Taraxacum danubium A. J. Richards, Acta Fac. Rerum Nat. Univ. Comen., Bot. 18: 108. 1970.

Wolanin, Mateusz, Klichowska, Ewelina, Jedrzejczyk, Iwona, Rewers, Monika & Nobis, Marcin, 2023, Taxonomy and distribution of Taraxacum sect. Erythrosperma (Asteraceae) in Poland, PhytoKeys 224, pp. 1-88 : 1

4. Taraxacum danubium A. J. Richards, Acta Fac. Rerum Nat. Univ. Comen., Bot. 18: 108. 1970.

Taraxacum austriacum danubium ≡ Taraxacum austriacum var. danubium (A. J. Richards) Doll, Feddes Repert. 84: 21. 1973.

Type.

Slovakia, Devinska Kobyla u Bratislavy, 1 May 1968, A. J. Richards (holotype in OXF) .

Description.

Plants usually small, up to 10(-12) cm tall. Leaves greyish-green, dull, sparsely hairy, approximately 3-5(-7) cm long and (1-)1.5-2.5 cm wide, usually 3-4 times longer than wide, blades oblanceolate, usually broadest in upper 1/3, with 3-4 pairs of lateral lobes; lateral lobes opposite to remote; lateral lobes of the inner leaves patent, with a wide abruptly narrowed base and generally slightly widening at the apex, entire or with a few small teeth at the margin; lateral lobes of the outer leaves recurved and obtuse at the apex, entire or occasionally with a few small teeth at the margin; interlobes often with teeth; terminal lobe of the inner leaves triangular, often with a distinct short and obtuse tip; terminal lobe of the outer leaves triangular, obtuse; petioles narrowly winged, pale purplish. Scapes as long as or slightly longer than leaves, reddish-purplish, sparsely hairy in the upper part. Capitulum convex, yellow, 2-3 cm in diameter, ligules with greyish brown-red stripes; inner bracts greyish-green, corniculate; outer bracts usually 10-14, lanceolate, usually 4-6 mm long, 1.5-2.5 mm broad, greyish-green, quite often suffused purple, with a white hyaline margin 0.1(-0.2) mm broad, regularly spreading to quite regularly arranged and recurved, 4-6 mm long, 1.5-2.5 mm broad, corniculate; stigmas greyish-green, pollen present. Achenes dark brown-red, achene body densely spinulose above, 3.3-3.8 mm long (incl. the 0.7-1.0 mm long, narrowly conical cone).

Flowering period.

April (May).

Habitat.

In Poland, this species was observed only in grasslands and crevices of calcareous rocks. Plant communities associated with T. danubium were dominated by species characteristic to the Sedo-Scleranthetea and Festuco-Brometea classes. In Kraków-Częstochowa Upland (Olsztyn place) it was noted as growing together with Allium montanum , Anthyllis vulneraria , Arabis hirsuta , Arrhenatherum elatius , Artemisia campestris , Asperula cynanchica , Briza media , Carex caryophyllea , Centaurea stoebe , Cerastium arvense , C. semidecandrum , Coronilla varia , Dactylis glomerata , Dianthus carthusianorum , Erysimum odoratum , Euphorbia cyparissias , Fragaria viridis , Galium mollugo , Helianthemum nummularium subsp. obscurum , Juniperus communis , Luzula campestris , Medicago falcata , Phleum phleoides , Pilosella officinarum , Plantago lanceolata , P. media , Poa compressa , P. pratensis , Polygala comosa , Potentilla arenaria , Ranunculus bulbosus , Rhamnus cathartica , Sanguisorba minor , Scabiosa ochroleuca , Sedum acre , S. sexangulare , Silene nutans , S. vulgaris , Thymus pulegioides , Veronica spicata , Vincetoxicum hirundinaria .

Somatic chromosome number.

24 ( Wolanin and Musiał 2018).

General distribution.

Central European species reported in the Czech Republic, Hungary, Austria, Slovakia, North-Eastern Germany and Poland ( Uhlemann 2003; Trávníček et al. 2010; Wolanin and Musiał 2018; Štěpánek and Kirschner 2023).

Distribution in Poland.

Very rare, so far only found in the western part of Lesser Poland (Fig. 10D ).

Specimens examined.

DE84 - Olsztyn, rock close to castle, 50°44'59"N, 19°16'47"E, 13 April 2014, M. Wolanin (003453); DE94 - Góra Sfinks, grassland on rock, 50°44'15"N, 19°16'17"E, 12 April 2016, M. Wolanin (003483 UR); DF06 - Mirów, grassland below castle (S slope), 50°36'50"N, 19°28'30"E, 14 April 2014, M. Wolanin (003469 UR); DF68 - between Kryspinów and Bielanany, limestone hill, 16 May 1976, H., T. & J. Tacik (387573 KRAM); DF69 - Kostrze ( Kraków), grassland on rock, 50°02'19"N, 19°52'09"E, 19 April 2015, M. Wolanin (003460 UR); Pychowicka Górka, grassland on rock, 50°01'50"N, 19°53'00"E, 29 April 2013, M. Wolanin (003464 UR); Pychowicka Górka, grassland on rock, 50°01'53"N, 19°52'48"E, 29 April 2013, M. Wolanin (003445 UR); Skały Twardowskiego, grassland on rock, 50°02'27"N, 19°54'15"E, 29 April 2013, M. Wolanin (003448 UR); Kostrze near Kraków, 27 April 1954, W. Kurek, A. Jasiewicz (439049 KRAM); Las Wolski , Przegorzały, calcareous rocks, 4 May 1954, T. Tacik (439037 KRAM); between Skotniki and Pychowice in the vicinity of Kraków, on dry hills, 22 May 1938, J. Lilop (036160, 036161 KRAM); on the Kostrze-Pychowice route, dry limestone hills, 27 April 1957, H. Trzcińska-Tacik (0378960 KRA); Pychowice near Kraków, calcareous rocks, 27 April 1954, A. Jasiewicz (155140 KRA); Pychowice , pasture, 23 April 1951, K. Szczepanek (111697 KRA); Pychowice , hillock, J. Staszkiewicz (407038 KRAM); behind Pychowice , limestone hillocks, 8 May 1953, T. Tacik (387179, 387571 KRAM); DF78 - Podgorki Tynieckie , hill above water hole, 29 May 1975, T. Tacik (387181, 387182 KRAM); Podgorki Tynieckie , limestone hillock, 27 April 1951, T. Tacik (387180 KRAM); Tyniec, hillock, 14 May 1967, J. Błaszczak (063403 KRA) .

Notes.

Species quite small, with sparsely hairy and dull leaves, usually narrow interlobes and side lobes patent or slightly bent, often a little bloated near the ends. Juvenile specimens of T. danubium often have poorly split leaves in the upper part, which makes them similar to T. parnassicum , but due to the presence of pollen, the leaves of T. danubium are hairy and its outer phyllaries longer and wider, and therefore these two species can be easily distinguished. In the populations of T. danubium observed in Poland, the vast majority were young individuals with small rosettes with leaves shaped similarly to the external leaves of several-year-old specimens (Figs 17 , 18 ).

Figures

Figure 10. Distribution maps of Taraxacum sect. Erythrosperma in Poland A T. bellicum B T. brachyglossum C T. cristatum D T. danubium E T. disseminatum F T. dissimile; black square - localities recorded during field studies, black circle - other localities known from herbarium data.

Figure 17. Variation in leaf shape in T. danubium; locality - Olsztyn (M. Wolanin 2016 UR). Scale bar: 5 cm.

Figure 18. Taraxacum danubium; locality - Olsztyn, 2016, photo by M. Wolanin.