Taxonomic and Photographic Guide to the Acanthaceae of Tamaulipas, Mexico Author Daniel, Thomas F. Department of Botany, California Academy of Sciences, 55 Music Concourse Drive, San Francisco, California 94118, U. S. A. tdaniel@calacademy.org Author García-Morales, Leccinum J. Herbario, Departamento de Posgrado e Investigación, Instituto Tecnológico de Ciudad Victoria, Blvd. Emilio Portes Gil 1301, Cd. Victoria, Tamaulipas, México; Author Mora-Olivo, Arturo Instituto de Ecología Aplicada, Universidad Autónoma de Tamaulipas, División del Golfo 356, Cd. Victoria 87019, Tamaulipas, México; text Proceedings of the California Academy of Sciences 2021 2021-09-30 67 6 185 228 journal article 10.5281/zenodo.11513051 0068-547X 11513051 Ruellia simplex Wright PHENOLOGY .— Flowering: July–April; fruiting: April, July–December. DISTRIBUTION .— Mexico (Ags., Camp., Chis., Gro., Hgo., Oax., Pue., Qro., Q.R., S.L.P., Sin., Son., Tab., Tamps., Ver., Yuc.), West Indies, Central America, South America. HABITAT .— Aquatic and riparian vegetation. ELEVATION .— 12–330 meters. NOTES .— Daniel (1995) and Daniel and Acosta C. (2003) provided descriptions of this species under the name R. coerulea Morong. The species reaches the northernmost extent of its presumably native distribution in Tamaulipas. The names R. brittoniana Leonard and R. coerulea are often applied to plants of the species with very narrow leaves (e.g., Mora-Olivo 5688 , Mora-Olivo & Galván 7647 ), and R. malacosperma Greenm. is often applied to plants with somewhat wider leaves (e.g., Mora-Olivo 5689 , Pringle 6806 ). Plants of R. simplex are often cultivated and sometimes become naturalized (e.g., U.S.A. ). Flowers of cultivated plants vary from blue-purple ( Fig. 5E ) to pink to white ( Fig. 5F ). The native distribution in the Neotropics is not known with certainty, and possible native occurrences in some of the Mexican states listed above may instead reflect naturalized occurrences. The type of R. malacosperma ( Pringle 6806 ) is from Tamaulipas. REPRESENTATIVE SPECIMENS .— Mpio. Gómez Farías , Río Sabinas , falda de la Sierra de Gómez Farías, M . Chazaro B. 1332 ( XAL ) ; El Coyote Creek , 5 km S of Nuevo Laredo , M. Domínguez M. 45 ( TEX ) ; Mpio. Victoria, S del Bosque Urbano , Cd. Victoria, L . García-Morales 1951 ( ITCV ); Río San Marcos , ca. Col. Horacio Terán, Cd. Victoria, L. García-Morales 2034 ( ITCV ); KM 2 Cañón de La Peregrina, L. García-Morales 5184 ( ITCV ) ; Mpio. Tampico , Laguna de Tancol , 22°18ʹ00ʺN , 097°53ʹ57ʺW , A. Mora-Olivo 1775 (MEXU-image, UAT ) ; Mpio. Gómez-Farías , Reserva de la Biósfera El Cielo , Río Frio , en el Puente , 22°57ʹ20ʺN , 099°07ʹ30ʺW , A. Mora-Olivo 5075 ( UAT ) ; Mpio. Llera , Reserva de la Biósfera “El Cielo,” Ejido La Libertad , Río Sabinas , 23°08ʹ06ʺN , 099°09ʹ00ʺW , A. Mora-Olivo 5457 ( UAT ) ; Mpio. Victoria , Cd. Victoria , Arroyo María , Fraccionamiento Villa Real , A. Mora-Olivo 5688 ( MEXU , UAT ), 5689 (MEXU, UAT) ; Mpio. Gómez Farías , Rio Guayalejo , poblado La Esperanza , en el puente, 22°56ʹ56.7ʺN , 098°59ʹ53.1ʺW , A. Mora-Olivo 8488 ( UAT ) ; Mpio. Mante , Río Guayalejo , El Limón , A. Mora-Olivo & M. Galván 7647 (MEXU-image, UAT ) ; Mpio. Valle Hermoso , Distrito de Riego 025 Bajo Río Bravo , A. Mora-Olivo & J. Mora-López 5209 ( UAT ) ; Tampico, C . Pringle 6806 ( lectotype : GH-image!; isolectotypes : BM!, BR!, F!, GH!, K!, L!, LL, MEXU, MIN!, NSW!, NY, P!, PR!, PRC!, S!, UC!, US, W!); along Río Sabinas , E. Storms’ “Rancho de Las Calavasas,” opposite KM 619 on Pan American Hwy. , N of El Limón , A. Sharp & E. Hernández X. 50/50385 ( GH ) ; edge of Río Sabinas , W of El Encino , A. Sharp & D. Richards MV-741 (USF-image) .