Schizaeaceae: a phylogenetic approach
Schizaeaceae fossils have been documented throughout Mesozoic and Cenozoic deposits, but our understanding of this fossil record is hampered by uncertainties with respect to the relationships of living species. To start building a phylogenetic framework for the family, an initial phylogenetic analys...
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Published in | Review of palaeobotany and palynology Vol. 119; no. 1; pp. 35 - 50 |
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Main Authors | , , |
Format | Journal Article |
Language | English |
Published |
Elsevier B.V
01.05.2002
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Subjects | |
Online Access | Get full text |
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Summary: | Schizaeaceae fossils have been documented throughout Mesozoic and Cenozoic deposits, but our understanding of this fossil record is hampered by uncertainties with respect to the relationships of living species. To start building a phylogenetic framework for the family, an initial phylogenetic analysis of living species using plastid
rbcL nucleotide sequence data is conducted. The analysis supports
Schizaea s. lat. and
Lygodium monophyly, but
Anemia is resolved as paraphyletic to
Mohria. In the
Anemia/
Mohria clade, monophyly of subgenus Anemiorrhiza is supported, but Coptophyllum is resolved as paraphyletic to subgenus Anemia. In
Schizaea s. lat., both
Schizaea s. str. and
Actinostachys are well supported and
Microschizaea is grouped with
Schizaea s. str., although only one
Microschizaea species (
Schizaea pusilla) was included. These results are largely congruent with previous morphology-based analyses. In
Lygodium however, results presented contrast with recent morphological analyses highlighting the problems of identifying
Lygodium subgeneric groups. Using the resulting phylogeny as a framework, putative relationships of fossil species are discussed, tentative minimum age estimates for generic crown group diversifications are made, and possible conclusions with respect to the origins of habit and habitat preferences are discussed. The fossil evidence indicates that subgeneric groups within the
Anemia/
Mohria clade are comparatively ancient, originating during the Early Cretaceous, and the putative placement of fossil
Anemia within the crown group of living subgenus Anemiorrhiza would indicate that their calcareous habitat preference may be a relic feature that has persisted ever since the Early Cretaceous.
Lygodium on the other hand appears to have passed through a diversity bottleneck. Modern species diversity probably originated in the Neogene, and the earliest fossil evidence for the origin of their vining and trailing habit comes from the placement of Miocene fossil
Lygodium within the crown group of living species. |
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ISSN: | 0034-6667 1879-0615 |
DOI: | 10.1016/S0034-6667(01)00128-2 |