王庆华 郑笑傲 蒋 勇 贾 渝*

（1. 中国科学院植物研究所，系统与进化植物学国家重点实验室，北京 100093；2. 四川贡嘎山国家级自然保护区管理局，康定 626000）

1 Introduction

Hedw.was recently divided into three genera，namelyF. Lara，Garilleti& Goffinet，andPlášek，Sawicki & Ochyra，according to the molecular evidences，whereas in this study we still use its concept. The Chinesehas just been studied most recently，although the species they confirmed are somewhat different，they both found two centers of diversity for the genus，one is Tianshan and Altai Mountains in Xinjiang，the other is Hengduan Mountains region. Gongga Mountain is the highest peak of Hengduan Mountains，located at south of Kangding，Sichuan Province. However，the bryophyte diversity in this area has been lack of comprehensive investigation for a long time. Recently，we are engaged in this work and found many new populations of，two of which belong toLewinsky.

is an endemic species from Bhutan. Since its first publication in 1992，it has been known only from the type locality. Although Lewinsky’s original description is very detailed and has a beautiful line drawing and a SEM（scanning electron microscope）photo，it is easy to be ignored because it is never mentioned again later. Therefore，this new record from China has deepened our understanding ofmorphologically and geographically.

2 Results

J. Hattori Bot. Lab. 72：23. f. 11. 1992. Type：BHUTAN. Bumtang Chu，side valley 2 km N of Byakar Dzong，on，alt. 2 800 m，10 June 1979，.（holotype，E00011762！）

Description：green above，brown to black below，0.7-1.4 cm tall.present at stem base.usually branched.strongly flexuose to moderately crisped when dry，2.6-3.7 mm long；lanceolate，unistratose；acuminate；strong，ending shortly below the apex.oblong or quadrate，（5.9-17.3）μm×（3.6-9.2）μm，moderately to strongly thick-walled，almost smooth；elongate-rectangular，rectangular to quadrate，（13.2-86.7）μm×（2.7-9.7）μm，with moderately thickened walls，smooth.

Autoicous.longer than vegetative leaves，3.8-4.7 mm long.sparsely hairy or naked.slightly to fully emergent，cylindrical，eight light furrows along at least half the entire length，rarely smooth，not constricted when dry and empty.short，abruptly narrowed into seta.uniform.superficial，in the central and lower，rarely upper part of urn.double.not seen.16，usually united into 8 pairs，lanceolate，densely and finely papillose，often reflexed when dry.16，linear the upper half，united the lower half，biseriate，yellowish or hyaline，finely papillose.andnot seen.spherical，unicellular，finely papillose，19-36 μm in diameter.

3 Discussions

is an easily distinguishable species，due to its flexuose to crisped leaves，immersed slightly to fully emergent non-constricted capsules，endostome segments with remarkable high membrane and urn-located stomata（Fig.1）. Among them，the strongly flexuose to moderately crisped leaves are relatively rare in，but easier to remind one of the related genus.However，the leaf bases inare wider and the basal margins have more or less hyaline cells.More importantly，the endostome segments with very high basal membrane are so special that we can’t decide whether it belongs toorat first glance. The overview of peristome provided by Lewinskyagrees well with ours（Fig.2e），but the linear upper half of the endostome segments in her SEM image seems to have fallen off，at least partially，which may lead to the fact that she described eight rather than 16 segments.The configuration of endostome segments is an indispensable criterion for the species classification of，and thus its morphological accuracy is important. The spore size from Gongga Mountains is slightly smaller than that of the type material（Fig.1-2）.

图1 Orthotrichum tortifolium 模式的形态a.植株体；b～d.孢蒴干时状态；e～g.叶片；h～i.雌苞叶；j.孢蒴外壁（深灰色圆点代表气孔）；k.基鞘；l.气孔；m.孢子；n.蒴齿；所有特征取自模式标本（E）Fig.1 Morphology of type specimen of Orthotrichum tortifoliuma.Plants；b-d.Capsules when dry；e-g.Leaves；h-i.Perichaetial leaves；j.Exothecial wall with gray dots representing stomata；k.Vaginula；l.Stoma；m.Spores；n.Peristome；All from holotype in E

contains two lineages，one is phaneroporous species（），the other is cryptoporous species（s.tr.）.belongs to the former. In，strongly flexuose to moderately crisped leaves are rare as mentioned above，and even within phaneroporous species，there are only two except，i.e.Lewinsky from China andHook. f. & Wilson from Oceania.However，the capsules in these two species are long exserted and constricted when dry，and further inits endostome segments are linear-lanceolate and only united at the bases，its stomata are located at the neck，while inits endostome segments are wide-lanceolate without high basal membrane.There are some endostome segments with basal membrane in，which are mainly in cryptoporous species. But these endostome segments are only united at the bases，namely less than half the height，even no more than four cells high，such as the phaneroporous species ofErdağ，Kürschner & Parolly from Turkey，andF. Lara，Garilleti，Draper & Mazimpaka from Spain. Moreover，further differs fromin its erect to flexuose leaves with hyaline hair points and smaller spores（15-20 μm），whileis distinguished in its erect-appressed leaves，immersed capsules and eight linear endostome segments. The differences ofhave been mentioned above.

图2 Orthotrichum tortifolium 新居群的形态a.植株体；b.带孢蒴的枝条；c～d.孢蒴干时状态；e.蒴口；f.基鞘；g～j.叶片；k.孢蒴外壁（深灰色圆点代表气孔）；l.气孔；m.孢子；n.蒴齿；所有特征取自王庆华2545，除了m来自王庆华2555（PE）Fig.2 Morphology of new collection of Orthotrichum tortifoliuma.Plants；b.A branch with capsule；c-d.Capsules when dry；e.Capsule mouth；f.Vaginula；g-j.Leaves；k.Exothecial wall，with gray dots representing stomata；l.Stoma；m.Spores；n.Peristome；All from specimen Q H Wang 2545 except m from Q H.Wang 2555（PE）

图3 野外的Orthotrichum tortifoliuma.生境；b～c.居群Fig.3 Orthotrichum tortifolium in fielda.Habitat；b-c.Populations

grow onat 2 800 m altitude as described by Lewinsky，and our new collections are on shrub branches at 2 235 m above sea level（Fig.3）.

Key toand its closely related species

1.Leaves erect to slightly flexuose when dry ……………………………………………………………………………………… 2

1.Leaves strongly flexuose to moderately crisped when dry ……………………………………………………………………… 3

2.Leaves erect-appressed when dry，without hyaline awn；capsules immersed；calyptra more or less hairy …………

2.Leaves erect to slightly flexuose when dry，with hyaline awn；capsules immersed to subexserted；calyptra naked …

3.Capsules slightly to fully emergent，not constricted when dry；endostome segments united the lower half（about ten cells high）…………………………………………………………………………………………………………………………

3.Capsules long exserted，smooth or constricted when dry；endostome segments free or united at the bases（no more than four cells high） …………………………………………………………………………………………………………………………… 4

4.Endostome segments 8，wide，triangular；stomata present in the upper half of the capsules …………………

4.Endostome segments 16，narrow，linear-lanceolate；stomata present on the capsule neck only ………………

Additional specimens examined（all in PE）：

：CHINA. Sichuan：Jiulong Co.，roadside，29°12′58.23″N，102°0′47.78″E，alt.2 235 m，on shrub branch，15 April 2021，.

We thank the curator at E for the loan of type specimen.