Vilnet, A.A., N.A. Konstantinova & A.V. Troitsky. Molecular phylogeny and systematics of the suborder Cephaloziineae with special attention to the family Cephaloziaceae s.l. (Jungermanniales, Marchantiophyta)

Arctoa (2012) 21: 113-132

Molecular phylogenic analysis of the suborder Cephaloziineae is performed, with the special attention to the family Cephaloziaceae s.l. and its implications for taxonomy are discussed. A combined alignment of nuclear ITS1-2 and chloroplast trnL-F DNA sequences of 121 species (209 samples) from the families Scapaniaceae, Anastrophyllaceae, Cephaloziaceae s.l., Cephaloziellaceae, Adelanthaceae, and Jamesoniellaceae are analyzed. The topologies of phylogenetic trees constructed by maximum parsimony, maximum likelihood and Bayesian methods show the principal congruence with previously achieved phylogenies, with exception of ambiguous position of the Cephaloziellaceae. The genus Hygrobiella does not reveal affinity to the Cephaloziaceae s.l., which supports its segregation in the monotypic family Hygrobiellaceae. The Odontoschismataceae are resolved sister to the Cephaloziaceae s.str., supporting their classification into two families expedient also from morphological evidences. The former family preliminarily includes, besides Odontoschisma and Cladopodiella, the genera Iwatsukia and Alobiellopsis from the subfamily Alobielloideae. The relationships of the subfamily Schiffnerioideae remain uncertain. The genera Cephalozia, Odontoschisma and Cladopodiella appear to be polyphyletic, but the existing section subdivisions for Cephalozia and Odontoschisma are partly supported. The genus Nowellia is found in the sister position to Cephalozia bicuspidata-complex and C. macoinii. The rest of studied Cephalozia species compose an intermingled clade with the monotypic genera Pleurocadula and Schofieldia. Thus only species of the Cephalozia bicuspidata-complex and C. macoinii are accepted in Cephalozia, whereas other Cephalozia species and Schofieldia are transferred into the genus Pleurocadula. Infraspecific nucleotide sequence variation suggests the species status for Cephalozia affinis and Odontoschisma elongatum, whereas O. prostratum and O. sphagni appear to be conspecific.