Echinochloa muricata

Authorship sometimes given as (Michx.) Fern. or simply as Fern.; authorship (Beauv.) Fern. is used by Kartesz (1994 and 1999) and by Gleason & Cronquist (1991). This species, as treated by Kartesz (1999), includes a North American native var. microstachya (in which the sometimes-recognized var. wiegandii is included by him), and var. muricata, which he considers exotic to North America. Treated as a "highly variable indigenous species" under the name Echinochloa pallida by Fernald (1950). Gleason & Cronquist (1991), using the same treatment as Kartesz, treats both varieties as native to North America (with the species ranging southward into northern Mexico); Fernald (1950) similarly treats his several varieties as collectively native to the U.S., Canada, and Mexico. Kartesz (1999) divides the various varieties of Fernald's E. pungens between his (Kartesz') two varieties of E. muricata, including placement of some of Fernald's "indigenous" varieties of E. pungens into E. muricata var. muricata, considered exotic in North America by Kartesz. LEM 2Jul01.

Echinochloa muricata is a widespread annual graminoid in a variety of wet habitats occurring throughout the Americas from Newfoundland west to British Columbia in Canada south to Florida, Texas, and California in the United States, Mexico, Central America, and South America. With a large range extent, over 1,200 occurrences, abundant habitat, broad habitat preferences, and no obvious intrinsic vulnerabilities, this species is considered secure.

Echinochloa muricata occurs throughout the Americas from Newfoundland west to British Columbia in Canada south to Florida, Texas, and California in the United States, Mexico, Central America, and South America (Weakley and the Southeastern Flora Team 2023). There are two varieties: E. m. var. microstachya occurs throughout the Americas and E. m. var. muricata is widespread though restricted to North America.

By applying a 1 km separation distance to herbarium specimens and photo-based observations documented between 1993 and 2024, it is estimated that there are over 1,500 occurrences rangewide (GBIF 2024, iNaturalist 2024, SEINet 2024).

Although threats are not widely documented, this species is potentially threatened by development, invasive species, and other threats in some places. However, their overall impact is likely negligible given the species' broad range, large number of occurrences, and no obvious intrinsic vulnerabilities.