Earliest orchid macrofossils: Early Miocene Dendrobium and Earina (Orchidaceae: Epidendroideae) from New Zealand

Abstract

Fossil leaves of two Early Miocene orchids (Dendrobium and Earina) are reported from New Zealand. The distinctive, raised tetra- to cyclocytic stomatal subsidiary cells of Earina and characteristic papilla-like absorbing glands and "ringed" guard cells of Dendrobium support the placement of the fossils into these genera. These therefore represent the first Orchidaceae macrofossils with cuticular preservation, the oldest records for subfamily Epidendroideae, as well as the first New Zealand and southern hemisphere fossil records for Orchidaceae. These taxa belong in basal clades to the Vandeae/Cymbideae or Epidendreae (Earina) and the Australasian clade of Dendrobium sensu lato. This phylogenetic placement demonstrates expansion of epiphytic orchids into Zealandia by the mid-Cenozoic and an important role for southern continents in the diversification of Orchidaceae.

High-frequency paleoclimate signals from Foulden Maar, Waipiata Volcanic Field, southern New Zealand: An Early Miocene varved lacustrine diatomite deposit

“…comm. 2008;Conran et al, 2009). One fossil flower with in-situ pollen has been described (Bannister et al, 2005).…”

Estimating the age of fire in the Cape flora of South Africa from an orchid phylogeny

“…A single calibration point was used: the crown age of Disa, whose median age was estimated to 19.45 Ma (95% highest posterior density, HPD: 10.2 -30 Ma) by Gustafsson et al [32]. In that study, the dating analysis of Ramirez et al [35], based on a fossil from Dominican amber, was extended with the inclusion of two newly described macrofossils assigned to genera Earina and Dendrobium from New Zealand [36]. In addition, in Gustafsson et al [32] a Bayesian relaxed clock was employed, and the age of fossil Liliacites was not used as a maximum age constraint for crown Asparagales, an assumption made by Ramirez et al [35] that received no support in the cladistic analysis of Doyle et al [37].…”

Evolution along the crassulacean acid metabolism continuum

“…It is difficult, however, to determine the first origin of CAM in plants, especially because the majority of families in which CAM is present originated recently and fossil evidence of CAM has not been discovered (Raven and Spicer 1996). Indeed, Dendrobium and Earina (Epidendroideae) macrofossils of orchid specimens from the early Miocene (23-20 MYA) have been described, however, these were not investigated for the presence of CAM-related characters (Conran et al 2009). Based on the broad diversity of taxa showing CAM compared with species exhibiting C 4 , CAM likely evolved first, and because of the presence of CAM in ancient groups such as the isoetids and cycads, CAM might have appeared as early as the Triassic (Griffiths 1992;Ehleringer and Monson 1993).…”