Volume 14 NOVON Number 2 2004 Novelties and Notes on Miscellaneous Asian Brassicaceae Ihsan A. Al-Shehbaz Missouri Botanical Garden, P.O. Box 299, St. Louis, Missouri 63166-0299, U.S.A. [email protected] ABSTRACT. Draba bartholomewii (Brassicaceae), a 1964; Ball & Dudley, 1993; Zhou et al., 2001; Ap- new species from Qinghai, China, is described and pel & Al-Shehbaz, 2003), a few others (e.g., Re- illustrated. The monotypic genera Coelonema and benskaya, 1994; Czerepanov, 1995) maintain both Nesocrambe are reduced to the synonymy of Draba genera. As indicated by Zhou et al. (2001), the and Hemicrambe, respectively. The new combina- characters used to distinguish Ptilotrichum from tions Alyssum dahuricum, Draba draboides, Hemi- Alyssum (e.g., white vs. yellow ¯owers, edentate vs. crambe socotrana, Lepidium coronopus, and Pe- dentate ®laments, and 1-seeded vs. 2- or 3-seeded gaeophyton purii are proposed. locules) are unreliable and found within Alyssum Key words: Alyssum, Asia, Brassicaceae, Coe- excluding Ptilotrichum. Therefore, these alleged lonema, Dilophia, Draba, Hemicrambe, Lepidium, generic boundaries are arti®cial, and the two gen- Nesocrambe, Pegaeophyton, Ptilotrichum. era should be united. All except one of the species Delimitation of genera of Brassicaceae (Crucifer- originally described in Ptilotrichum have names in ae) is a well-known problem, and 125 of the 337 Alyssum. The following new combination is needed. genera recognized by Appel and Al-Shehbaz (2003) are monotypic, with about an additional 100 con- Alyssum dahuricum (Peschkova) Al-Shehbaz, taining two to four species (oligotypic). Molecular comb. nov. Basionym: Ptilotrichum dahuricum studies (see review by Koch et al., 2003) have Peschkova, Novosti Sist. Vyssh. Rast. 15: 230. clearly demonstrated that the vast majority of 1979. TYPE: Russia. Chita: Onon River sys- monotypic genera are indistinguishable from and tem, mountain at Bukukun River, near Buku- nested within larger genera. Upon a critical re-eval- kunskij, 18 July 1913, V. Smirnov 1986 (ho- uation of morphology, two monotypic genera, Coe- lotype, LE). lonema Maximowicz and Nesocrambe A. G. Miller, are reduced herein to synonymy of other genera Alyssum dahuricum is easily distinguished at an- well established on the basis of morphological and thesis from the closely related A. tenuifolium Ste- molecular grounds (Koch & Al-Shehbaz, 2002; phan ex Willdenow by having stramineous stems Koch et al., 2003; Warwick & Black, 1997; GoÂmez- and by lacking the basal and lowermost cauline Campo, 1999). leaves. By contrast, A. tenuifolium has purplish or The present paper deals with the description of greenish stems and persistent basal rosette and a new species of Draba, as well as nomenclatural cauline leaves. adjustments in the genera Alyssum L., Draba L., Hemicrambe Webb, Lepidium L., and Pegaeophyton DRABA VERSUS COELONEMA Hayek & Handel-Mazzetti. The monotypic Coelonema was recognized in ALYSSUM VERSUS PTILOTRICHUM various Chinese ¯oras (e.g., Zhou et al., 2001) as Although most authors place Ptilotrichum C. A. endemic and was said to differ from Draba solely Meyer in the synonymy of Alyssum (e.g., Dudley, by including stoloniferous perennials with ¯attened NOVON 14: 153±157. 2004. 154 Novon bases of staminal ®laments. Draba was said to con- branched primarily at or near base, pubescent with sist of annuals, biennials, or perennials with slen- subsessile stellate trichomes rarely mixed with sim- der or slightly ¯attened staminal ®laments. A crit- ple ones, rarely glabrous distally. Basal leaves with- ical examination at LE of the type of C. draboides ered by anthesis; cauline leaves 2 to 6(to 10), ses- Maximowicz, as well as numerous other species of sile, not auriculate; leaf blade ovate to elliptic, 1± Asian Draba, reveals that these alleged differences 3.5 3 0.4±1.5 cm, abaxially pubescent with are insigni®cant because several species of Draba subsessile or short-stalked, 4-rayed, stellate tri- (e.g., D. sibirica (Pallas) Thellung) are typically sto- chomes with simple rays, adaxially with subsetose loniferous, and the ®lament bases vary in this com- simple or long-stalked forked trichomes sometimes plex genus of ca. 350 species from slender to dis- mixed with fewer, smaller, 4-rayed stellate ones, tinctly ¯attened. Therefore, the conclusion reached base cuneate, margin 3- to 5-toothed on each side, by Appel and Al-Shehbaz (2003) in uniting Coe- apex acute. Racemes 8- to 20-¯owered, ebracteate, lonema with Draba is justi®ed, and the following elongated in fruit; rachis straight; fruiting pedicels new combination is needed to accommodate C. dra- 5±15 mm long, horizontal, straight, pubescent all boides in Draba. around, or rarely glabrescent. Sepals oblong, 1±1.3 3 0.6±0.8 mm, erect, abaxially pilose with stellate Draba draboides (Maximowicz) Al-Shehbaz, trichomes, base of lateral pair not saccate, margin comb. nov. Basionym: Coelonema draboides membranous; petals yellow, spatulate, 1.2±1.6 3 Maximowicz, Bull. Acad. Imp. Sci. Saint-PeÂ- 0.5±0.6 mm, apex retuse, obscurely clawed at base; tersbourg 26: 424. 1880. TYPE: China. [Gan- ®laments 0.8±1 mm; anthers ovate, 0.1±0.2 mm; su]: ``Terra Tangutorum. Jugum S a ¯. Tetung ovules 14 to 20 per ovary. Fruit oblong, 8±10(±12) ad declivitates denudates mintium rarius, 30 3 (2.5±)3±3.5 mm, often horizontal, latiseptate, not April±12 May 1873,'' N. M. Prezewalski 14 twisted; valves sparsely puberulent with simple and (holotype, LE). subsessile forked trichomes, rarely glabrescent, ob- scurely veined, base and apex acute; style obsolete, DRABA rarely to 0.1 mm; seeds brown, ovate, 1±1.3 3 0.7± During a visit to LE in 2002, I examined the 0.9 mm. Flowering and fruiting in August. four syntypes of Draba eriopoda Turczaninow, a species widely distributed in Bhutan, China, India, The new species is named after Bruce Barthol- Mongolia, Nepal, and Russia. It became immedi- omew, one of the collectors of the type collection. ately evident that the treatment of D. eriopoda in Draba bartholomewii is easily distinguished from Zhou et al. (2001) represented two distinct species, D. eriopoda by having decumbent stems, horizontal of which one is described below as new. fruiting pedicels pubescent all around or rarely gla- brous, pilose sepals with stellate trichomes, small Draba bartholomewii Al-Shehbaz, sp. nov. petals 1.2±1.6 3 0.5±0.6 mm, oblong, often hori- TYPE: China. Qinghai: Dari (Darlag) Xian, zontal fruits (2.5±)3±3.5 mm wide, and fruit valves just N of Manzhang, along Manzhang He, betw. puberulent with simple and subsessile forked tri- Dari & Banma (Baima), at base of valley sides chomes. By contrast, D. eriopoda has erect stems, in loose soil, 4000 m, 338179510N, divaricate-ascending fruiting pedicels often gla- 1008259550E, 12 Aug. 1993, Ho Tingnung, brous adaxially and pubescent abaxially, pilose se- Bruce Bartholomew & Michael G. Gilbert 1185 pals with simple trichomes, larger petals 2±3(±3.5) (holotype, MO; isotypes, BM, CAS, E, GH, 3 (0.5±)0.8±1 mm, erect or ascending, ovate or HNWP, PE). Figure 1. ovate-elliptic fruits 1.5±2.5 mm wide, and glabrous fruit valves. Herba annua. Caules decumbentes, ad basim ramosi, pilis stellatis praediti. Folia basalia nulla; folia caulina 2± Draba bartholomewii is also related to D. alticola 6(±10), sessilia, nonauriculata, ovata vel elliptica, 1±3.5 Komarov (Afghanistan, China, Kyrgyzstan, Tajikis- 3 0.4±1.5 cm, subtus pilis subsessilibus stellatis 4-radia- tan), which it resembles in ¯ower size and fruit tis praedita, supra pilis subsetosis simplicibus et stipitato- shape. However, the latter has rosulate basal furcatis praedita. Racemi 8±20-¯ori, rhachidibus rectis. Pedicelli fructiferi horizontales, 5±15 mm longi. Petala leaves, lea¯ess stems, a ¯exuous rachis in fruiting ¯ava, spathulata, 1.2±1.6 3 0.5±0.6 mm. Ovarium 14± racemes, pilose sepals with simple and forked tri- 20-ovulatum. Fructus oblongi, 8±10(±12) 3 (2.5±)3±3.5 chomes, glabrous fruits 1±2 mm wide, and seeds mm, compressi, pilis simplicibus et subsessilibus furcatis 0.4±0.5 mm long. Draba bartholomewii lacks the praediti. Semina 1±1.3 3 0.7±0.9 mm. basal leaf rosette and has 2 to 6(to 10) cauline Herbs annual, 5±25 cm tall; stems decumbent, leaves, a straight rachis in fruiting racemes, pilose Volume 14, Number 2 Al-Shehbaz 155 2004 Asian Brassicaceae Figure 1. Draba bartholomewii Al-Shehbaz. ÐA. Plant. ÐB. Trichomes of abaxial leaf surface. ÐC. Trichomes of adaxial leaf surface. ÐD. Petal. Scales: A 5 1 cm; B, C 5 0.2 mm; D 5 0.5 mm. Drawn by Al-Shehbaz from the holotype, Ho, Bartholomew & Gilbert 1185 (MO). 156 Novon sepals with stellate trichomes, puberulent fruits known. Several other genera of the tribe Brassiceae (2.5±)3±3.5 mm wide, and seeds 0.7±0.9 mm long. (e.g., Conicya Porta & Rigor ex Roy, Vella L.) show fruit diversity far greater than in Hemicrambe in- Paratypes. CHINA. Qinghai: Nangqen Xian, Xiao- long Gou, W of Nangqen on road to Domba, 328179N, cluding Nesocrambe (Leadlay & Heywood, 1990; 968169E, T. N. Ho, B. Bartholomew, M. Watson & M. G. Warwick & Al-Shehbaz, 1998). Gilbert 2822 (CAS, HNWP, MO); Tungjen Xian, T. P. Miller et al. (2002: 66) stated that ``the perennial Wang 6186 (PE). Sichuan: Haitzeshan, H. Smith 11598 habit is relatively uncommon in the Brassicaceae.'' (MO, TI, UPS). However, Al-Shehbaz (1984: 349) indicated that ``more than 62 percent [of the family] are peren- HEMICRAMBE VERSUS NESOCRAMBE nials'' and only about 5% are typically woody. Hemicrambe consists of two species, of which one, H. fruticulosa Webb, is endemic to Morocco KEY TO THE SPECIES OF HEMICRAMBE and the other, H. fruticosa (C. C. Townsend) GoÂmez- 1a. Leaves crenate-dentate; ¯owers white; Soqotra Campo, is endemic to the island Soqotra (Yemen).