Leafy I
Goebelliella cornigera (photo by M. von Konrat) |
This clade is morphologically well defined, compared to the Leafy II clade. It is characterized by:
- Incubous leaf insertion
- Ventral lobules or watersacs (on at least some leaves and/or underleaves)
- Lateral (never ventral) branching
- Endosporic sporeling germination
- Predominantly epiphytic habit
- Male gametangia borne on spicate or capitate lateral branches
Gackstroemia (photo by J. Shaw) |
The group contains all taxa with complicate-bilobed leaves in which the ventral lobe of the leaf is smaller than the dorsal lobe. A portion of the Lepicoleales is unexpectedly also part of the leafy I clade(see Figure 8, Forrest et al., 2006); weight had previously been put upon their reproductive characters in classifications (massive setae, complex protective structures around the developing sporophyte [coelocaules]), but gametophytic characters support their placement in this group.
| Figure 8. Leafy clade I (based on the topology from the 5 partition Bayesian analysis of 5 loci including chloroplast, nuclear, and mitochondrial DNA). Numbers above the branches are Maximum Parsimony bootstrap values/homogeneous Bayesian posterior probabilities (PPs)/5-partition Bayesian PPs/14-partition Bayesian PPs. |
The Lejeuneaceae (Lejeunea cladogyna through Bryopteris filicina), by far the most genus and species-rich family within the liverworts, and Frullania, perhaps the single most speciose genus within the liverworts, are part of this clade. This suggests the possibility that characters associated with this group have driven their diversification.
Frullania asagrayana, with rotifers in the ventral lobules (photo by C. Davis) |
Haplomitriaceae and Treubiaceae
Complex Thalloids and the Blasiaceae
Simple thalloids I
Simple thalloids II plus the Pleuroziaceae
Leafy I
Leafy II
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