Botanica Pacifica. A journal of plant science and conservation. 2019. 8(2): 85–106 DOI: 10.17581/bp.2019.08208 A review of Lejeuneaceae (Marchantiophyta) in the Russian Far East Vadim­A.­Bakalin Vadim­A.­Bakalin ABSTRACT e-mail:­[email protected] The Russian Far East is on the northern edge of the Lejeuneaceae distribution in Pa­cific­Asia­and­the­majority­of ­taxa­known­here­are­restricted­to­the­southern­ Botanical­Garden-Institute­FEB­RAS­ most ­flank­of ­the­region.­Eleven­species­are­confirmed­for­the­Russian­Far­East:­ Vladivostok,­Russia 1 – Acrolejeunea, 1 – Cheilolejeunea, 4 – Lejeunea, 4 – Cololejeunea and 1 – Microlejeunea.­ All ­of ­them­are­reviewed­in­the­present­account,­with­data­on­distribution­within­ the ­Rus­sian­Far­East,­morphological­descriptions­and­figures­based­on­materials­ col­lected ­in­the­Far­East.­In­addition,­identification­keys­to­genera­and­species­are­ pro­vided. Manuscript­received:­25.07.2019 Keywords: Lejeuneaceae, Acrolejeunea, Cheilolejeunea, Cololejeunea, Lejeunea, Microlejeunea, Review­completed:­30.09.2019 the­Russian­Far­East,­East­Asia,­North-East­Asia,­taxonomy,­distribution Accepted­for­publication:­17.10.2019 Published­online:­31.10.2019 РЕЗЮМЕ Бакалин В.А. Обзор семейства Lejeuneaceae на российском Даль- нем Востоке. Представители­ Lejeuneaceae­ обычны­ только­ в­ южной­ ча­ сти ­ российского­ Дальнего­ Востока,­ севернее­ встречается­ единственный­ вид­ –­ Lejeunea alaskana. ­ Всего­ на­ Дальнем­ Востоке­ выявлено­ 11­ видов:­ 1­ –­ Acrolejeunea, 1 – Cheilolejeunea, 4 – Lejeunea, 4 – Cololejeunea­и­1­–­Microlejeunea.е­Вс ­ они ­обсуждаются­в­рамках­настоящей­статьи,­описывающей­их­распростра­ нение,­экологию­и­морфологию­по­образцам­с­российского­Дальнего­Вос­ тока.­Приводятся­иллюстрации­всех­известных­в­регионе­таксонов­и­ключи­ для­определения­родов­и­видов­семейства.. Ключевые слова: Lejeuneaceae, Acrolejeunea, Cheilolejeunea, Cololejeunea, Lejeunea, Microle­ jeunea,­российский­Дальний­Восток,­Восточная­Азия,­таксономия,­распространение Lejeuneaceae­are­the­largest­family­among­the­hepatics­ pos­sible, ­with­the­exception­of ­Nipponolejeunea­ (Jubulaceae)­ acounting­74­accepted­genera­(Zhu­et­al.­2019)­and­ca­1300­ which, ­however,­has­ciliate­leaf­margins­–­a­feature­very­rare­ recognized­species.­Lejeuneaceae­are­characterized­by­ter­mi- in ­ Lejeuneaceae­ worldwide.­ Lejeuneaceae­ did­ not­ at­trac­ted­ nal-lateral­ branching­ (Lejeunea­ rtype,­ rare ­ Frullania­ type,­ in- special ­attention­of ­hepaticologists­in­the­Russian­Far­East.­ nova­tions­usually­of ­the­Radula­ type,­the­presence­of ­a­single­ The ­early­record­of ­Acrolejeunea sandvicensis­ (under­Brachio lejeu­ archegonium­in­each­gynoecium­(Frey­&­Stech­2009,­Grad- nea) ­was­comprehensively­discussed­by­Zerov­(1965),­some­ stein. ­2013) ­The­leaves­consist­of ­three­parts:­a­large­dorsal,­ others ­were­only­listed­(e.g.­Horikawa­1940).­Well­known­in­ in­cubously­oriented­and­inserted­lobe,­a­ventral­smaller­lobe,­ Russia, ­Schljakov’s­manual­(1982)­for­the­hepatics­of ­the­nor- called, ­lobule ­that­is­connected­to­the­lobe,­and­a­stylus­that­ thern­USSR­only­included­Lejeunea cavifolia­ (Ehrh.)­Lindb.­(a­ is ­commonly­vestigial­or­absent.­As­commented­by­Frey­&­ taxon ­absent­in­the­Russian­Far­East­as­well­as­in­the­whole­ Stech ­(2009:­96),­“more­than­75%­of ­the­liverworts­of ­tro- of ­the­western­amphi-Pacific).­Within­the­last­de­cades­se­ve- pical ­lowland­forests­and­almost­all­epiphylls­belong­to­Le­jeu- ral ­new­records­of ­this­family­were­published.­Gam­ba­ryan­ neaceae”. ­The­extraordinary­speciation­in­this­group­is­pro- (1992) ­listed­four­taxa­of ­the­family,­with­L. cavifolia in cor­ bab­ly ­ connected­ with­ the­ Cretaceous­ and­ post-Cretaceous­ rect­ly ­identified­(specimens­belong­to­L. japonica). ­Potemkin­ ex­plo­sion­ of ­ Angiosperms­ that­ provides­ new­ ecological­ (2003) ­recorded­Cololejeunea japonica­ for­the­first­time­in­Rus- niches ­in­tropical­forests­(Wilson­et­al.­2007).­The­highest­ sia.­ Bakalin­ (2007a,­ 2009)­ reviewed­ Cololejeunea in Russian di­ver­sity ­(still­poorly­understood)­occurs­in­humid­tropical­ Asia ­ (later­ one­ more­ taxon­ was­ found­ in­ the­ Rus­sian­ Far­ fo­rests, ­with­modern­centers­of ­speciation­in­Southeastern­ East)­ and­ Cheilolejeunea­ in­ the­ Russian­ Far­ East.­ Ba­ka­lin­ &­ Asia­and­Northern­South­America­(Frey­&­Stech­2009).­ Bo­ro­vi­chev ­(2014)­and­Bakalin­et­al.­(2012)­re­cor­ded­Lejeunea Although ­the­amphi-Pacific­Asian­region­houses­a­high­ neelgherriana and L. alaskana­ as­ new­ for­ Rus­sia.­ Some­ taxa­ num­ber­of ­Lejeuneaceae­taxa­(more­than­500­species),­the­ were ­ earlier­ reported­ without­ descriptions­ for­ the­ Russian­ Rus­sian ­ Far­ East­ has­ a­ very­ limited­ number­ of ­ recorded­ Far ­East­(e.g.­Microlejeunea punctiformis, under Lejeunea ulicina spe­cies,­and­all­of ­them­are­restricted­to­the­southern­flank­ (Tay­lor) ­Gottsche,­Lindenb.­&­Nees­in­Bakalin­2007b).­More- of a ­the­are ­(with­one­exception­for­Lejeunea alaskana).­Due­ over,­ many­ new­ distributional­ data­ were­ collected­ within­ to ­their­peculiar­appearance­among­other­Russian­Far­East­ last ­ several­ years.­ The­ latter­ circumstance,­ as­ well­ as­ the­ liver­worts, ­confusion­with­other­families­seems­to­be­hardly­ difficulties­in­identification­of ­‘lejeuneaceous’­materials­from­ ©Botanical Garden-Institute FEB RAS. 2019 85 Bakalin the ­Russian­Far­East­in­the­absence­of ­keys­have­initiated­the­ bran­ching­ predominantly­ of ­ Frullania­ type­ (branches­ of ­ present ­work.­It­is­worth­mentioning­that­the­prominent­pa- Lejeunea­type­are­rare),­leaf ­lobule­3–5-toothed,­underleaves­ undivided­.............................................................­Acrolejeunea per ­describing­Japanese­Lejeuneaceae­by­Mizutani­(1961)­can­ bedo ­use ­t ­identify­almost­all­Lejeuneaceae­in­the­Russian­Far­ 1.­Plants­pale­green­to­bright­green­and­whitish,­rarely­yel- low­ish, ­never­brownish­or­rusty-brown,­with­less­than­6–8­ East ­although­it­is­difficult­to­use­due­to­enormously­high­ longitudinal­outer­cell­rows­in­the­stem­cross­section,­bran- di­ver­sity ­of ­the­family­in­Japan­that­makes­the­identification­ ching of Lejeunea­, type ­leaf­lobule­2-toothed,­underleaves­ keys ­re­latively­difficult.­The­main­goals­of ­the­present­account­ bilobed­or­absent­......................................................................­2 wereo ­t ­provide:­1)­new­data­on­distribution­and­ecology­of ­ 2. ­Plants­minute,­underleaves­absent,­stylus­(sometimes­ves- Lejeu­neaceae­in­the­Russian­Far­East,­2)­identification­keys­to­ ti­gial)­regularly­present­although­sometimes­easily­caducous­ ...............................................................................­Cololejeunea all ­taxa­known­in­the­Russian­Far­East­and­3)­morphological­ des­criptions­and­figures­based­on­available­material­from­the­ 2.­ Plants­ minute­ to­ moderate­ in­ size,­ regular­ underleaves­ pre­sent,­stylus­absent­or­early­and­easily­caducous­..............­3 Rus­sian ­Far­East.­The­present­work­continues­the­liverwort­ 3.­Oil­bodies­(1–)2–4­per­cell,­brownish,­nearly­filling­cell­lu- re­visions­for­the­Russian­Far­East­(Bakalin­2016,­2018,­2019;­ men,­the­second­tooth­of ­the­leaf ­lobule­far­larger­than­the­ Bakalin­&­Klimova­2019,­Borovichev­&­Bakalin­2016,­Bo­ro- first, ­one ­leaves­imbricate­...............................­Cheilolejeunea vi­chevt ­e ­al.­2014,­2015,­Mamontov­et­al.­2015,­etc.)­toward­ 3.­Oil­bodies­numerous­or­5–10­per­cell­(if ­fewer­–­never­ to ­the­preparation­of ­Liverwort­flora­of ­the­Russian­Far­East­ fil­ling ­cell-lumen­and­leaves­distant),­the­second­tooth­of ­ that­we­plan­to­publish­in­the­next­couple­of ­years. the­leaf ­lobule­smaller­than­the­first­one­or­absent,­leaves­ imb­ri­cate­to­distant­..................................................................­4 MATERIAL AND METHODS 4. ­Plants­very­small,­less­than­0.5­mm­in­width,­leaves­distant,­ The ­background­for­the­present­work­was­the­liverwort­ lobule­only­slightly­smaller­than­lobe­............­Microlejeunea spe­ci­mens ­collected­in­the­Russian­Far­East­by­the­author­ 4. ­Plants­larger,­wider­than­0.7­mm,­leaves­mostly­imbricate,­ wi­thin ­the­past­15­years.­The­results­on­taxonomic­diversity­ or­at­least­contiguous,­lobule­far­smaller­than­lobe­(less­1/4­ were ­preliminary­(as­it­was­possible­at­that­time)­summarized­ of ­the­lobe­size)­..........................................................­Lejeunea in­dist­ribution­dot­maps­by­Bakalin­(2010).­ Acrolejeunea­ (Spruce)­ Schiffn.,­ Hepat.­ (Engl.-Prantl):­ 128,­ In ­total­over­300­specimens­of ­Lejeuneaceae­were­col­lec- 1893= ­( ­Trocholejeunea­ Schiffn.­Ann.­Bryol.­5:­160.­1932;­Bra­ ted.­Aside­afore­men­tio­ned­material­the­herbarium­specimens­ chio lejeunea­ (Spruce)­Schiffn.­Hepat.­(Engl.-Prantl):­128,­1893) collectedy ­b ­S.K.­Gam­baryan­and­previously­housed­in­VLA­ The ­genus­includes­21­species­and­is­distributed­mostly­ (now ­trans­fer­red­to­VBGI)­were­taken­into­account.­All­dis- pan­tro­pically,­ although­ spreading­ both­ southward­ and­ tributiona ­dat ­were­re-checked­in­the­course­of ­the­pre­pa­ra- north­ward­of ­the­tropical­zone.­The­only­taxon­known­in­ tion ­of ­the­pre­sent­account­and­the­distribution­provided­for­ the Russian Far East is Acrolejeunea sandvicensis­s and­it ­loca­li- each ­species­is­based­on­studied­materials­with­rare­excep- tiese ­ar ­the­northernmost­for­the­genus­worldwide.­Before­it­ tion, ­ where­ cited.­ The­ valuable­ vouchers­ (commonly­ one­ was ­known­in­Russia­as­Trocholejeunea