Stellaria ruderalis - NATURESCENE

Stellaire ruderale

Stellaria ruderalis

Chickweed, Wayside

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(des sources variées, pas inclus dans Coste) :

Première description comme novelle espèce dans le monde en 2019 Description de Martin Lepší et al., (Republique de Czech) traduit Probablement malidentifié auparavant comme Stellaria media.
Annuelle d'hiver, vie de courte durée ; souvent verte-jaunâtre, très ramifiée, jusqu'à 80 cm de hauteur. Tiges ascendantes, munies sur un côté d'une ligne de poils entre chaque enternoeud, sans glands. Chromosomes 2n = 44, tetraploid.
Écologie : Espèce ruderale, large gamme d'habitats. species,France : l'Hérault, les Pyrénées orientales, le Var et les Bouches du Rhône (personal communication, James Molina). Trouver par l'auteur à Florac, Causse Méjean.

(various sources, as not in Butcher)
NOTE: the French text is more complete and up-to-date

First described as new world species 2019. Description of Martin Lepší et al.Probably regulary mistaken in the past for Stellaria media.
Winter annual, short-lived, often yellowish-green, much branched, up to 80 cm tall. Stems ascending, with one line of hairs along each internode, eglandular. Number of chromosomes 2n = 44, tetraploid.
Ecology UK: Seen in flower by author in October in Hampshire. General distribution not yet known, but possibly fairly common, confused with other species. France: Ruderal species, wide range of habitats, l'Hérauult, les Pyrénées orientales, le Var et les Bouches du Rhône (personal communication, James Molina). Found by author at Florac & Causse Méjean

Carte (c.2021) grâce à Tela Botanica

Information & Carte (c.2021) France/International grâce à INPN

Fleurs : dischasie terminale, condense au début, ± lache plus tard, avec une ligne des poils et sans glands, ou peu, sur chaque internode ; ratio des longueurs des ramifications de la dischasie (0.7-) 1.1-1.3 (-1.8) cm. Pedicelles reflexes après floraison et érigées après fructification, (1.6-) 2.0-2.8 (-4.0) cm de longueur, (0.16-) 0.24-0.32 (-0.48) mm de largeur, avec une ligne de poils denses, parsemées de quelques glands.. Sépales libres, lanceolate à ovate-lanceolate, (3.9-) 4.9-5.5 (-6.2) mm de longeur, glanduleuses- pubescentes. Pétales 5, blanc, profondément bifides, souvent avec lobes d'une longueur différentes, (2.3-) 3.5-4.1 (-4.8) mm de longueur, plus courtes ou aussi longues que les sépales. Étamines 3-5 (-10) avec anthers pourpre-violette. Styles 3, ascendants, rarement érigées, que l'apex revolute.
Floraison France : septembre et mars à mai (observation de l'auteur)

Flowers: in terminal dichasia, initially condensed, later ± lax, with one line of hairs and no or few glands on each internode; ratio of lengths of the first internodes of dichasium branches (0.7-) 1.1-1.3 (-1.8) cm. Pedicels reflexed after anthesis and erect after fruiting, (1.6-) 2.0-2.8 (-4.0) cm long, (0.16-) 0.24-0.32 (-0.48) mm wide, with one line of dense hairs and an admixture of scattered glands. Sepals free, lanceolate to ovate-lanceolate, (3.9-) 4.9-5.5 (-6.2) mm long, glandular-pubescent. Petals 5, white, deeply bifid, often with lobes unevenly long, (2.3-) 3.5-4.1 (-4.8) mm long, shorter than or as long as sepals. Stamens 3-5 (-10) with purple- violet anthers. Styles 3, ascending, rarely erect, with only the apex revolute.
Flowering UK: In Czech Republic April May. September and March to May in France October in UK (observations of author)

Feuilles : feuilles basales petiolate avec lames ovés à elliptique ; petioles pubescents; feuilles moyens et terminales, et bractées sessiles, lames ovés à elliptique, aigues à acuminés, pointues, à la base arrondies, rarement subcordate, entières, pubescentes sur les nervures centrales, glanduleuses sur les marges ; bractées de la première fleur (1.0-) 1.4-2.5 (-5.0) cm long and (0.4-) 0.8-1.2 (-2.0) cm wide.

Leaves: Lowermost leaves petiolate with ovate to elliptical laminae and pubescent petioles; middle and upper leaves and bracts sessile, laminae ovate to elliptical, acute to acuminate, pointed, rounded to rarely subcordate at base, entire, pubescence on midribs and glands on margins; bracts of the first flower (1.0-) 1.4-2.5 (-5.0) cm long and (0.4-) 0.8-1.2 (-2.0) cm wide.

Fruit : Capsules (5.5-) 6.0-6.4 (-7.0) mm de longueur, un peu plus long que les sépales, ouvrant avec 6 dents. Graines (1.1-) 1.2-1.3 (-1.5) mm de longueur, aplaties, Presque circulaire, brun-clair à brun, avec 5-6 rangs des tubercules sur le surface dorsal, tubercules coniques, plus long que large, (0.08-) 0.11-0.14 (-0.18)mm de longeur, avec (0-) 4-10 (-15) petites papillaes sur le front de chaque tubercule.

Fruit: Capsules (5.5-) 6.0-6.4 (-7.0) mm long, somewhat longer than sepals, opening with 6 teeth. Seeds (1.1-) 1.2-1.3 (-1.5) mm long, flattened, almost circular, light-brown to brown, with 5-6 rows of tubercles on the dorsal surface, tubercles conical, longer than wide, (0.08-) 0.11-0.14 (-0.18)mm long, with (0-) 4-10 (-15) small papillae on the front side of each tubercle.
In petal length and the number of stamens it resembles S. media, which differs significantly in having flat-topped or rounded, rarely shortly conical tubercles on the seeds that are usually as long as wide and with scattered to abundant papillae on their upper part (Figs 9-10). In contrast, S. ruderalis has conical and longer than wide tubercles on seeds, with no or few papillae on their surface. It should be noted that some capsules of S. ruderalis may contain a few seeds that have the same morphology as those of S. media; for reliable identification it is, therefore, necessary to examine several seeds per plant. Other less distinct characters of S. media are a darker (green up to dark green) colour and smaller size (up to 50 cm), often prostrate stems, a lax inflorescence, usually broadly ovate leaves and bracts, and the first internodes of the inflorescence remarkably unevenly long