Stellaria ruderalis M.Lepší, P.Lepší, Z.Kaplan & P.Koutecký

Mokni, Ridha El, Guacchio, Emanuele Del & Iamonico, Duilio, 2023, Further insights into the Stellaria media aggregate (Caryophyllaceae, Alsinoideae, Alsineae) in Africa: first reports of S. ruderalis in North Africa and S. cupaniana in Tunisia, with nomenclatural notes on the name Alsine cupaniana, Phytotaxa 584 (4), pp. 264-274 : 265-268

Stellaria ruderalis M.Lepší, P.Lepší, Z.Kaplan & P.Koutecký in Lepši et al. (2019: 405)

Type: ― CZECH REPUBLIC. Southern Bohemia, Veselí nad Lužnicí (distr. Tábor): Alešovo nábřeží street, slope above Nežárka river , ruderal grassland, 400 m a.s.l., abundant, 3 May 2017, Lepší 88 (holotype CB85744 ; isotype PR929401 ) .

Description ( Fig. 2 ):—Annual or winter annual herb; stems branched, up to 90 cm tall, creeping-ascending with long internodes and with one line of hairs along each internode ( Fig. 2A ); lower leaves petiolate (petiole pubescent), ovate to elliptical; middle and upper leaves and bracts sessile, ovate to elliptical, acute to acuminate, mucronate, usually rounded at the base, entire, not fleshy; flowers grouped in dense inflorescences in terminal dichasia, initially condensed, later laxer with long erect pedicels; sepals 5, free, lanceolate to ovate-lanceolate; petals 5, deeply bifid, shorter than or as long as sepals; stamens 3–5(–10) with purple violet anthers ( Figs 2B–C ); styles 3, ascending, rarely erect, with revolute apex; capsules opening with 6 teeth, somewhat longer than sepals; seeds longer than 1 mm, flattened, almost circular, light-brown to brown with conical and longer than wide tubercles, ca. 0.14 mm long ( Fig. 2D ).

Phenology:—Flowering and fruiting times February–April.

Chromosome number:—2n = 2x = 44 ( Lepší et al. 2019; S. ruderalis is suggested to be an allopolyploid originated from S. pallida and S. neglecta ).

Habitat and distribution in Tunisia:— Stellaria ruderalis occurs in several governorates and it grows on clayey or sandy soils and along roadsides at 2–40 m a.s.l.:

¢ Bizerta-city (Bizerta governorate): Three populations growing along roadsides together with S. media subsp. media , S. pallida , Cymbalaria muralis P.Gaertn., B.Mey. & Scherb. , Lepidium didymum L., Oxalis corniculata L., Parietaria judaica L., Poa infirma Kunth , Polycarpon tetraphyllum (L.) L. subsp. tetraphyllum , Symphyotrichum squamatum (Spreng.) G.L.Nesom , Dysphania ambrosioides (L.) Mosyakin & Clemants, Sisymbrium irio L., and Lysimachia arvensis (L.) U.Manns & Anderb.;

¢ Monastir-city (Monastir governorate): Two populations growing along roadsides together with S. media subsp. media , S. neglecta , S. pallida , Amaranthus viridis L., Lysimachia arvensis , Malva parviflora L., and Oxalis corniculata ;

¢ Jemmal (Monastir): Along roadsides together with Lepidium didymum , Mirabilis jalapa L., Poa infirma , Scolymus maculatus L., Sonchus oleraceus L., and Urtica urens L.;

¢ Moknine (Monastir): Along roadsides together with Chenopodiastrum murale (L.) S.Fuentes, Uotila & Borsch, Emex spinosa (L.) Campd., Fumaria parviflora Lam. , and Urtica urens ;

¢ Nabeul-city (Nabeul governorate): Along the edge of a river together with Chenopodiastrum murale , Lysimachia arvensis , Melilotus sulcatus Desf. , Oxalis pes-caprae L., and Poa infirma ;

¢ Rtiba (Nabeul): At the edge of olive groves together with S. media subsp. media , S. cupaniana , S. pallida , Bellis annua L., Cerastium glomeratum Thuill. , Emex spinosa , Fumaria parviflora , Linaria heterophylla Desf. , L. triphylla (L.) Mill., Malva parviflora , Oxalis pes-caprae , Poa infirma , and Senecio leucanthemifolius Poir. subsp. leucanthemifolius ;

¢ Hammamet-South (Nabeul): Along roadsides together with S. media subsp. media and S. pallida .

Representative specimens examined:— TUNISIA. Bizerta: Bizerta-city , 2 m a.s.l., 11 April 2021, El Mokni s.n. (Herb. El Mokni!) ; Monastir: Monastir-city , 16 m a.s.l., 02 April 2021, El Mokni s.n. (Herb. El Mokni!); Jemmal, 29 m a.s.l., 03 April 2021, El Mokni s.n. (Herb. El Mokni!); Moknine, 2 m a.s.l., 04 April 2021, El Mokni s.n. (Herb. El Mokni!) ; Nabeul: Hammamet-South , about 9 m a.s.l., 22 March 2021, El Mokni s.n. (Herb. El Mokni!); Nabeul-city, 10 m a.s.l., 22 March 2021, El Mokni s.n. (Herb. El Mokni!); Rtiba, 39 m a.s.l., 22 March 2021, El Mokni s.n. (Herb. El Mokni!) .

Figures

FIGURE 2. Stellaria ruderalis in Tunisia. A. Plant habit in one of its natural habitats. B. Summital stems in flowering-fruiting period. C. One inflorescence with opened flower and dried dehiscent capsule. D. Seed shape and form with typical long, conical, dorsal tubercles on the upper part of their surface, scale bar: 1 mm. Photographs by R. El Mokni in Monastir region (Central-Eastern Tunisia), 02 April 2021.