Premna fulva Craib (1911: 442)

Tan, Yunhong & Li, Bo, 2014, Taxonomic studies on the genus Premna (Lamiaceae) in China-I: the identities of P. fulva and P. tapintzeana, Phytotaxa 173 (3), pp. 207-216 : 209-212

Premna fulva Craib (1911: 442) . Figs. 1A–B and 3A–F .

Type:— THAILAND. Chiang Mai: DoiSuthep , alt. 700 m, 10 April 1910, A.F.G.Kerr 1085 (holotype K!; isotypes BM! [sheet no. 000019563], K!, TCD) .

Premna crassa Handel-Mazzetti (1921: 230) , syn. nov. Type:— CHINA. Kweitschou (Guizhou): Huangguoshu , alt. 580–950 m, 20 June 1917, Handel-Mazzetti 10361 (holotype WU! [sheet no.WU0060380]; isotypes A! [sheet no. 00095359], W! [sheet no. 1924-0003117]).

Climbing shrubs, up to 6 m tall. Branchlets, petioles, leaf blades and inflorescences densely covered with long, spreading, golden-brown hairs when young, subglabrescent when mature. Branches reddish brown, grooved; branchlets spreading, terete, with an interpetiolar ridge between petioles. Leaves opposite, usually unequal in pairs, crushed leaves with disagreeable smell; Petioles robust, (1.5–)3.5–7.5(–9.5) cm; leaf blades mostly ovate to subrounded, rarely oblong-ovate, ovate-lanceolate to elliptic, (3.5–)5–9(–13.5) × (3–)4.5–8.5(–10.3) cm, papery, abaxially whitish with golden viens, becoming yellowish brown when dry, densely tomentose, adaxially dark green but becoming reddish brown when dry, densely yellow villous especially on veins, base mostly subcordate to cordate, or subrounded to rounded, margin dentate below middle or serrate, apex acuminate to obtuse, or rarely subrounded to emarginate; veins 4–5(–6) pairs, 3-veined near base. Inflorescences corymbose cyme, flat-topped, 2.5–6(–8.5) × (3.5–)4.5–9.5(–11) cm; branches 5 or 6 pairs, spreading; bracts linear to rarely linear-lanceolate, densely pubescent. Calyx campanulate, 2.2–3 mm long, lobes 5, sub-equal, apex obtuse or rounded, externally pubescent and glandular, fruiting calyx ca. 5 mm in diameter, lobes obscure. Corolla greenish white, densely villous in throat, outside puberulent to subglabrous, 2-lipped, lower lip 3-lobed, sub-equal, ovate-orbicular, apex rounded to obtuse, middle lobe with a yellow patch near throat, upper lip rounded to emarginate, tube longer than calyx. Stamens as long as upper lip, included or slightly exserted; anthers whitish or yellowish. Ovary globose, ca. 1 mm in diameter, apically sparsely pubescent; style as long as stamens, apex acute. Fruit green when young, reddish purple to bluish black when mature, globose, 4.5–5.5 mm in diameter, endocarp tuberculate; seeds four and equally developed when mature.

Illustrations:— P’ei & Chen (1982: 98, Fig. 49); Chen & Gilbert (1994: 53, Fig. 53, 1–5); Ho (1999: 822, Fig. 7309).

Distribution and habitat:— This species is mainly distributed in northern (Chiang Mai, Chiang Rai, Phayao, Lampoon, Lampang, Phrae and Kamphaeng Phet), northeastern (Loei) and eastern (Chaiyaphum) Thailand ( Leeratiwong et al. 2009), northern (Louangphrabang) and central (Bolikhamxai) Laos ( Newman et al. 2007), northern (Lang Son, HàSƠnBình, Lang Biang and Hà Nam Ninh) Vietnam ( Ho1999), and southwestern China (Yunnan, Guangxi and Guizhou)( Fig. 5 ). Premna fulva is found in dense tropical rainforests or monsoon forests ( Fig. 3A, B ), or subtropical evergreen forests, but was also rarely found in secondary and mixed deciduous forests.

Phenology:— Flowering from late March to May; fruiting from April to late July.

Notes:— In Premna fulva leaf blade varies mostly ovate to ovate-lanceolate to subrounded, leaf base subcordate to cordate ( Figs. 3C, D ). It can be easily distinguished from other Premna species in having dense golden-brown spreading hairs on branchlets, petioles and peduncles ( Figs. 3C–F ), and adaxially reddish brown leaves when dry ( Figs. 1A, B ). As the type specimen of P. crassa bears such characters, the species is reduced to P. fulva as synonym.

Premna crassa was first recognized by P’ei (1932) in The Verbenaceae of China. In the monograph, P’ei (1932) cited Handel-Mazzetti’s original description of the name, and noted that “the species differs from its allies by its ovate to nearly orbicular leaves which are densely pubescent beneath”. Though he saw one of the isotypes held at A (sheet no. 00095359), the conspecific status of the P. crassa with P. fulva was not pointed out because he did not record P. fulva in his monograph at that time. A note as "= P. fulva Craib " is written on the sheet by an anonymous scientist, however, this recognition may not has been evident to the subsequent Chinese taxonomists, and hence P. crassa was as separate species in Flora Reipublicae Popularis Sinicae (P’ei & Chen 1982) and Flora of China ( Chen & Gilbert 1994).

Additional specimens examined:— CHINA: Guangxi: Longjin County, 13 June 1957 , S.Q.Chen 11862 (IBK sheet no. 00058223, KUN sheet no. 198492); Longlin County, Wuchong Town, C.F.Liang & D.L.Wu 32584 (IBK sheet no. 00058227); Longzhou County , 26 May 1935 , S.P.Ko 55136 (PE sheet no. 01276469); Nonggang Nature Reserve , 2 May 1980 , J.Y.Liang 12034 (IBK sheet no. 00058220); Pingguo County, Chaiguang Town , 2 June 1957 , Y.K.Li 01366 (IBK sheet no. 00058231); Tian'e County, Ronglong Town , 15 May 1957 , Z.Huang 43257 (IBK sheet no. 00058229, KUN sheet no. 198491, PE sheet no. 01276455); Tianyang County, Namo District , 21April 1964 , Z.Z.Chen 54032 (IBK sheet no. 00058232); Xilin County, Nabi Village , 28 June 1936 , R.X.Liang 67874 (IBK sheet no. 00058226, PE sheet no. 01276456); Guizhou: Luodian County, Yangli , 29 May 1965 , anonymous 711 (KUN sheet no. 198489); Luodian County, Fengting , 12 April 1959 , South Guizhou Exp. 470 (KUN sheet no. 198490); Wangmo County, near Hongshui River , April 1964 , C.Y.Wu 5 (KUN sheet no. 198488); No location data, 12 June 1929 , Q.Q.Zhong 1444 (PE sheet no. 01276454); Yunnan: Funing County, 25 May 1976 , L.Y.Xiao 11207 (HITBC sheet no. 046715); Funing County, Jinba to Xi'ai , 14 June 1964 , S.Z.Wang 962 (KUN sheets no. 198474, 198483); Hekou County, the Fourth District , 24 May 1953 , K.H.Cai 1172 (KUN sheets no. 198466, 198467); Jingdong County, Ganlanba , 16 May 1953 , anonymous 31 (KUN sheet no. 301005); Jingdong County, Mangu , 16 April 1957 , Sino-Russia Exp. 9270 (KUN sheets no. 198472, 198482); Jinghong City, Jinuo Town , 2 April 1981 , J.Y.Cui 19565 (HITBC sheet no. 046672); Jinping County, Mengla District , 11 November 1956 , Sino-Russia Exp. 502 (PE sheet no. 01276462); Jinping County, Laomenghe , 20 May 1974 , Lüchun Exp. 968 (KUN sheets no. 198461, 198462, 198463, 198475); Mengla County, Bubang , 31 May 1982 , Yunnan Exp. 31498 (HITBC sheet no. 046496); Mengla County, Menglun Town , 13 June 1973 , G.D.Tao 7072 (HITBC sheet no. 046333); Mengla County, Mengyuan Town , 24 April 1964 , Y.H.Li 4890 (HITBC sheet no. 046493); Yuanjiang County, near Qingshuihe River , 8 May 1985 , G.D.Tao 38073 (HITBC sheet no. 046703); LAOS: No location data, 30 April 1993 , G.D.Tao 930008 (HITBC sheet no. 059362); THAILAND: Chiang Mai, Muang, Ru-See Cave area , 21 June 1989 , J.F.Maxwell 89529 (MO sheets no. 3945623, 3945625, 3946070).

Figures

FIGURE 1. Type specimens of some Premna taxa.A. isotype of P. crassa (W sheet no. 1924-0003117); B. isotype of P. fulva (BM sheet no. 000019563); C. holotype of P. tapintzeana (P sheet no. 00689530); D. isotype of P. crassa var. yuii (PE sheet no. 01276420). With the permission from the Natural History Museum (BM), the Muséum National d’Histoire Naturelle (P), the Herbarium of Institute of Botany, CAS (PE), and the Naturhistorisches Museum Wien (W).

FIGURE 3. Premna fulva. A. climbing habit (arrowed) and habitat; B. climbing branch on a tree; C. branchlet and abaxial surface of leaves, showing dense golden-brown spreading hairs; D. adaxial surface of leaves; E. an inflorescence; F. a fruitescence. Photographs A–D from Xishuangbanna Tropical Botanical Garden, Yunnan Province, China by B. Li, and E, F from Menghai County, Yunnan Province, China by Y. H. Tan.

FIGURE 5. Distribution map of Premna fulva (green stars) and Premna tapintzeana (orange circles).