Helonias Linnaeus (1753: 342)

Tanaka, Noriyuki, 2019, Taxonomy, evolution and phylogeography of the genus Helonias (Melanthiaceae) revisited, Phytotaxa 390 (1), pp. 448-450 : 448-450

Helonias Linnaeus (1753: 342) , p.p., excl. Plukenet & Morison; 1754: 159. Type:― Helonias bullata L.

≡ Abalum Adanson (1763: 47 , 511, ‘Abalon’), p.p., excl. Ephemerum .

= Hexonix Rafinesque (1837 , as ‘1836’: 13), nom. rejic. vs. Heloniopsis Gray (1859) (nom. cons.). ≡ Kozola Rafinesque (1837 , as ‘1836’: 25), nom. rejic. vs. Heloniopsis Gray (1859) (nom. cons.). Basionym of types:― Scilla japonica Thunb.

= Sugerokia Miquel (1866: 24 ; 1867a: 88; 1867b: 144). Type:― Sugerokia japonica Miq.

= Heloniopsis Gray (1859: 416) , nom. cons. Type: H. pauciflora A.Gray.

= Ypsilandra Franchet (1887 – 1888: 93, t. 17; 1888: 131, t. 17). Type: Y. thibetica Franch.

Japanese name:―Shôjôbakama zoku ( Tanaka 1998a: 114).

Species included:―12; Helonias alpina , H. breviscapa , H. bullata , H. jinpingensis , H. kawanoi , H. koreana , H. leucantha , H. orientalis , H. parviflora , H. thibetica , H. umbellata , H. yunnanensis .

Description:―Herbs glabrous, evergreen, polycarpic, hemicryptophytic, perennial. Rhizome cylindrical, sometimes nodose, vertical or ascending, closely subannulate with numerous scars, sometimes branched. Roots filiform, usually to 2 mm in diam., ramose, white, rarely pale orangish or pinkish brown (in sicco), often contractile. Leaves hysteranthous, sometimes proteranthous, many, basal, rosulate at apex of rhizome, usually persistent for 1 or 2 years, spatulate or narrowly oblanceolate, gradually tapering to petiole-like base, margins entire or minutely undulate, apex mucronulate or apiculate, more or less chartaceous (thin to somewhat thick or firm), dull to glossy adaxially, veins parallel, converging near apex, rarely adventitiously producing plantlet (ramet) at apex. Flowering stem arising from center of basal rosette, erect or ascending, longitudinally ribbed, elongating with progression of anthesis, withering around May to June in vernal species, fistulose, bracteate; bracts (scale-like leaves) on peduncle 4–17(–24) (excl. basal ones), subulate, narrowly deltoid, (narrowly) lanceolate or narrowly oblong, apex acute or acuminate, (sub)membranous or herbaceous, sparser and smaller upward; inflorescence racemose, sub-umbellate or umbellate; pedicels terete, ribbed, ebracteate, rarely bracteate, ascending in fruit. Flowers spirally (in raceme) or subverticillately (in umbel) arranged, 1–many, actinomorphic, obconic, crateriform or sometimes campanulate, hermaphroditic, odorous or sometimes odorless, entomophilous, (nearly) adichogamous (homogamous) or dichogamous-protogynous; floral parts persistent after anthesis; flowers in raceme often erect (distal flowers), horizontal (middle ones) or reflexed (proximal ones), sometimes secund and pendulous at mid anthesis; flowers in subumbels and umbels often nodding at mid anthesis; flowers nodding toward end of anthesis. Tepals 6, in 2 whorls of 3, homomorphic, narrowly elliptic, oblong, oblanceolate or spatulate, apex rounded to acute, usually white, pink, purplish or sometimes bluish, turning green after anthesis, veins 3–7(–9), adaxially nearly flat or slightly to pronouncedly canaliculate toward base; proximal submarginal portions often raised (or ridged), sometimes winged (lamellate) inward, wings (lamellae) connate to wings of adjoining tepals, also adnate to opposite filaments forming a tubular nectary; abaxial basal portion usually slightly to markedly gibbous (directed downward); adaxial base secreting nectar, nectary nearly flat, saccate or tubular. Stamens 6, in 2 whorls; filaments subulate or filiform, sometimes complanate toward base, free or adnate basally to proximal submarginal wings of opposing tepals; inner filaments sometimes adnate basally to base of ovary; anthers ovoid, narrowly ovoid or hippocrepiform, unilocular or bilocular (usually) with rudimentary apical confluence between thecae, often purplish, positioned above or below stigmas; pollen usually whitish. Pistil 1, carpels 3; ovary syncarpous, superior, trilocular, adjoining locules dorsally connate partly along central axis (ventral suture), apex emarginate; styles 3, nearly free to base or connate into a single column; column distally trifurcate or simple; ventral surface of distal free part of style or of top of columnar style stigmatic; stigma trisected to trilobed, discoid, capitate or depressed capitate, sometimes slightly trigonous, papillulate; ovules several to numerous per locule, biseriate to multiseriate on central axile placentae, subglobose or oblong at anthesis, anatropous, elongating after fertilization. Capsules antrorse, (broadly) obpyramidal, trifid or tripartite, apex depressed in center or sometimes (sub)truncate; lobes divergent, protruding subdistally, ovoid-subconic or subpyriform, apex rounded, ascending to nearly horizontal; loculicidal, trivalvate; valves cordiform, straw-colored. Seeds many, ascending, fusiform or linear-fusiform, often subfalcate, proximally linear-caudate, distally caudate to acicular; testa white or pale brownish, scarious, soft; body of seed brownish, narrowly oblong-fusiform, situated on one side in middle inside testa.

Distribution:―Eastern North America; eastern Asia ( Bhutan, China, India, Japan, Korea, Myanmar, Nepal, Russia (S Sakhalin), Taiwan, Vietnam) ( Fig. 31 ).

Flowering:―March–May, to July at higher elevations and latitudes; sometimes also August–October or late December–March.

Fruit ripening:―May–June, later at higher elevations and latitudes; rarely November–December or even later.

Habitat:―Open or shaded moist situations, such as swamps, meadows, banks along streams, forests and forest margins from cool temperate to subtropical regions.

Remarks:― Helonias makes up the tribe Heloniadeae with Chamaelirium . It consists of two sections, H. sect. Helonias and H. sect. Heloniopsis ( Table 3). Their diagnostic characteristics are given in Table 4.

Identification key to the sections of Helonias

1.

Figures

FIGURE 31. Geographic ranges of two sections Helonias and Heloniopsis. Ancestral plants of Helonias are presumed to have been in northern high latitudes approximate area of which is encircled with broken line.They are supposed to have been separated into two groups, and eventually one group reached eastern N. America and the other eastern Asia as consequence of their southward migrations (A). ① Sect. Helonias. ②–④ Sect. Heloniopsis. ② Subsect. Ypsilandra. ③ Subsect. Heloniopsis ser. Umbellatae. ④ Subsect. Heloniopsis ser. Heloniopsis. For historical aspect of range extension, see also Figs. 32, 33 and text (Part III).