Describing new fossil taxa is an important focus of work in the lab. We use morphology and anatomy to better understand the evolutionary history and phylogenetic relationships of plants, particularly groups that are extinct and thus only known from fossils. Most work to date has focused on Mesozoic plants, but also includes a range of time periods from the Carboniferous to the Miocene.
Previous and ongoing projects have focused on exceptionally preserved non-flowering seed plants from Early Cretaceous lignites in Mongolia. This flora is especially rich in conifers and contains many well-preserved seed cones, leaves, and shoots that help to shed light on the past diversity, morphological disparity, and evolutionary relationships of both living and extinct conifer groups.
Several current projects are focused on Jurassic conifers from Patagonia, particularly members of the extinct family Cheirolepidiaceae. The phylogenetic position of this group is uncertain, but it shares morphological and anatomical features with several living clades including Araucariaceae, Podocarpaceae, and possibly the Pinaceae. Resolving the phylogenetic position and evolutionary history of this group is important because it may help to break up the long morphological branches that separate the extant conifer clades, and therefore help to resolve deep patterns of character evolution among conifers.
Shi, G., Leslie, A.B., Herendeen, P.S., Herrera, F., Ichinnorov, N., Takahashi, M., Knopf, P. and Crane, P.R., 2016. Early Cretaceous Umkomasia from Mongolia: implications for homology of corystosperm cupules. New Phytologist 210: 1418-1429.
Herrera, F., Shi, G., Leslie, A.B., Ichinnorov, N., Takahashi, M., Knopf, P., Crane, P.R., Herendeen, P.S. 2015. A new Voltzian seed cone from the Early Cretaceous of Mongolia and its implications for the evolution of ancient conifers. International Journal of Plant Sciences 176: 791-809.
Shi, G., Leslie, A.B., Herendeen, P.S., Ichinnorov, N., Takahashi, M., Knopf, P., Crane, P.R. 2014. Whole-plant reconstruction and phylogenetic relationships of Elatides zhoui sp. nov. (Cupressaceae) from the Early Cretaceous of Mongolia. International Journal of Plant Sciences 175: 911-930.
Leslie, A.B., Glasspool, I., Herendeen, P.S., Ichinnorov, N., Knopf, P., Takahashi, M., Crane, P.R. 2013. Pinaceae-like reproductive morphology in Schizolepidopsis canicularis, sp. nov. from the Early Cretaceous (Aptian-Albian) of Mongolia. American Journal of Botany 100: 2426-2436.