Abstract
The rediscovery of Erigeron morelensis, not collected since 1898, is reported. Between 2021 and 2022, E. morelensis was recorded at two sites in the northwestern canyons of Cuernavaca, Morelos, Mexico, which are subjected to degradation pressure. The morphological description is updated and complemented, and a key for E. sect. Erigeridium is included. Data about the known distribution, ecology and habitat of the species are provided. Based on the IUCN criteria, it is recommended that the species be listed as Critically Endangered (CR).
References
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<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">IUCN (2022) </span><span lang="en-GB"><em>The IUCN red list categories and criteria, version 2021-3</em></span><span lang="en-GB">. IUCN Red List Unit, Gland, Switzerland and Cambridge, UK. Available from: https://www.iucnredlist.org (accessed 4 April 2022)</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Linnaeus, C. (1753) </span><span lang="en-GB"><em>Species Plantarum</em></span><span lang="en-GB">. L. vols. 1–2. Impensis Laurentii Salvii, Holmiæ, 1200 pp. https://doi.org/10.5962/bhl.title.669</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Nesom, G.L. (1981) Five new species of Mexican </span><span lang="en-GB"><em>Erigeron </em></span><span lang="en-GB">(Asteraceae). </span><span lang="en-GB"><em>Madroño</em></span><span lang="en-GB"> 28: 136–147. https://www.jstor.org/stable/41424315</span></span></span></span></p>
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<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Nesom, G.L. (2008) Classification of subtribe Conyzinae (Asteraceae: Astereae). </span><span lang="en-GB"><em>Lundellia</em></span><span lang="en-GB"> 11: 8–38. https://doi.org/10.25224/1097-993X-1.11.8</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Nesom, G.L. (2020) Revised subtribal classification of Astereae (Asteraceae). </span><span lang="en-GB"><em>Phytoneuron</em></span><span lang="en-GB"> 53: 1–39. [https://www.phytoneuron.net/2020Phytoneuron/53PhytoN-AstereaeSubtribes.pdf]</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Nesom, G.L. & Robinson, H. (2007) Tribe Astereae Cass. (1819). </span><span lang="en-GB"><em>In</em></span><span lang="en-GB">: Kadereit, J.W. & Jeffrey, C. (Eds.) </span><span lang="en-GB"><em>The Families and Genera of Vascular Plants. Vol. 8 Flowering Plants. Eudicots. Asterales</em></span><span lang="en-GB">. Springer, Berlin, pp. 339–341.</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Nicholson, R. (2001) The splendid haul of Cyrus Guernsey Pringle. </span><span lang="en-GB"><em>Arnoldia</em></span><span lang="en-GB"> 61: 2–9. [https://www.jstor.org/stable/42954832]</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">NOAA (2022) </span><span lang="en-GB"><em>National Centers for Environmental information, Climate at a Glance: Global Rankings</em></span><span lang="en-GB">. Available from: https://www.ncdc.noaa.gov/cag/ (accessed: 25 April 2022). </span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Pringle, C.G. (1898) </span><span lang="en-GB"><em>Cyrus Pringle Collection Notebook</em></span><span lang="en-GB">. 14. Available from: https://scholarworks.uvm.edu/cpringle/14 (accessed: 4 April 2022).</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">SEMARNAT Secretaría de Medio Ambiente y Recursos Naturales (2010) </span><span lang="en-GB"><em>Norma Oficial Mexicana NOM-059-SEMARNAT</em></span><span lang="en-GB">, Diario Oficial de la Federación (DOF) (30 de diciembre de 2010). Available from: https://www.gob.mx/profepa/documentos/norma-oficial-mexicana-nom-059-semarnat-2010 (accessed 20 April 2022)</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Torrey, A. & Gray, A. (1841) </span><span lang="en-GB"><em>A flora of North America: containing abridged descriptions of all the known indigenous and naturalized plants growing north of Mexico, arranged according to the natural system</em></span><span lang="en-GB">. Wiley and Putman. New York, USA. 711 pp. https://doi.org/10.5962/bhl.title.9466</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Villaseñor, J.L. (2016) Checklist of the native vascular plants of México. </span><span lang="en-GB"><em>Revista Mexicana de Biodiversidad</em></span><span lang="en-GB"> 87: 559–902. https://doi.org/10.1016/j.rmb.2016.06.017</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Villaseñor, J.L. (2018) Diversidad y distribución de la familia Asteraceae en México. </span><span lang="en-GB"><em>Botanical Sciences</em></span><span lang="en-GB"> 96: 332–358. https://doi.org/10.17129/botsci.1872</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">García-Barrios, J.R., Torres, M.G. & Jaramillo, M.F. (2008) </span><span lang="en-GB"><em>Las Barrancas de Cuernavaca, Ciudad de México</em></span><span lang="en-GB">, Universidad Nacional Autónoma de México/Centro Regional de Investigaciones Multidisciplinarias. Available from: https://docplayer.es/22775290-Las-barrancas-de-cuernavaca.html (accessed 6 April 2022)</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Gray, A. (1880) Botanical contributions. </span><span lang="en-GB"><em>Proceedings of the American Academy of Arts and Sciences</em></span><span lang="en-GB"> 15: 25–52.</span><span lang="en-GB"> h</span><span lang="en-GB">ttps://doi.org/10.2307/25138561</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Greenman, J.M. (1905) Descriptions of Spermatophytes from the Southwestern United States, Mexico, and Central America. </span><span lang="en-GB"><em>Proceedings of the American Academy of Arts and Sciences</em></span><span lang="en-GB"> 41: 235–270. https://doi.org/10.2307/20013502</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Guerrero, J.A. (2020) Factores de presión a la biodiversidad. </span><span lang="en-GB"><em>In</em></span><span lang="en-GB">: Cruz-Angón, A., Nájera-Cordero, K.C., López-Higareda, D., Melgarejo, E.D., González-Flores, L., Maldonado-Krinis, C., Flores-Ceniceros, M.E. & Fuentes-Vargas, L. (Coords.) </span><span lang="en-GB"><em>La biodiversidad en Morelos</em></span><span lang="en-GB">. Estudio de estado 2. Vol. III. CONABIO, México pp. 127–132. Available from: https://biodiversidad.morelos.gob.mx/biodiversidad/libro-estudio-de-estado-2 (accessed 1 March 2022)</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">IUCN (2022) </span><span lang="en-GB"><em>The IUCN red list categories and criteria, version 2021-3</em></span><span lang="en-GB">. IUCN Red List Unit, Gland, Switzerland and Cambridge, UK. Available from: https://www.iucnredlist.org (accessed 4 April 2022)</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Linnaeus, C. (1753) </span><span lang="en-GB"><em>Species Plantarum</em></span><span lang="en-GB">. L. vols. 1–2. Impensis Laurentii Salvii, Holmiæ, 1200 pp. https://doi.org/10.5962/bhl.title.669</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Nesom, G.L. (1981) Five new species of Mexican </span><span lang="en-GB"><em>Erigeron </em></span><span lang="en-GB">(Asteraceae). </span><span lang="en-GB"><em>Madroño</em></span><span lang="en-GB"> 28: 136–147. https://www.jstor.org/stable/41424315</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Nesom, G.L. (1989a) Four new species of </span><span lang="en-GB"><em>Erigeron</em></span><span lang="en-GB"> (Compositae): Astereae) from northern México. </span><span lang="en-GB"><em>Phytologia</em></span><span lang="en-GB"> 66: 488–495. https://doi.org/10.5962/bhl.part.9299</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Nesom, G.L. (1989b) The infrageneric taxonomy of New World </span><span lang="en-GB"><em>Erigeron </em></span><span lang="en-GB">(Compositae: Astereae). </span><span lang="en-GB"><em>Phytologia</em></span><span lang="en-GB"> 67: 67–93. https://biostor.org/reference/62863</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Nesom, G.L. (2008) Classification of subtribe Conyzinae (Asteraceae: Astereae). </span><span lang="en-GB"><em>Lundellia</em></span><span lang="en-GB"> 11: 8–38. https://doi.org/10.25224/1097-993X-1.11.8</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Nesom, G.L. (2020) Revised subtribal classification of Astereae (Asteraceae). </span><span lang="en-GB"><em>Phytoneuron</em></span><span lang="en-GB"> 53: 1–39. [https://www.phytoneuron.net/2020Phytoneuron/53PhytoN-AstereaeSubtribes.pdf]</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Nesom, G.L. & Robinson, H. (2007) Tribe Astereae Cass. (1819). </span><span lang="en-GB"><em>In</em></span><span lang="en-GB">: Kadereit, J.W. & Jeffrey, C. (Eds.) </span><span lang="en-GB"><em>The Families and Genera of Vascular Plants. Vol. 8 Flowering Plants. Eudicots. Asterales</em></span><span lang="en-GB">. Springer, Berlin, pp. 339–341.</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Nicholson, R. (2001) The splendid haul of Cyrus Guernsey Pringle. </span><span lang="en-GB"><em>Arnoldia</em></span><span lang="en-GB"> 61: 2–9. [https://www.jstor.org/stable/42954832]</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">NOAA (2022) </span><span lang="en-GB"><em>National Centers for Environmental information, Climate at a Glance: Global Rankings</em></span><span lang="en-GB">. Available from: https://www.ncdc.noaa.gov/cag/ (accessed: 25 April 2022). </span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Pringle, C.G. (1898) </span><span lang="en-GB"><em>Cyrus Pringle Collection Notebook</em></span><span lang="en-GB">. 14. Available from: https://scholarworks.uvm.edu/cpringle/14 (accessed: 4 April 2022).</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">SEMARNAT Secretaría de Medio Ambiente y Recursos Naturales (2010) </span><span lang="en-GB"><em>Norma Oficial Mexicana NOM-059-SEMARNAT</em></span><span lang="en-GB">, Diario Oficial de la Federación (DOF) (30 de diciembre de 2010). Available from: https://www.gob.mx/profepa/documentos/norma-oficial-mexicana-nom-059-semarnat-2010 (accessed 20 April 2022)</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Torrey, A. & Gray, A. (1841) </span><span lang="en-GB"><em>A flora of North America: containing abridged descriptions of all the known indigenous and naturalized plants growing north of Mexico, arranged according to the natural system</em></span><span lang="en-GB">. Wiley and Putman. New York, USA. 711 pp. https://doi.org/10.5962/bhl.title.9466</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Villaseñor, J.L. (2016) Checklist of the native vascular plants of México. </span><span lang="en-GB"><em>Revista Mexicana de Biodiversidad</em></span><span lang="en-GB"> 87: 559–902. https://doi.org/10.1016/j.rmb.2016.06.017</span></span></span></span></p>
<p align="justify"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: small;"><span lang="en-GB">Villaseñor, J.L. (2018) Diversidad y distribución de la familia Asteraceae en México. </span><span lang="en-GB"><em>Botanical Sciences</em></span><span lang="en-GB"> 96: 332–358. https://doi.org/10.17129/botsci.1872</span></span></span></span></p>