Hyparrhenia variabilis and Hyparrhenia cymbaria (Poaceae): New for the Americas, Successful in Mexico

Abstract

Hyparrhenia cymbaria (boat thatching grass, ipopo grass) and Hyparrhenia variabilis (no common name), robust African savanna grasses with complex taxonomies, have not yet been reported for the Americas. Large populations were found in central Jalisco, northeastern Michoacán, and Morelos, Mexico. The species grow in maize and sorghum fields as well as on roadsides and in old fields, but always in association with present or past sorghum cultivation; this suggests introduction through contaminated seed material from Africa. Because of the size and density of the populations, and their native ecology, they are both agricultural pests as well as a potentially dangerous invaders for the American (sub)tropical grasslands and native scrublands, including the southern United States. The invasion underlines the importance of effective phytosanitary controls of the seed supply.

Contribución al conocimiento florístico de la Sierra de los Cardos, Susticacán, Zacatecas, México

“…Esto es de especial atención, ya que ha sido señalada como una especie invasora de amplia distribución que reduce la calidad y cantidad de los servicios ecosistémicos y produce afectaciones a cultivos (Melgoza-Castillo et al 2014, Morales-Romero et al 2019, Leal 2021, lo que pone en riesgo a los pastizales naturales de la región. De acuerdo con Vibrans et al (2014), las gramíneas se han reportado entre las invasoras más dañinas, que a nivel nacional ocupan el primer lugar en especies introducidas.…”