Language: English with trilingual summary in English, French, and Dutch
Dicranolejeunea is reduced from 50 validly published names to 8 species and is divided into two genera: Dicranolejeunea with one species; D. axillaris, and Acanthocoleus which contains the remaining 7 species. One species of Acanthocoleus is described as new.
Characters used in this monograph are taken from stem anatomy, leaf position in the dry state, leaf cells, position of the male bracts and lobule morphology. Leaf form, perianth and gynoecial characters are shown to be too variable for species delimitation and, as branching characters, can be used in a restricted sense only.
A key to the species is provided for fertile, sterile and hygrophytic plants. A key to related genera in the tribe Brachiolejeuneae is given. based on vegetative characters.
The genera Dicranolejeunea and Acanthocoleus are fully documented and all species are fully described and illustrated. Distribution maps and a discussion on the origins of present-day distribution patterns are also provided.
The joined phylogenetic analysis of Dicranolejeunea and Acanthocoleus provides arguments for the separation of the two groups on generic level. A discussion on generic relationships is given in the context of outgroup selection.
A list of excluded species and one containing invalid names in both Dicranolejeunea and Acanthocoleus is added to prevent future confusion.
I. History 8
II. Morphology and anatomy 10
a. Introduction 10
b. Habitus 10
c. Branching 10
d. Stem structure 14
e. Ventral merophyte 14
f. Leaves 15
g. Leaf cells 15
h. Oil bodies 16
i. Pigmentation 17
j. Underleaves, underleaf attachment and rhizoids 17
k. Androecia 17
l. Gynoecia 18
m. Sporophyte 19
n. Chemistry 20
III. Phylogenetic analysis 21
a. Introduction and key to related genera 21
b. Selection of the outgroup 23
Acanthocoleus and Lopholejeunea 23
Dicranolejeunea, Acanthocoleus and Odontolejeunea 25
Dicranolejeunea, Acanthocoleus and Brachiolejeunea 26
c. The construction of the cladogram 32
d. Conclusions 38
e. Geographical analysis 38
IV. Division and Key 42
a. Conspectus 42
b. Key to the species 43
V. Dicranolejeunea 47
Dicranolejeunea axillaris 47
VI. Acanthocoleus 59
Acanthocoleus aberrans 62
Acanthocoleus chrysophyllus 72
Acanthocoleus gilvus 79
Acanthocoleus javanicus 85
Acanthocoleus juddii 93
Acanthocoleus madagascariensis 98
Acanthocoleus yoshinaganus 105
VII. Nomenclature of not accepted species 111
a. Excluded species 111
b. Species assigned to Lejeunea subs. Dicranolejeunea 117
c. Dubious names 117
d. Invalid names 118
VIII. References 119
IX. Summary/Samenvatting/Resume 127
Acknowledgements 131
X. Index on taxa 132