Rostraria cristata (L.) Tzvelev

Family: Poaceae, Tribe: Aveneae

Pertinent Synonyms & Notes (particularly those used in California; go to GRIN for other synonyms)

Koeleria phleoides (Vill.) Pers., Festuca cristata L.

Pertinent Common Names (particularly those used in California; go to GRIN for other common names)

annual junegrass

Primary Disseminule Type


Description (diagnostics are in brown)

Spikelets solitary, pedicelled (pedicels oblong), consisting of 3–8 fertile florets, sometimes with a similar-looking though diminished sterile floret at apex, oblong, laterally compressed, 2.8–7.5 mm long. Disarticulation below each fertile floret, although terminal groupings of florets are not unusual.

Glumes persistent, similar, reaching apex of florets or shorter than spikelet, membranous, shiny, gaping, without keel, surface glabrous or puberulous. Lower glume lanceolate, 2–3 mm long, 0.6–0.75 length of upper glume, 1-veined, apex acuminate. Upper glume elliptic, 3–4 mm long, same length as adjacent fertile lemma, faintly 3–5-veined, margins hyaline, apex acute.

Fertile florets: rachilla persistent, very short, pubescent, callus very short, pubescent. Lemma oblong, 2.5–4 mm long, membranous, hyaline on margins, shiny, keeled, 5-veined, lateral veins ± ribbed, surface smooth, tuberculate or scabrous, glabrous or pubescent, apex obtuse to acute, entire or bifid, mucronate or awn subapical, 0–3 mm long.

Palea shorter than lemma, hyaline, gaping, keels scaberulous, apex minutely bifid.

Caryopsis lanceolate, strongly laterally compressed, ca. 1.8 mm long x ca. 0.5 mm wide, brown, embryo <0.25 length of caryopsis, hilum short.

Risk Assessment (codes in yellow or red indicate cause for concern; assessments are current as of mid-2011; click AUQP, NZBORIC, or NZBPI for access to the most recent versions of these databases and possible assessment changes)