Table 1.
List of species used in the study, life form, carbon metabolism, and collection site.
| species | gametophyte morphologya and expected C metabolism | collection site | collector |
|---|---|---|---|
| Marchantiophyta (liverworts) | |||
| Pellia endiviifolia | simple thallus, no pores, C3 | Sart Tilman, Liège, Belgium (banks of Blanc Gravier brook) | M. Meyer |
| Pellia epiphylla | simple thallus, no pores, C3 | River Frome, Stroud, Glos, UK (shaded stones by fast flowing water) | H. Griffiths |
| Conocephalum conicum | complex thallus, pores, C3 | Botanic Garden, Cambridge, UK (weeds in glasshouses) | M. Meyer |
| Lunularia cruciata | complex thallus, pores, C3 | Botanic Garden, Cambridge, UK (weeds outside glasshouses) | M. Meyer |
| Marchantia polymorpha | complex thallus, pores, C3 | Clare College Old Court, Cambridge, UK (between cobbled stones in shade) | M. Meyer |
| Anthocerotophyta (hornworts) | |||
| Megaceros cf. fuegiensis | simple thallus, no pores, no pyrenoid, C3-like | Chile | B. Goffinet |
| Megaceros cf. vincentianus | simple thallus, no pores, pyrenoid mainly in the younger uniplastidic cells of the growing thallus margins but not in the multiplastidic cells elsewhere, CCM? | Alto de Piedra, Santa Fé, Panamá (on rock, growing with Monoclea gottscheii, shaded trail along the border of a patch of forest) | J. C. Villarreal and E. O. Rodriguez |
| Phaeoceros carolinianus | simple thallus, no pores, uniplastidic cells with a pyrenoid, CCM | Australian National Botanic Garden, Canberra, Australia (glasshouse grown on soil) | D. C. Cargill |
| Charophyta | |||
| Coleochaete orbicularis | usually unistratose thallus, pyrenoid, CCM? | UTEX Collection of Algae LB 2651 | L. Graham |
| Chlorophyta | |||
| Chlamydomonas reinhardtii | single cell, pyrenoid, CCM | the chlamydomonas center |
Gametophyte morphology follows Ingrouille & Eddie (2006), and serves as a basis to define three distinct groups. First, simple thalloid bryophytes, with a single or multiple chlorophyllous cell layers on the abaxial and adaxial sides, surrounding a central storage layer, defined as ‘non-ventilated’ thalli, such as the two Pellia spp. and Megaceros fuegiensis. Second, complex thalloid bryophytes with multiple cell layers with some airspaces, where the upper layer containing pores, opening into air chambers bordered by photosynthetic cells and functionally equivalent to mesophyll, defined as ‘well-ventilated’ thalli, such as Conocephalum, Lunularia and Marchantia. Third, species with a biophysical CCM and a pyrenoid, such as hornworts Phaeoceros and M. vincentianus with undifferentiated thalloid tissues and uniplastidic cells, the charophyte and chlorophyte.