Systematics and Evolution of the Ericales
The plant order Ericales contains ca. 8000 species of flowering plants distributed in 22 families. The order contains a number of economically important edible plants, including tea (Camellia sinensis), kiwi (Actinidia), persimmon (Diospyros), Brazil nut (Bertholettia excelsa), star-apple (Chrysophyllum cainito), and blueberries and cranberries (Vaccinium), as well as popular ornamental plants such as azaleas and rhododendrons (Rhododendron), primroses (Primula), Impatiens, Erica, Phlox, and Camellia. The order comprises mainly trees and terrestrial shrubs, but some are vines, perennials, or epiphytes. Other families include carnivorous species (e.g., pitcher-plants of Sarraceniaceae) or parasites (e.g., Mitrastemon, Sarcodes).
My research on Ericales employs the study of morphological and molecular data to document species diversity and endemism in the group and understand how it evolved. I ask questions about how many species are in particular subgroups or clades (species discovery and taxonomy), how they should be classified, how they have dispersed from one area of the globe to another (biogeography), and how their features have adapted to their environment. For groups that have a fossil record, I incorporate paleobotanical data to estimate when lineages diverged to better understand how ancient climates changed over the course of the Cenozoic Period (Age of Mammals). Much of my research utilizes phylogenetic trees, that is, estimates of species and higher-order relatedness, for inferring evolution. My scientific program is highly collaborative, involving colleagues at BRIT, at other U.S. institutions, and internationally.
The families that I study most intensively are the silverbell (Styracaceae), sweetleaf (Symplocaceae), and heath or blueberry (Ericaceae) families. With colleagues, I have discovered over 40 species from among these groups, and also described a new genus (Perkinsiodendron). Recent work has includes a comprehensive phylogenetic study of the wintergreen tribe of the heath family (Gaultherieae), in which I and my colleagues inferred the evolution of fruit color variation linked to geographic location and elevation. Current focus extends to the genus Vaccinium (blueberries and cranberries, especially in North America, Polynesia, and Southeast Asia.
2021
Fritsch PW, WB Simison, BC Cruz, EL Schneider, DD Allshouse. 2021. A likely intersectional hybrid in Vaccinium (Ericaceae) on San Bruno Mountain, San Matero County, California. Madroño 67(4):190–210. doi.org/10.3120/0024-9637-67.4.190
Stephan J, PW Fritsch, N Mohanan, D Liriina. 2021. Elevation of Symplocos macrophylla subsp. namboodiriana (Symplocaceae) to the species rank. Phytotaxa 502(1):101–106. doi.org/10.11646/phytotaxa.502.1.8
Stephan J, PW Fritsch, R Akhil. 2021. Symplocos mohananii sp. nov. (Symplocaceae) from the Western Ghats of Kerala, India. Phytotaxa 480(2):195–200. doi.org/10.11646/phytotaxa.480.2.8 [Hindustan Times popular article]
Tamayo MN, RAA Bustamante, PW Fritsch. 2021. Vaccinium exiguum (Ericaceae, Vaccinieae), a new species from the ultramafic summit of Mt. Victoria, Palawan Island, Philippines. PhytoKeys 179:145-154. doi.org/10.3897/phytokeys.179.68323
Yan M-H, C-Y Li, PW Fritsch, J Cai, H-C Wang. 2021. Phylogeny of the Styracaceae revisited based on whole plastome sequences, including novel plastome data from Parastyrax. Systematic Botany 46(1):162-174. doi.org/10.1600/036364421X16128061189576
2020
Fritsch PW, L Lu. 2020. A taxonomic revision of Gaultheria series Trichophyllae (Ericaceae). Journal of the Botanical Research Institute of Texas 14(2):289-341. doi.org/10.17348/jbrit.v14.i2.1010
Fritsch PW, L Lu, CM Bush, SJ Wagstaff, KA Kron. 2020. Phylogenetic analysis supports the allochthonous origin of gynodioecy in New Zealand Gaultheria Kalm ex L. New Zealand Journal of Botany. (Early Online; Nov 2020). doi.org/10.1080/0028825X.2020.1840400
Fritsch PW, P Thomas, V Ly. 2020. A new species of Styrax series Cyrta (Styracaceae) from Cambodia. Journal of the Botanical Research Institute of Texas 14(2):343-347. doi.org/10.17348/jbrit.v14.i2.1011
Fritsch PW, VB Amoroso, FP Coritico, DS Penneys. 2020. Vaccinium hamiguitanense (Ericaceae), a new species from the Philippines. Journal of the Botanical Research Institute of Texas 14(2):281-287. doi.org/10.17348/jbrit.v14.i2.1009
Kron KA, PW Fritsch, L Lu, WS Judd. 2020. New combinations and new and resurrected names in Gaultheria (Ericaceae). Gardens’ Bulletin Singapore 72:299‒317. doi.org/10.26492/gbs72(2).2020-13
Nuraliev M, P Fritsch, A Beer, Y Tong, L Averyanov, A Kuznetsov, S Kuznetsova. 2020. A revision of Vaccinium bullatum (Ericaceae): floral morphology, distribution and typification. Phytotaxa. [Online] 433:1. doi.org/10.11646/phytotaxa.433.1.6
Zhao W, PW Fritsch, Q Fan, W Liao. 2020. Taxonomic reassessment of Rehderodendron gongshanense (Styracaceae) based on herbarium specimens and field observations. Phytotaxa 450(1):1–7. doi.org/10.11646/phytotaxa.450.1.1
Zhao W-Y, PW Fritsch, Z-C Liu, Q Fan, J-H Jin, W-B Liao. 2020. New combinations and synonyms in Rehderodendron (Styracaceae). PhytoKeys 161:79-88. doi.org/10.3897/phytokeys.161.54970
2019
Li G, PW Fritsch. 2019. Notes on several Asian species of Styrax series Cyrta (Styracaceae). J. Bot. Res. Inst. Texas 13(1):249‒251.
Lu L, PW Fritsch, CM Bush, H Wang, KA Kron, D‐Z Li. 2019. Allopolyploidy in the Wintergreen Group of tribe Gaultherieae (Ericaceae) inferred from low‐copy nuclear genes. Nordic J. Botany 37(6). doi.org/10.1111/njb.02077
Lu L, PW Fritsch, NJ Matzke, et al. 2019. Why is fruit colour so variable? Phylogenetic analyses reveal relationships between fruit‐colour evolution, biogeography and diversification. Global Ecol Biogeogr. 00:1–13. doi.org/10.1111/geb.12900
Zhao W-Y, PW Fritsch, VT Do, Q Fan, Q-Y Yin, DS Penneys, U Swensen, W-B Liao. 2019. Rehderodendron truongsonense (Styracaceae), a new species from Vietnam. J. Bot. Res. Inst. Texas 13(1):157–171.
2018
Fritsch PW, C Whitefoord, DL Kelly. 2018. Styrax paulhousei (Styracaceae), a new species from Honduras. J. Bot. Res. Inst. Texas 12:499–505.
Li G, PW Fritsch. 2018. A taxonomic revision of taxa in Styrax series Cyrta (Styracaceae) with valvate corollas. J. Bot. Res. Inst. Texas 12:579–641.
Tiffney BH, SR Manchester, PW Fritsch. 2018. Two new species of Symplocos based on endocarps from the early Miocene Brandon Lignite of Vermont, USA. Acta Palaeobotanica 58:185–198. doi: 10.2478/acpa-2018-0008
Yan M-H, PW Fritsch, MJ Moore, T Feng, A-P Meng, J Yang, T Deng, C-X Zhao, X-H Yao, S Hang, H-C Wang. 2018. Plastome phylogenomics resolves infrafamilial relationships of the Styracaceae and sheds light on the backbone relationships of the Ericales. Molecular Phylogenetics and Evolution 121: 198–211. dx.doi.org/10.1016/j.ympev.2018.01.004