1.1 times as long as wide ...... sect. Borderea 4a. Stem lignified, woody ...... sect. Testudinaria 4b. Stem not lignified, herbaceous ...... 5 5a. Stem twining to right ...... sect. Enantiophyllum 5b. Stem twining to left ...... 6 6a. Leaves opposite ...... sect. Macroura 6b. Leaves alternate ...... 7 7a. Capsules wider than long ...... 8 7b. Capsules longer than wide ...... 10 8a. Plants totally pubescent ...... sect. Pseudostenophora 8b. Plants totally glabrous ...... 9 9a. Tuber annual (solid tuber only one, connected to empty tubers); bulbils present; exine ornamentation of pollen per- forate ...... sect. Stenocorea 9b. Tuber perennial (solid tubers several, connected to one another); bulbils absent; exine ornamentation of pollen stri- ate ...... sect. Cardiocapsa 10a. Seeds winged all around ...... 11 10b. Seeds winged only at apex and/or base ...... 12 11a. Leaves lobed ...... sect. Rhacodophyllum 11b. Leaves entire or obscurely undulate ...... sect. Combilium 12a. Wing of seeds pointing toward both apex and base of capsule ...... 13 12b. Wing of seeds pointing toward either apex or base of capsule ...... 14 13a. Abaxial surface of leaves woolly-hairy ...... sect. Macrocarpaea 13b. Abaxial surface of leaves glabrous ...... sect. Pseudoshannicorea 14a. Wing of seeds pointing toward capsule apex (Noda et al. 2020: Fig. 6) ...... 15 14b. Wing of seeds pointing toward capsule base (Noda et al. 2020: Fig. 6) ...... 16 15a. Stem prickly; tuber perennial ...... sect. Paramecocarpa 15b. Stem hairy; tuber annual ...... sect. Shannicorea 16a. Leaves compound ...... sect. Lasiophyton 16b. Leaves simple ...... 17 17a. Tuber horizontal or globose; bulbils present; leaves elliptic ...... sect. Opsophyton 17b. Tuber vertical; bulbils absent; leaves lanceolate to ovate ...... 18 18a. Tuber annual (solid tuber only one, connected to empty tubers); stem smooth ...... sect. Brachyandra 18b. Tuber perennial (solid tubers several, connected to one another); stem usually verruculose ...... sect. Perennia
2. Dioscorea sect. Tamus (L.) Noda & M. N. Distribution. Europe to Macaronesia. Tamura, stat. nov. Basionym: Tamus L., Sp. Pl.: 1028 (1753). Representative species. D. communis, D. edu- — Type species: Tamus communis L. [≡ Di- lis and D. orientalis. oscorea communis (L.) Caddick & Wilkin]. 194 Acta Phytotax. Geobot. Vol. 71
3. Dioscorea sect. Borderea (Miégev.) Prain & Representative species. D. brownii, D. ele- Burkill in J. Proc. Asiat. Soc. Bengal 10: 5 (1914). phantipes, D. hemicrypta, D. strydomiana and D. — Borderea Miégev., Bull. Soc. Bot. France 13: sylvatica. 374 (1866). — Dioscorea subg. Borderea (Mié- gev.) Benth. in Benth. & Hook. f., Gen. Pl. 3: 743 7. Dioscorea sect. Perennia Archibald ex Noda (1883). — Type species: Dioscorea pyrenaica & M. N. Tamura, sect. nov. Bubani & Bordère ex Gren. Dioscorea sect. Perennia Archibald in J. S. African Bot. 33: 14 (1967), nom. nud. Distribution. Central Pyrenees. Dioscorea sect. Perennia is similar to D. sect. Brachyan- dra, but differs from it in having a perennial tuber. Representative species. D. chouardii and D. pyrenaica. Type species. Dioscorea mundtii Baker
4. Dioscorea sect. Afroborderea Noda & M. N. Distribution. S Africa. Tamura, sect. nov. Dioscorea sect. Afroborderea is similar to D. sect. Bor- Representative species. D. burchellii, D. derea, but differs from it in having 3 fertile stamens with mundtii and D. stipulosa. 3 sterile staminodes, and stem twining to left. 8. Dioscorea sect. Pseudoshannicorea Noda & Type species. Dioscorea gillettii Milne-Redh. M. N. Tamura, sect. nov. Dioscorea sect. Pseudoshannicorea is similar to D. sect. Distribution. W Africa (S Ethiopia to Kenya). Shannicorea, but differs from it in having the wings of the seeds pointing toward both apex and base of the cap- Representative species. D. gillettii and D. ki- sule. tuiensis. Type species. Dioscorea tentaculigera Prain 5. Dioscorea sect. Rhacodophyllum Uline ex R. & Burkill Knuth in Engl., Pflanzenr. 4 (43): 183 (1924). — Lectotype species (hic designatus): Di- Distribution. China (SW Yunnan), Myanmar oscorea buchananii Benth. and Thailand.
Distribution. S Africa. Representative species. D. tentaculigera (Fig. 1b). Representative species. D. buchananii, D. multiloba and D. rupicola. 9. Dioscorea sect. Opsophyton Uline in Engl. & Prantl, Nat. Pflanzenfam. Nachtr. 2 (5): 84 (1897). 6. Dioscorea sect. Testudinaria (Salisb. ex — Lectotype species: Dioscorea bulbifera L. Burch.) Burkill in J. S. African Bot. 18: 185 (Huber 1998). (1952). — Testudinaria Salisb. ex Burch., Trav. S. Africa. 2: 147 (1824). — Dioscorea subg. Testudi- Distribution. Widespread in the Old World naria (Salisb. ex Burch.) Uline in Bot. Jahrb. (except D. mollis from Brasil). Syst. 25: 157 (1898). — Type species: Dioscorea elephantipes (L'Hér.) Engl. Representative species. D. antaly, D. bul- Dioscorea sect. Eutestudinaria Uline in Bot. bifera (Fig. 1c) and D. mollis. Jahrb. Syst. 25: 157 (1898), nom. invalid. 10. Dioscorea sect. Lasiophyton Uline in Engl. Distribution. S Africa. & Prantl, Nat. Pflanzenfam. Nachtr. 2 (5): 84 October 2020 Noda & al. — An Infrageneric Classification of Old World Dioscorea 195
(1897). — Lectotype species (hic designatus): (1897). — Type species: Dioscorea bemarivensis Dioscorea dumetorum (Kunth) Pax. Jum. & H. Perrier (= D. lucida Scott Elliot, nom. Dioscorea sect. Trieuphorostemon Uline in illeg.). Engl. & Prantl Nat. Pflanzenfam. Nachtr. 2 (5): Dioscorea sect. Madagascarienses R. Knuth 84 (1897). — Type species: Dioscorea pentaphyl- in Engl., Pflanzenr. 4 (43): 70 (1924). — Lecto- la L. type species (hic designatus): Dioscorea arcu- Dioscorea sect. Botryosicyos (Hochst.) Uline atinervis Hochr. in Engl. & Prantl, Nat. Pflanzenfam. Nachtr. 2 (5): 84 (1897). — Botryosicyos Hochst. in Fl. 27, Distribution. Madagascar. Bes. Beil. 3 (1844). — Type species: Botryosicyos pentaphyllus Hochst. (= Dioscorea quartiniana Representative species. D. arcuatinervis and A. Rich.). D. bemarivensis. Dioscorea sect. Illigerastrum Prain & Burkill in Kew Bull. 1933: 241 (1933). — Lectotype spe- 14. Dioscorea sect. Combilium Prain & Burkill cies (hic designatus): Dioscorea dissimulans in J. Proc. Asiat. Soc. Bengal 10: 7 (1914). — Type Prain & Burkill. species: Dioscorea esculenta (Lour.) Burkill (= D. aculeata Roxb., nom. illeg.). Distribution. Widespread in the Old World. Distribution. Malesia to India. Representative species. D. arachidna, D. co- chleariapiculata, D. cumingii, D. dregeana, D. Representative species. D. esculenta. dumetorum, D. esquirolii (Fig. 1d), D. hispida, D. kamoonensis, D. melanophyma, D. pentaphylla, 15. Dioscorea sect. Stenocorea Prain & Burkill D. pierrei, D. scortechinii and D. tomentosa. in J. Proc. Asiat. Soc. Bengal 10: 40 (1914). — Type species: Dioscorea stenomeriflora Prain 11. Dioscorea sect. Macroura Burkill in Blumea, & Burkill. Suppl. 1: 232 (1937). — Type species: Dioscorea sansibarensis Pax. Distribution. China to India.
Distribution. Tropical Africa. Representative species. D. daunaea.
Representative species. D. sansibarensis. 16. Dioscorea sect. Macrocarpaea Uline in Engl. & Prantl, Nat. Pflanzenfam. Nachtr. 2 (5): 12. Dioscorea sect. Brachyandra Uline in Engl. 86 (1897). — Lectotype species (hic designatus): & Prantl, Nat. Pflanzenfam. Nachtr. 2 (5): 83 Dioscorea hylophila Harms. (1897). — Type species: Dioscorea heteropoda Baker. Distribution. Tropical Africa.
Distribution. Madagascar. Representative species. D. preussii.
Representative species. D. alatipes, D. fan- 17. Dioscorea sect. Paramecocarpa Burkill ex dra, D. hexagona, D. hombuka, D. karatana, D. Prain & Burkill in Fl. Gén. Indo-Chine 6: 702 maciba, D. mayottensis, D. namorokensis, D. ovi- (1934). — Type species: Dioscorea petelotii Prain nala, D. soso and D. trichantha. & Burkill. Dioscorea sect. Paramecocarpa Burkill in 13. Dioscorea sect. Cardiocapsa Uline in Engl. Gard. Bull. Straits Settlem. 3: 123 (1924), in nota, & Prantl, Nat. Pflanzenfam. Nachtr. 2 (5): 87 nom. nud. 196 Acta Phytotax. Geobot. Vol. 71
Distribution. Indochina Peninsula. D. benthamii, D. brevipetiolata, D. calcicola, D. cirrhosa, D. cotinifolia, D. decipiens, D. dory- Representative species: D. petelotii. phore, D. elegans, D. exalata, D. fordii, D. formo- sana, D. glabra, D. hamiltonii, D. hastifolia, D. 18. Dioscorea sect. Shannicorea Prain & Burkill inopinata, D. japonica (Fig. 1f), D. kratica, D. la- in J. Proc. Asiat. Soc. Bengal 10: 7 (1914). — Lec- nata, D. lepcharum, D. luzonensis, D. matsudae, totype species (hic designatus): Dioscorea velu- D. minutiflora, D. nummularia, D. oryzetorum, tipes Prain & Burkill. D. polystachya, D. potaninii, D. pseudojaponica, D. schimperiana, D. tabatae and D. wallichii. Distribution. China to SE Asia.
Representative species. D. hemsleyi, D. marti- This study was supported in part by JSPS KAKENHI nii, D. nitens, D. pseudonitens, D. subcalva, D. (Grants-in-Aid for Scientific Research) Grant Number JP16H05763 and JP17K07530. velutipes (Fig. 1e) and D. yunnanensis.
19. Dioscorea sect. Pseudostenophora Noda & References M. N. Tamura, sect. nov. Al-Shehbaz, I. A. & B. G. Schubert. 1989. The Diosco- Dioscorea sect. Pseudostenophora is similar to D. sect. reaceae in the southeastern United States. J. Arnold Dioscorea (=D. sect. Stenophora), but differs from it in Arbor. 70: 57–95. having bisulcate pollen grains. Burkill, I. H. 1960. The organography and the evolution of the Dioscoreaceae, the family of the yams. J. Linn. Type species. Dioscorea birmanica Prain & Soc. (Bot.) 56: 319–412. Burkill. Caddick, L. R., P. J. Rudall, P. Wilkin, T. A. J., Hedderson & M. W. Chase. 2002a. Phylogenetics of Dioscore- ales based on combined analyses of morphological Distribution. China to SE Asia. and molecular data. Bot. J. Linn. Soc. 138: 123–144. Caddick, L. R., P. Wilkin, P. J. Rudall, T. A. J. Hedderson Representative species. D. birmanica. & M. W. Chase. 2002b. Yams reclassified: a recir- cumscription of Dioscoreaceae and Dioscoreales. Taxon 51: 103–114. 20. Dioscorea sect. Enantiophyllum Uline in Chin, H. C., M. C. Chang, P. P. Ling, C. T. Ting & F. P. Engl. & Prantl, Nat. Pflanzenfam. Nachtr. 2 (5): Dou. 1985. A cytotaxonomic study on Chinese Di- 87 (1897). — Lectotype species (hic designatus): oscorea L. — The chromosome numbers and their re- Dioscorea alata L. lation to the origin and evolution of the genus. Acta Dioscorea sect. Asterotricha Uline in Engl. & Phytotax. Sin. 23: 11–18 (in Chinese with English summary). Prantl, Nat. Pflanzenfam. Nachtr. 2 (5): 87 (1897). Couto, R. S., A. C. Martins, M. Bolson, R. C. Lopes, E. C. —Type species: Dioscorea schimperiana Hochst. Smidt & J. M. A. Braga. 2018. Time calibrated tree of Dioscorea sect. Syntepaleia Uline in Engl. & Dioscorea (Dioscoreaceae) indicates four origins of Prantl, Nat. Pflanzenfam. Nachtr. 2 (5): 87 (1897). yams in the Neotropics since the Eocene. Bot. J. Linn. — Lectotype species (hic designatus): Di- Soc. 188: 144–160. Gao, X., Y. P. Zhu, B. C. Wu, Y. M. Zhao, J. Q. Chen & Y. oscorea semperflorens Uline. Y. Hang. 2008. Phylogeny of Dioscorea sect. Ste- Dioscorea sect. Stenophyllidium Uline in nophora based on chloroplast matK, rbcL and trnL-F Engl. & Prantl, Nat. Pflanzenfam. Nachtr. 2 (5): sequences. J. Syst. Evol. 46: 315–321. 87 (1897). — Type species: Dioscorea hastifolia Hsu, K. M., J. L. Tsai, M. Y. Chen, H. M. Ku & S. C. Liu. Nees. 2013. Molecular phylogeny of Dioscorea (Diosco- reaceae) in East and Southeast Asia. Blumea 58: 21– 27. Distribution. Widespread in the Old World. Huber, H. 1998. Dioscoreaceae. In: Kubitzki, K. (ed) The families and genera of vascular plants, vol. III, Flow- Representative species. D. alata, D. aspersa, ering plants Monocotyledons , pp. 216–235. Springer, October 2020 Noda & al. — An Infrageneric Classification of Old World Dioscorea 197
Berlin. Uline, E. B. 1898. Eine monographie der Dioscoreaceen. Knuth, R. 1924. Dioscoreaceae. In: Engler, H. G. A (ed) Bot. Jahrb. Syst. 25: 126–165. Das Pflanzenreich, 87 (IV. 43), pp. 1–387. H. R. En- Viruel, J., F. Forest, O. Paun, M. W. Chase, D. Devey, R. gelmann (J. Cramer), Leipzig. S. Couto, J. Gabriel, P. Segarra-Moragues Catalán & Maurin, O., A. M. Musaya, P. Catalan, E. Z. Shongwe, J. P. Wilkin. 2018. A nuclear Xdh phylogenetic analysis Viruel, P. Wilkin & M. van der Bamk. 2016. Diversi- of yams (Dioscorea: Dioscoreaceae) congruent with fication into novel habitats in the Africa clade of Di- plastid trees reveals a new Neotropical lineage. Bot. J. oscorea (Dioscoreaceae): erect habit and elephant’s Linn. Soc. 187: 232–246. foot tubers. BMC Evol. Biol. 16: 238–255. Viruel, J., J. G. Segarra-Moragues, E. Pérez-Collazos, L. McNeill, J., E. A. Odell, L. L. Consaul & D. S. Katz. 1987. Villar & P. Catalán. 2010. Systematic revision of the American Code and later lectotypifications of Lin- Epipetrum group of Dioscorea (Dioscoreaceae) en- naean generic names dating from 1753: A case study demic to Chile. Syst. Bot. 35: 40–63. of discrepancies. Taxon 36: 350–401. Viruel, J., J. G. Segarra-Moragues, L. Raz, F. Forest, P. Noda, H., J. Yamashita, S. Fuse, R. Pooma, M. Poopath, Wilkin, I. Sanmartın & P. Catalan. 2016. Late Creta- H. Tobe & M. N. Tamura. 2020. A large-scale phylo- ceous–Early Eocene origin of yams (Dioscorea, Di- genetic analysis of Dioscorea (Dioscoreaceae), with oscoreaceae) in the Laurasian Palaearctic and their reference to character evolution and subgeneric rec- subsequent Oligocene–Miocene diversification. J. ognition. Acta Phytotax. Geobot. 71: 103–128. Biogeogr. 43: 750–762. Pei, C., C. T. Ting, H. C. Chin, P. Su, S. Y. Tang & H. C. WCSP. 2019. World checklist of selected plant families. Chang. 1979. A preliminary systematic study of Di- Facilitated by the Royal Botanic Gardens, Kew. oscorea L. sect. Stenophora Uline. Acta Phytotax.
Received December 22, 2019; accepted January 17, 2020
Appendix 1. Literature that we utilized for the aforementioned taxonomy of Dioscorea. Plant names in bold are accepted, those in italics are synonyms. Dioscorea L., Sp. Pl: 1032 (1753); Kunth, Enum. Pl 5: 325 in J. Linn. Soc. Bot. 56: 402 (1960); Huber in Kubitzki, (1850); Benth. in Benth. & Hook f., Gen. Pl. 3: 742 (1883); Fam. Gen. Vasc. Pl. 3: 229 (1998); Ding & Gilbert in Wu Pax in Engl., Nat. Pflanzenfam. 2 (5): 133 (1888); Uline in & Raven, Fl. China 24: 277 (2000); Yamashita & Tamura Engl. & Prantl, Nat. Pflanzenfam. Nachtr. 2 (5): 80 (1897), in Iwatsuki et al., Fl. Japan 4b: 176 (2016). in Bot. Jahrb. Syst. 25: 155 (1898); R. Knuth in Engl., Dioscorea sect. Macropoda Uline in Engl. & Prantl, Pflanzenr. 4 (43): 45 (1924); Prain & Burkill in Fl. Gén. Nat. Pflanzenfam. Nachtr. 2 (5): 85 (1897), in Bot. Jahrb. Indo-Chine 6: 699 (1934); Burkill in Fl. Males. I, 4: 299 Syst. 25: 157 (1898); R. Knuth in Engl., Pflanzenr. 4 (43): (1951), in J. Linn. Soc. Bot. 56: 400 (1960); Huber in Ku- 171 (1924); Huber in Kubitzki, Fam. Gen. Vasc. Pl. 3: 231 bitzki, Fam. Gen. Vasc. Pl 3: 226 (1998); Ding & Gilbert (1998). in Wu & Raven, Fl. China 24: 276 (2000); Caddick et al. in Taxon 51: 108 (2002); Wilkin & Thapyai in Santisuk & Dioscorea subg. Helmia (Kunth) Benth. in Benth. & Larsen, Fl. Thailand 10: 4 (2009); Yamashita & Tamura in Hook. f., Gen. Pl. 3: 743 (1883); Pax in Engl., Nat. Pflan- Iwatsuki et al., Fl. Japan 4b: 171 (2016). zenfam. 2 (5): 133 (1888); Uline in Engl. & Prantl, Nat. Pflanzenfam. Nachtr. 2 (5): 83 (1897), in Bot. Jahrb. Syst. Dioscorea subg. Dioscorea 25: 156 (1898); R. Knuth in Eng., Pflanzenr. 4 (43): 50 Dioscorea subg. Eudioscorea Pax in Engl., Nat. (1924). Pflanzenfam. 2 (5): 134 (1888); Uline in Engl. & Prantl, Nat. Pflanzenfam. Nachtr. 2 (5): 84 (1897), in Bot. Jahrb. Dioscorea sect. Tamus (L.) Noda & M. N. Tamura — Ta- Syst. 25: 157 (1898); R. Knuth in Engl., Pflanzenr. 4 (43): mus L., Sp. Pl.: 1028 (1753); Kunth Enum. Pl. 5: 453 157 (1924), nom. invalid. (1850); Benth. in Benth. & Hook. f., Gen. Pl. 3: 744 (1883); Pax in Engl., Nat. Pflanzenfam. 2 (5): 136 (1888); Uline in Dioscorea sect. Dioscorea Bot. Jahrb. Syst. 25: 157 (1898); R. Knuth in Engl., Pflan- Dioscorea sect. Stenophora Uline in Engl. & Prantl, zenr. 4 (43): 340 (1924); Burkill in J. Linn. Soc. Bot. 56: Nat. Pflanzenfam. Nachtr. 2 (5): 84 (1897), in Bot. Jahrb. 400 (1960); Heywood in Tutin et al., Fl. Europaea 5: 85 Syst. 25: 157 (1898); Prain & Burkill in Fl. Gén. Indo- (1980); Huber in Kubitzki, Fam. Gen. Vasc. Pl. 3: 228 Chine 6: 700 (1934); Burkill in Fl. Males. I, 4: 303 (1951), (1998). 198 Acta Phytotax. Geobot. Vol. 71
Appendix 1. Continued. Dioscorea sect. Borderea (Miégev.) Prain & Burkill in J. in Kubitzki, Fam. Gen. Vasc. Pl. 3: 233 (1998). Proc. Asiat. Soc. Bengal 10: 5 (1914); Burkill in J. Linn. Soc. Bot. 56: 403 (1960). — Borderea Miégev., Bull. Soc. Dioscorea sect. Macroura Burkill in Blumea, Suppl. 1: Bot. France 13: 374 (1866); Pax in Engl., Nat. Pflanzen- 232 (1937); Burkill & H. Perr. in Fl. Madag. 44e Fam.: 4 fam. 2 (5): 133 (1888); Uline in Engl. & Prantl, Nat. Pflan- (1950); Burkill in J. Linn. Soc. Bot. 56: 403 (1960); Huber zenfam. Nachtr. 2 (5): 80 (1897), in Bot. Jahrb. Syst. 25: in Kubitzki, Fam. Gen. Vasc. Pl. 3: 229 (1998). 155 (1898); R. Knuth in Engl., Pflanzenr. 4 (43): 327 (1924); Heywood in Tutin et al., Fl. Europaea 5: 85 Dioscorea sect. Brachyandra Uline in Engl. & Prantl, (1980); Huber in Kubitzki, Fam. Gen. Vasc. Pl. 3: 230 Nat. Pflanzenfam. Nachtr. 2 (5): 83 (1897), in Bot. Jahrb. (1998). Syst. 25: 156 (1898); R. Knuth in Engl., Pflanzenr. 4 (43): 68 (1924); Burkill & H. Perr. in Fl. Madag. 44e Fam.: 35 Dioscorea sect. Rhacodophyllum Uline ex R. Knuth in (1950); Burkill in J. Linn. Soc. Bot. 56: 404 (1960); Huber Engl., Pflanzenr. 4 (43): 183 (1924); von Teichmanet al. in in Kubitzki, Fam. Gen. Vasc. Pl. 3: 232 (1998). Boissiera 24: 219 (1975); Huber in Kubitzki, Fam. Gen. Vasc. Pl. 3: 229 (1998). Dioscorea sect. Cardiocapsa Uline in Engl. & Prantl, Nat. Pflanzenfam. Nachtr. 2 (5): 87 (1897), in Bot. Jahrb. Dioscorea sect. Testudinaria (Salisb. ex Burch.) Burkill Syst. 25: 159 (1898); R. Knuth in Engl., Pflanzenr. 4 (43): in J. S. African Bot. 18: 185 (1952), in J. Linn. Soc. Bot. 311 (1924), 'Cardiocarpa'; Burkill & H. Perr. in Fl. 56: 403 (1960); von Teichman et al. in Boissiera 24: 222 Madag. 44e Fam.: 12 (1950); Burkill in J. Linn. Soc. Bot. (1975). — Testudinaria Salisb. ex Burch., Trav. S. Africa. 56: 403 (1960); Huber in Kubitzki, Fam. Gen. Vasc. Pl. 3: 2: 147 (1824); Kunth Enum. Pl. 5: 440 (1850); Benth. in 230 (1998). Benth. & Hook. f., Gen. Pl. 3: 744 (1883); Pax in Engl., Dioscorea sect. Madagascarienses R. Knuth in Nat. Pflanzenfam. 2 (5): 135 (1888); Huber in Kubitzki, Engl., Pflanzenr. 4 (43): 70 (1924); Burkill & H. Perr. in Fam. Gen. Vasc. Pl. 3: 228 (1998). — Dioscorea subg. Fl. Madag. 44e Fam.: 9 (1950); Burkill in J. Linn. Soc. Testudinaria (Salisb. ex Burch.) Uline in Bot. Jahrb. Syst. Bot. 56: 403 (1960); Huber in Kubitzki, Fam. Gen. Vasc. 25: 157 (1898); R. Knuth in Engl., Pflanzenr. 4 (43): 321 Pl. 3: 230 (1998). (1924). Dioscorea sect. Combilium Prain & Burkill in J. Proc. Dioscorea sect. Perennia Archibald ex Noda & M. N. Asiat. Soc. Bengal 10: 7 (1914); R. Knuth in Engl., Pflan- Tamura zenr. 4 (43): 186 (1924); Prain & Burkill in Fl. Gén. Indo- Dioscorea sect. Perennia Archibald in J. S. African Chine 6: 701 (1934); Burkill & H. Perr. in Fl. Madag. 44e Bot. 33: 14 (1967); von Teichman et al. in Boissiera 24: Fam.: 7 (1950); Burkill in Fl. Males. I, 4: 307 (1951), in J. 222 (1975); Huber in Kubitzki, Fam. Gen. Vasc. Pl. 3: 232 Linn. Soc. Bot. 56: 403 (1960); Huber in Kubitzki, Fam. (1998), nom. nud. Gen. Vasc. Pl. 3: 228 (1998); Ding & Gilbert in Wu & Ra- ven, Fl. China 24: 284 (2000); Yamashita & Tamura in Dioscorea sect. Opsophyton Uline in Engl. & Prantl, Iwatsuki et al., Fl. Japan 4b: 175 (2016). Nat. Pflanzenfam. Nachtr. 2 (5): 84 (1897), in Bot. Jahrb. Syst. 25: 157 (1898); R. Knuth in Engl., Pflanzenr. 4 (43): Dioscorea sect. Stenocorea Prain & Burkill in J. Proc. 85 (1924); Prain & Burkill in Fl. Gén. Indo-Chine 6: 703 Asiat. Soc. Bengal 10: 40 (1914); R. Knuth in Engl., Pflan- (1934); Burkill & H. Perr. in Fl. Madag. 44e Fam.: 24 zenr. 4 (43): 310 (1924); Prain & Burkill in Fl. Gén. Indo- (1950); Burkill in Fl. Males. I, 4: 311 (1951), in J. Linn. Chine 6: 701 (1934); Burkill in Fl. Males. I, 4: 305 (1951), Soc. Bot. 56: 403 (1960); Huber in Kubitzki, Fam. Gen. in J. Linn. Soc. Bot. 56: 403 (1960); Huber in Kubitzki, Vasc. Pl. 3: 233 (1998); Ding & Gilbert in Wu & Raven, Fam. Gen. Vasc. Pl. 3: 230 (1998); Ding & Gilbert in Wu Fl. China 24: 287 (2000); Yamashita & Tamura in Iwat- & Raven, Fl. China 24: 284 (2000). suki et al., Fl. Japan 4b: 175 (2016). Dioscorea sect. Macrocarpaea Uline in Engl. & Prantl, Dioscorea sect. Lasiophyton Uline in Engl. & Prantl, Nat. Pflanzenfam. Nachtr. 2 (5): 86 (1897), in Bot. Jahrb. Nat. Pflanzenfam. Nachtr. 2 (5): 84 (1897), in Bot. Jahrb. Syst. 25: 158 (1898); R. Knuth in Engl., Pflanzenr. 4 (43): Syst. 25: 157 (1898); R. Knuth in Engl., Pflanzenr. 4 (43): 221 (1924); Burkill in J. Linn. Soc. Bot. 56: 403 (1960); 131 (1924); Prain & Burkill in Fl. Gén. Indo-Chine 6: 702 Huber in Kubitzki, Fam. Gen. Vasc. Pl. 3: 229 (1998). (1934); Burkill & H. Perr. in Fl. Madag. 44e Fam.: 20 (1950); Burkill in Fl. Males. I, 4: 313 (1951), in J. Linn. Dioscorea sect. Paramecocarpa Burkill ex Prain & Soc. Bot. 56: 404 (1960); Huber in Kubitzki, Fam. Gen. Burkill in Fl. Gén. Indo-Chine 6: 702 (1934), in Ann. Rep. Vasc. Pl. 3: 233 (1998); Ding & Gilbert in Wu & Raven, Bot. Gard. Calcutta 14: 93 (1936); Burkill in Fl. Males. I, Fl. China 24: 290 (2000). 4: 309 (1951), in J. Linn. Soc. Bot. 56: 403 (1960); Huber Dioscorea sect. Trieuphorostemon Uline in Engl. & in Kubitzki, Fam. Gen. Vasc. Pl. 3: 229 (1998). Prantl Nat. Pflanzenfam. Nachtr. 2 (5): 84 (1897), in Bot. Dioscorea sect. Paramecocarpa Burkill in Gard. Jahrb. Syst. 25: 157 (1898); R. Knuth in Engl., Pflanzenr. Bull. Straits Settlem. 3: 123 (1924), in nota, R. Knuth in 4 (43): 137 (1924). Engl., Pflanzenr. 4 (43): 355 (1924), nom. nud. Dioscorea sect. Botryosicyos (Hochst.) Uline in Engl. & Prantl, Nat. Pflanzenfam. Nachtr. 2 (5): 84 (1897), Dioscorea sect. Shannicorea Prain & Burkill in J. Proc. in Bot. Jahrb. Syst. 25: 157 (1898); R. Knuth in Engl., Asiat. Soc. Bengal 10: 7 (1914); R. Knuth in Engl., Pflan- Pflanzenr. 4 (43): 150 (1924); Huber in Kubitzki, Fam. zenr. 4 (43): 317 (1924); Prain & Burkill in Fl. Gén. Indo- Gen. Vasc. Pl. 3: 233 (1998); Ding & Gilbert in Wu & Ra- Chine 6: 702 (1934); Burkill in J. Linn. Soc. Bot. 56: 404 ven, Fl. China 24: 287 (2000); Yamashita & Tamura in (1960); Huber in Kubitzki, Fam. Gen. Vasc. Pl. 3: 229 Iwatsuki et al., Fl. Japan 4b: 174 (2016). (1998); Ding & Gilbert in Wu & Raven, Fl. China 24: 285 Dioscorea sect. Illigerastrum Prain & Burkill in Kew (2000). Bull. 1933: 241 (1933), in Fl. Gén. Indo-Chine 6: 701 (1934); Burkill in J. Linn. Soc. Bot. 56: 404 (1960); Huber Dioscorea sect. Enantiophyllum Uline in Engl. & Prantl, October 2020 Noda & al. — An Infrageneric Classification of Old World Dioscorea 199
Appendix 1. Continued. Nat. Pflanzenfam. Nachtr. 2 (5): 87 (1897), in Bot. Jahrb. 255 (1924); Burkill in J. Linn. Soc. Bot. 56: 403 Syst. 25: 159 (1898); R. Knuth in Engl., Pflanzenr. 4 (43): (1960); Huber in Kubitzki, Fam. Gen. Vasc. Pl 3: 231 257 (1924); Prain & Burkill in Fl. Gén. Indo-Chine 6: 703 (1998). (1934); Burkill & H. Perr. in Fl. Madag. 44e Fam.: 69 Dioscorea sect. Syntepaleia Uline in Engl. & Prantl, (1950); Burkill in Fl. Males. I, 4: 320 (1951), in J. Linn. Nat. Pflanzenfam. Nachtr. 2 (5): 87 (1897), in Bot. Jahrb. Soc. Bot. 56: 403 (1960); Huber in Kubitzki, Fam. Gen. Syst. 25: 159 (1898); R. Knuth in Engl., Pflanzenr. 4 (43): Vasc. Pl. 3: 231 (1998); Ding & Gilbert in Wu & Raven, 307 (1924). Fl. China 24: 291 (2000); Yamashita & Tamura in Iwat- Dioscorea sect. Stenophyllidium Uline in Engl. & suki et al., Fl. Japan 4b: 172 (2016). Prantl, Nat. Pflanzenfam. Nachtr. 2 (5): 87 (1897), in Bot. Dioscorea sect. Asterotricha Uline in Engl. & Prantl, Jahrb. Syst. 25: 159 (1898); R. Knuth in Engl., Pflanzenr. Nat. Pflanzenfam. Nachtr. 2 (5): 87 (1897), in Bot. Jahrb. 4 (43): 309 (1924). Syst. 25: 159 (1898); R. Knuth in Engl., Pflanzenr. 4 (43):