NOVON 10: 346-348. 2000.
Ihsan A. Al-Shehbaz
Missouri Botanical Garden, P.O. Box 299, St. Louis, Missouri 63166-0299, U.S.A.
Piroche Plants, Inc., 20542 McNeil Road, Pitt Meadows, B.C., Canada V3Y 1Z1
Abstract. The Himalayan (Tibet and adjacent Kashmir) endemic Eurycarpus is recognized, and the characters separating its two species from Christolea, Desideria, and Parrya are discussed. The new combination E. marinellii is proposed, and Christolea longmucoensis is reduced to synonymy of E. marinellii.
In establishing the genus Eurycarpus, Botschantsev (1955) separated it from what was then the invalidly published genus Ermania Chamisso by the biseriate instead of uniseriate seeds, broadly lanceolate instead of linear fruits, entire instead of dentate leaves, and leafless instead of leafy scapes. However, he probably compared only the type species of both genera because most of these alleged differences do not hold if one compares Eurycarpus with the ten species that Botschantsev recognized in Ermania. Eight of the ten species of Ermania are presently assigned to Desideria Pampanini, and the remaining two, including the type of Ermania, belong to the earlier published Melanidion E. L. Greene. For a discussion on the invalidity of Ermania and the generic limits of Desideria and Melanidion, see Al-Shehbaz (2000).
Although the type species of Eurycarpus was originally described in Parrya R. Brown, the two genera are unrelated. Eurycarpus has at least some of the trichomes forked, nonsaccate lateral sepals, terete replums, wingless seeds, and entire stigmas, and it lacks the multicellular glands. By contrast, Parrya has exclusively simple trichomes or the plants are glabrous, strongly saccate lateral sepals, flattened replums, winged seeds, prominently 2-lobed stigmas with decurrent, connivent lobes, and often multicellular glands.
Desideria differs from Eurycarpus by having dentate, often palmately veined leaves, prominently veined valves with well-developed marginal veins, linear to linear-lanceolate fruits rectangular in cross section, valve apices persistently united with replum, obsolete styles, and 2-lobed stigmas. Eurycarpus has entire, pinnately veined leaves, obscurely veined valves without marginal veins, oblong, elliptic, ovate-oblong, or ovate-lanceolate fruits narrowly elliptic in cross section, valve apices readily free from the replum at dehiscence, well-defined subconical styles, and minute, entire stigmas.
Jafri (1955) adopted a very broad generic concept of Christolea that included species presently assigned to six genera (Al-Shehbaz, 2000). He transferred Parrya lanuginosa J. D. Hooker & Thomson to Christolea, a species that Botschantsev (1955) designated as the type of Eurycarpus. Jafri’s account was followed rather closely by An (1987) and Kuan (1985). Eurycarpus is readily distinguished from Christolea by having well-defined rosettes, entire basal leaves, leafless stems, stalked-forked trichomes mixed with simple ones, biseriate seeds, obtuse anthers, basally dilated staminal filaments, slightly elongated infructescences, and obscurely veined valves. Christolea lacks the basal leaves and rosettes, and it has dentate leaves, leafy stems, exclusively simple trichomes, uniseriate seeds, apiculate anthers, basally slender staminal filaments, considerably elongated infructescences, and prominently veined valves. In our opinion, these differences are significant, and they clearly support the recognition of Eurycarpus as a genus distinct from Christolea.
Eurycarpus Botschantsev, Bot. Mater. Gerb. Bot. Inst. Komarova Akad. Nauk S.S.S.R. 17: 172. 1955. TYPE: Eurycarpus lanuginosus (J. D. Hooker & Thomson) Botschantsev.
Herbs perennial, woolly to pilose; caudex slender, few branched. Trichomes simple mixed with stalked 1- to 3-forked ones. Stems erect, simple from rosette. Basal leaves petiolate, rosulate, simple, entire. Stem leaves absent. Racemes several to many flowered, ebracteate, corymbose, elongated slightly in fruit. Fruiting pedicels slender, divaricate. Sepals oblong, deciduous, base of inner pair not saccate, margin membranous. Petals purple; blade spatulate, apex obtuse; claw subequaling sepals. Stamens 6, tetradynamous; filaments dilated at base; anthers oblong, not apiculate at apex. Nectar glands 1, confluent and subtending bases of all stamens; median nectaries present. Ovules 8 to 20 per ovary. Fruit dehiscent silicles, oblong, elliptic, ovate-oblong, or ovate-lanceolate, strongly latiseptate, subsessile; valves obscurely veined, glabrous, smooth; replum rounded, visible; septum complete or reduced to a rim, membranous, translucent; style to 0.5 mm long, subconical; stigma capitate, entire, minute. Seeds biseriate, wingless, oblong, plump or slightly flattened; seed coat minutely reticulate, not mucilaginous when wetted; cotyledons incumbent or accumbent.
Two species: endemic to China (Tibet) and adjacent Kashmir.
Key to the Species of Eurycarpus
1a. Leaves lanuginose; fruits oblong-ovate to ovate-lanceolate; septum reduced to a rim; cotyledons accumbent…1. E. lanuginosus
1b. Leaves pilose; fruits elliptic to oblong, rarely ovate-elliptic; septum complete; cotyledons incumbent…2. E. marinellii
1. Eurycarpus lanuginosus (J. D. Hooker & Thomson) Botschantsev, Bot. Mater. Gerb. Bot. Inst. Komarova Akad. Nauk S.S.S.R. 17: 172. 1955. Parrya lanuginosa J. D. Hooker & Thomson, J. Linn. Soc., Bot. 5: 136. 1861. Christolea lanuginosa (J. D. Hooker & Thomson) Ovczinnikov, Sovetsk. Bot. 1941(1 & 2): 151. 1941. Ermania lanuginosa (J. D. Hooker & Thomson) O. E. Schulz, Repert. Sp. Nov. Regni Veg. 28: 185. 1933. Christolea lanuginosa (J. D. Hooker & Thomson) Jafri, Notes Roy. Bot. Gard. Edinburgh 22: 52. 1955. TYPE: China. Tibet [Xizang]: Lanjar, 17,500 ft., R. Strachey & J. E. Winterbottom 7 (holotype, K; isotypes, BM, GH, K).
Draba lanjarica (as laujarica) O. E. Schulz, Repert. Sp. Nov. Regni Veg. 33: 109. 1935. TYPE: same as that of Parrya lanuginosa (holotype, BM).
Herbs 3--5 cm tall; caudex slender, few branched. Trichomes simple, to 1 mm long, mixed with distinctly stalked 1- to 3-forked ones. Stems densely villous. Basal leaves rosulate, fleshy; petiole 2--7 mm long, persistent, becoming papery; leaf blade suborbicular to spatulate to oblong-obovate, 5--0 ´ 2--6 mm, sublanate with forked trichomes, base cuneate, margin entire, apex obtuse to rounded. Stem leaves absent. Racemes 8- to 15-flowered, ebracteate. Fruiting pedicels divaricate, straight, 4--7 mm long, densely villous. Sepals obong, 2--2.5 ´ 1--1.5 mm, pilose. Petals spatulate, ca. 5 ´ 2.5 mm, apex obtuse; claw ca. 2 mm long. Filaments of median stamens ca. 3 mm long, those of lateral stamens ca. 2 mm long; anthers oblong, ca. 0.6 mm long. Ovules ca. 8 per ovary. Fruit oblong-ovate to ovate-lanceolate, 1.5--2.7 cm ´ 6--10 mm, strongly flattened; valves glabrous, smooth, with obscure midvein and marginal veins, obtuse at base, acute at apex; septum perforate, reduced to a rim; style subconical, 0.2--0.4 mm long; stigma minute, entire. Seeds biseriate, narrowly oblong, flattened, 2--2.5 ´ 1--1.3 mm; cotyledons accumbent.
Slopes; 5100--5300 m. China (Xizang).
Schulz (1935) overlooked the fact that his Draba lanjarica is based on the same type collection as Parrya lanuginosa, a species that he (Schulz, 1933) transferred earlier to the invalidly published Ermania. It is interesting to note that Schulz (1936) placed the same species in two genera of two different tribes. He placed Draba in the tribe Drabeae and Ermania in the tribe Arabideae, and he separated these tribes solely on the basis of having silicles in the Drabeae and siliques in the Arabideae. However, all students of the Brassicaceae readily admit that this distinction in fruit morphology is entirely artificial.
Jafri’s (1955) new combination Christolea lanuginosa is invalid because it was proposed earlier by Ovczinnikov (1941). Jafri (1973) suggested that Eurycarpus lanuginosus (as Christolea) is probably conspecific with C. pumila (Kurz) Jafri and Ermania koelzii O. E. Schulz. That the last two species are conspecific is correct, but as indicated by Al-Shehbaz (2000), they both belong to Desideria pumila (Kurz) Al-Shehbaz, a species clearly unrelated to E. lanuginosus.
Other specimens examined. CHINA. Xizang: Zhada Xian, Northwest Institute of Biology Xizang Expedition 3916 (HNWP).
2. Eurycarpus marinellii (Pampanini) Al-Shehbaz & G. Yang, comb. nov. Basionym: Braya marinellii Pampanini, Bull. Soc. Bot. Ital. 1915: 29. 1915. TYPE: [Kashmir.] Karakorum, 5200 m, 27 June 1914, G. Danielli & O. Marinelli s.n. (holotype, FI).
Christolea longmucoensis Y. H. Wu & Z. X. An, Acta Phytotax. Sin. 32: 579. 1994. Syn. nov. TYPE: China. Xizang: Rutog, Longmu Co, 5380 m, 2 Sep. 1987, Karakorum-Kunlun Expedition 1302 (holotype, HNWP, listed originally as NWBI; isotypes, KUN, PE).
Herbs 3--10 cm tall, pilose; caudex slender, few branched. Trichomes simple, to 1 mm long, mixed with distinctly stalked 1-forked ones. Stems pilose. Basal leaves rosulate, subfleshy; petiole (1--)3--10(--14) mm long, persistent, becoming papery; leaf blade spatulate to oblanceolate, rarely obovate, (2--)3--12(--15) ´ (1--)2--8 mm, pilose with simple and forked stalked trichomes, base cuneate, margin entire, apex obtuse to rounded. Stem leaves absent. Racemes (5 to)10- to 22-flowered, ebracteate. Fruiting pedicels divaricate, straight, 4--8(--10) mm long, pilose. Sepals oblong, 2.2--3 ´ 1--1.5 mm, sparsely pilose. Petals purplish, spatulate, 5--6 ´ 2--2.5 mm, apex obtuse; claw ca. 2 mm long. Filaments of median stamens 2.5--3.5 mm long, those of lateral stamens 1.5--2.5 mm long; anthers oblong, 0.5--0.6 mm long. Ovules 12 to 20 per ovary. Fruit elliptic to oblong, rarely ovate-elliptic, (0.7--)1--1.7(--2) cm ´ (4--)5--7 mm, strongly flattened; valves often purplish, glabrous, smooth, with obscure midvein and marginal veins, subacute at both ends; septum complete; style subconical, 0.2--0.5 mm long; stigma minute, entire. Seeds biseriate, narrowly oblong, not flattened, 2--2.5 ´ 0.8--0.9 mm; cotyledons incumbent.
Alpine areas; 5300--5700 m. China (Xizang), Kashmir.
In his account of Braya Sternberg & Hoppe, Schulz (1924) excluded B. marinellii Pampanini and did not assign it to another genus. Three years later, he (Schulz, 1927) transferred the species to Draba L. It appears that he never examined the type of this species because he (Schulz, 1933) cited two of the collections above, Pike 832 and Thorold 34, as Ermania lanuginosa, whereas Jafri (1973) cited them as Christolea lanuginosa. Evidently, Schulz and Jafri failed to distinguish Eurycarpus marinellii from E. lanuginosus. The latter is readily distinguished by having woolly leaves, oblong-ovate to ovate-lanceolate fruits, perforated septum reduced to a rim, and accumbent cotyledons. Eurycarpus marinellii has pilose leaves, elliptic to oblong or rarely ovate-elliptic fruits, complete septum, and incumbent cotyledons.
The original description and illustration of Christolea longmucoensis (Wu & An, 1994) include several inaccuracies. The leaf trichomes were illustrated and described as stellate and forked. An examination of the type collection and the others cited above reveals that the leaves have simple and once-forked trichomes. The fruit valve was shown to be with a prominent midvein when in fact it is obscurely veined. Although the cotyledons were correctly illustrated as incumbent, they were described as accumbent. Finally, these authors cited only the type collection, which has no flowers. The description of the sepals as 5--6 mm long is also inaccurate. Wu and An (1994) compared Christolea longmucoensis with C. stewartii, but the latter species belongs to the unrelated Desideria (Al-Shehbaz, 2000).
Other specimens examined. CHINA. Xizang: Rutog, Guliya, Li Bosheng & Zheng Du 10975 (PE); Longmucuo Xian, Qinghai-Xizang Team 13616 (MO, PE); Ritu Xian, Duoma, Qinghai-Xizang Team 76-9060 (KUN); E of Horpa Tsu, Pike 832 (K); without locality, Thorold 34 (K).
Acknowledgments. We are grateful to Zhu Guanghua and Song Hong for their help in the translation of Chinese herbarium labels and to Tatyana Shulkina for help with the Russian literature. We thank the directors and curators of the herbaria cited in this paper.
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