Marchantiaceae

Zheng, Tian-Xiong, Long, David G. & Shimamura, Masaki, 2023, Range extension of Marchantia formosana (Marchantiaceae, Marchantiophyta), with an updated key to Marchantiaceae taxa in East Asia, Phytotaxa 612 (1), pp. 93-98 : 96-97

Key to Marchantiaceae taxa in East Asia

1. Monoicous or dioicous; oil cells in the side walls of air chambers absent in fresh tissues; gemmae and cupules always absent; thallus dichotomous and apical ventral innovations; male receptacle disc-liked and unlobed; alpine or sub-alpine habitats...........2

- Strictly dioicous; oil cells in the side walls of air chambers present in fresh tissues; gemmae and cupules present; thallus strictly dichotomous only; male receptacle lobed; man-made habitats..........................................................................................................4

2. Dioicous; areas of spongy tissue present in dorsal side of thallus ......................................................................... Bucegia romanica

- Monoicous; areas of spongy tissue absent in dorsal side of thallus ...................................................................................................3

3. Thallus robust (up to 15 mm wide); female receptacle lobed, with flat top and highly rough dorsal surface due to dense and prOmInent cOmpOund aIr pOreS; SpOre wIth thIck (5.1–6.6 μm wIde), hIgh (up tO 6 μm) lamellate OrnamentatIOn ............................ .............................................................................................................................................................................. Preissia platycarpa

- Thallus relatively compact (rarely over 10 mm wide); female receptacle shallowly dissected into 4 downward lobes united by 4 cOnvex radIatIng rIdgeS On dOrSal Surface; SpOre wIth thIn (2.1–3.0 μm wIde), lOw (up tO 3 μm) lamellate OrnamentatIOn............... ................................................................................................................................................................................. Preissia quadrata

4. Thallus margin lobulate ......................................................................................................................................................................5

- Thallus margin entire or slightly crisped............................................................................................................................................6

5. Thallus usually growing erect (sometimes prostrate in dry environment) with continuous blackish median band; margin of appendage of median scales entire or crenulate ............................................................ Marchantia polymorpha subsp. polymorpha

- Thallus usually growing prostrate (sometimes erect near water), with discontinuous blackish median band (continuous near water); margin of appendage of median scales with unicellular teeth.......................................................... M. polymorpha subsp. ruderalis

6. Cupule and involucre margin ciliate lobed; oil cells in the side walls of air chambers distinctly whitish when fresh; male receptacle shallowly lobed; appendage of median scales and involucre with oil-cells.......................................................................................7

- Cupule margin ciliate; involucre margin entire, crenulate or ciliate; oil cells in the side walls of air chambers indistinct and nearly hyaline when fresh; male receptacle deeply lobed; appendage of median scales and involucre without oil-cells ............................8

7. Appendage of median scales acute or apiculate apically, usually with toothed or incised margin ..... M. paleacea subsp. paleacea

- Appendage of median scales obtuse apically, with entire or crenulate margin........................................ M. paleacea subsp. diptera

8. Thallus with continuous or discontinuous blackish median band......................................................................................................9

- Thallus without blackish median band.............................................................................................................................................11

9. Appendage of median scales highly pinnatifid .................................................................................................................. M. pinnata

- Appendage of median scales not pinnatifid......................................................................................................................................10

10. Epidermal pores bounded by 6–9 cells, inner opening usually star-shaped; appendages of median scales narrow and strongly acuminate; female receptacle shallowly dissected, lobes shortly grooved, with dorsal surface verrucose due to large and projecting epidermal pores ............................................................................................................................................................. M. subintegra

- Epidermal pores bounded by 4–6 cells, inner opening triangular to hexagonal, sometimes circular; appendages of median scales ovate, triangular to nearly pentagonal, with obtuse or apiculate apex; female receptacle deeply lobed, lobes not grooved, usually apically broadened and emarginate, sometimes truncate, dorsal surface smooth ............................. M. papillata subsp. grossibarba

11. Margin of appendage of median scales with multicellular teeth...................................................... M. emarginata subsp. cuneiloba

- Margin of appendage of median scales with unicellular teeth, crenulate or entire ..........................................................................12

12. Female receptacle shallowly dissected into lobes with short median groove, with strongly verrucose dorsal surface; margin of appendage of median scales nearly entire ................................................................................................................... M. hartlessiana

- Female receptacle shallowly dissected into lobes with truncate or emarginate apex, with nearly smooth dorsal surface; margin of appendage of median scales not entire .............................................................................................................................................13

13. Appendage of median scales with irregularly toothed to nearly entire margin, usually with acute apex; cupule with long cilia (up to 7 cells); involucre ciliate ........................................................................................................................................... M. formosana

- Appendage of median scales with weakly denticulate entire and acute or apiculate apex; cupule with short cilia (up to 5 cells) ..... ............................................................................................................................................................................................... M. longii