Juncus fascinatus (Juncaceae), a new combination in Juncus sect. Ozophyllum and notes on morphologically similar species

Abstract

Research of the morphologic variation within Juncus (Juncaceae) sect. Ozophyllum has revealed the need for a new combination, Juncus fascinatus. Univariate and multivariate statistical analyses show that J. fascinatus is morphologically distinct from J. validus. Juncus fascinatus is described, illustrated, and compared to the superficially similar species J. paludosus, J. polycephalos, and J. validus. Juncus fascinatus is endemic to 25 counties in north-central and southeastern Texas whereas J. validus is more widespread and weedy. Juncus fascinatus is distinguished from J. validus by a united capsule apex at dehiscence, capsule length, inner and outer tepal length, length by which the capsule exceeds the tepals, and inflorescence length and width. Juncus validus is ecologically distinct from J. fascinatus and has shown a rapid range expansion throughout the southeastern United States and into the Mid-Atlantic. Juncus validus is most likely non-native west of the Mississippi River. The morphologically similar J. paludosus is reported from Alabama, Georgia, Louisiana, and South Carolina for the first time. Juncus polycephalos is reported from Kansas.

Juncus quartinianus (Juncaceae, sect. Ozophyllum): A Neglected Species from the Horn of Africa and Its Re-Description Based on Morphological SEM Studies

“…Plant height was measured from the base of the culm to the top of the inflorescence. When a character was present more than once per individual (e.g., tepal length), we measured that with the greatest value [3, 6]. Each specimen was treated as an Operational Taxonomic Unit (OTU).…”

“…[5], the largest in the genus Juncus , consists of annuals or rhizomatous to caespitose perennials with terete stems and leaf blades that are perfectly or imperfectly septate. The section comprises about 84 species with centres of distribution in eastern North America, southwestern Europe and the Far East [2, 6]. …”

Vascular Plants of Maryland, USA:

“…There is no specimen backing Redmond's report. Other attributions of J. polycephalus to the state have been based upon Redmond's literature citation or misidentified specimens of J. validus (Knapp 2014).…”

Vascular Plants of Maryland, USA: A Comprehensive Account of the State's Botanical Diversity

“…There is no specimen backing Redmond's report. Other attributions of J. polycephalus to the state have been based upon Redmond's literature citation or misidentified specimens of J. validus (Knapp 2014).…”