Assessing the evolutionary history of the fern family Dipteridaceae (Gleicheniales) by incorporating both extant and extinct members in a combined phylogenetic study

Abstract

Overall, the evolutionary trend in Dipteridaceae has been toward increasing complexity in the venation pattern and laminal fusion. Only the Hausmannia-type frond with dichotomizing primary veins and relatively fused lamina persisted in the later part of the Mesozoic to the present. Within the crown group, we see evidence of re-radiation of frond forms in Dipteris and Cheiropleuria.

Mountains, climate and niche heterogeneity explain global patterns of fern diversity

“…Although we find evidence of rapid, recent speciation in some areas (e.g. the Papuan Highlands and Borneo; (Choo & Escapa, 2018;Regalado et al, 2018). The importance of Malesia as both a biodiversity hotspot and 'museum' has been noted for other groups (Steenis, 1979) and reflects the signature of the region's complex palaeogeographical and climatic histories on its biota.…”

“…Compared to other global hotspots, the high fern diversity observed in Malesia appears to be largely due to the persistence of ancient endemic lineages. Most Malesian ferns are found nowhere else on Earth (Figure 2), including members of relictual, once widespread, families such as Cystodiaceae and Matoniaceae, which are represented in the fossil record dating back hundreds of millions of years(Choo & Escapa, 2018;Regalado et al,…”

Middle-Late Jurassic plant assemblages of the Catlins coast, New Zealand

“…Dipteridaceae have long been considered as indicating relatively warm temperatures (Barnard, 1973;Corsin and Waterlot, 1979), with the single extant genus (Dipteris) confined to the lowland tropics. At least seven genera of Dipteridaceae are recognised Choo and Escapa, 2018), with Mesozoic global generic diversity peaking at five (in four morphological groups, Cantrill, 1995; see also Choo et al, 2016) and local diversity being highest in mid-low latitudes and in humid conditions. For example, in the late Triassic, China had five genera with many species (Zhou et al, 2015), but in the Early Cretaceous, as the region dried, the genera decreased to just Hausmannia and Dictyophyllum.…”

Tree of death: The role of fossils in resolving the overall pattern of plant phylogeny

“…Rothwell et al. () and Choo and Escapa () address the overall patterns of phylogeny for marattialean ferns and dipteridacean ferns, respectively. Both studies highlight the fact that living species comprise only minor components of diverse and species‐rich clades with long fossil records and high levels of extinction.…”

“…For the Marattiales, alternative outgroup selections for the clade reveal that relationships among genera with living species are not as clearly resolved as commonly believed (Rothwell et al., ). For the Dipteridaceae, the Choo and Escapa () analysis reveals that morphological diversity found in living genera is only a fraction of the morphological diversity present in the Mesozoic. This study represents the first morphological phylogenetic analysis for Dipteridaceae, and taxonomic treatments for extinct species of the family are proposed.…”