Survey of the vascular plants of Alert (Ellesmere Island, Canada), a polar desert at the northern tip of the Americas Author Desjardins, Émilie Author Lai, Sandra Author Payette, Serge Author Dubé, Martin Author Sokoloff, Paul C. Author St-Louis, Annie Author Poulin, Marie-Pier Author Legros, Jade Author Sirois, Luc Author Vézina, François Author Tam, Andrew Author Berteaux, Dominique text Check List 2021 2021-02-09 17 1 181 225 http://dx.doi.org/10.15560/17.1.181 journal article 10.15560/17.1.181 1809-127X Stellaria longipes Goldie subsp. longipes Figure 6F, G Materials examined. CANADA – Nunavut • Ellesmere Island , CFS Alert ; 82°29′59″N , 062°27′56″W ; 82 m a.s.l. ; 27 Jul. 2019 ; habitat: xeric in a slope, with polygonal patterned ground made of till and rocks, and sparse dominance of Saxifraga oppositifolia ; QFA0635575 . Identification. Plants 1–8 cm high; herbaceous; caespitose. Taproots and thin rhizomes present. Stems 2–8 cm long; prostrate, decumbent, or erect; glabrous. Axillary branches present. Leaves cauline; opposite; sessile. Cauline leaf blades 4–9 mm long, 1.1–3.0 mm wide; lanceolate; appearing single-veined (midrib prominent); abaxial surface keeled; abaxial and adaxial surfaces both glabrous; margins glabrous; apices acute or acuminate. Inflorescence a solitary flower or a dichasium, with 2 flowers. Bracts 2.2–7.0 mm long, 0.6–2.0 mm wide. Ped- icels glabrous. Sepals 5; 2–4 mm long, 1.0– 1.5 mm wide; lanceolate; green, with hyaline margins; surface; margins ciliate; apices acute. Petals 5; 3–5 mm long, 3–4 mm wide; obovate or obtriangular; deeply cleft; white. Androecium with 8–10 stamens and 0.6–0.8 mm long, red anthers. Gynoecium with 3 styles and 1 stigma per style. The deeply cleft petals distinguish Stellaria species from the other Caryophyllaceae genus ( Aiken et al. 2007 ). S. longipes subsp. longipes can be differenti- ated from the two other Stellaria species on present on Ellesmere Island ( GBIF 2020) by the following: S . lon- gipes has red anthers, whereas S. humifusa Rottbøll and S. crassifolia Ehrhart have yellow anthers ( Aiken et al. 2007 ); and S. longipes has strongly keeled leaf blades with midvein prominent, whereas S. humifusa and S. crassifolia have flat leaf blades with midvein obscure ( Saarela et al. 2020 ). Cyperaceae – Sedge family