Cytisus kreczetoviczii Wissjul. in Zerov, Fl. URSR 6: 586 (1954)

Sennikov, Alexander N. & Tikhomirov, Valery N., 2024, Atlas Florae Europaeae notes, 33. Taxonomic synopsis of East European species of the Cytisus ratisbonensis group (Fabaceae), PhytoKeys 238, pp. 157-197 : 157

2. Cytisus kreczetoviczii Wissjul. in Zerov, Fl. URSR 6: 586 (1954)

- Chamaecytisus kreczetoviczii (Wissjul.) Holub in Folia Geobot. Phytotax. 11: 83 (1976) - Chamaecytisus ruthenicus var. kreczetoviczii (Wissjul.) Skalická in Rad. Akad. Nauka Um. Bosne Hercegovine 72: 241 (1983) - Cytisus ruthenicus subsp. kreczetoviczii (Wissjul.) Cristof. in Webbia 45: 214 (1991).

Type.

Ukraine. "Prope flum. Gruzkyj Jelanczyk, loco Charcysska balka dicto, in decliviis calcareis sarmaticis," 23.05.1926, Yu.D. Kleopov (lectotype KW000022339, designated by Krytzka et al. (1999: 610); isolectotypes KW000022338, KW000022340, possible isolectotype KW000022341). Fig. 3 .

Description.

Upright shrubs with erect stems up to 80 cm tall and long branches. Leaves with lanceolate to elliptic leaflets, sparsely hairy above, with appressed hairs 0.1-0.2(0.4) mm long below, petioles sparsely covered with laxly appressed (partly subpatent) hairs. Flowers strictly lateral, 1-4 in axils, on pedicels 4-6 mm long, yellow; calyx 10-12 mm long, with (laxly) appressed hairs 0.4-0.6(0.8) mm long; standard suborbicular, glabrous or sparsely hairy above.

Distribution.

Europe: Belarus (new record), Ukraine, Russia ( Tzvelev 1987). Reported for the first time from Belarus here.

Ecology.

Alluvial sands in larger river valleys, riverside slopes, often on exposed calcareous substrates.

Chromosome counts.

2n = 100 ( Parfionaŭ et al. 1975, as Chamaecytisus sp.); material collected from native populations in Gomel Region; vouchers at MSK.

Notes on nomenclature.

The type specimen of Cytisus kreczetoviczii was interpreted as holotype by Krytzka et al. (1999: 610). Since the holotype specimen was not indicated in collections by the author and the type collection was represented by multiple duplicates, Fedoronchuk et al. (2003: 96) formally designated a lectotype. However, in this case, the earlier holotype indication is correctable to lectotypification because of its having been published prior to 2001 ( Turland et al. 2018).

Notes on taxonomy and distribution.

This is a variable taxon, which occupies an intermediate position between C. borysthenicus and C. ruthenicus in the shape of leaves and the pubescence of the upper side of leaves. Taxonomically, these plants were recognised as a locally endemic species in Ukraine ( Wissjulina 1954) and as an unnamed hybrid in Russia ( Tzvelev 1987). Tzvelev (1987) misinterpreted C. kreczetoviczii as another alleged hybrid, between C. ruthenicus and C. wulffii . The latter taxon has hairy upper surfaces of leaves, but its creeping habit and a narrowly restricted distribution in the mountainous Crimea makes its participation in any hybridisation outside the mountains highly unlikely. Cytisus kreczetoviczii has tall and erect branches and narrowly lanceolate leaves ( Wissjulina 1954), and its occurrence within the overlapping distributions of C. ruthenicus and C. borysthenicus agrees with its intermediate morphology between the two latter species. The reduction of this taxon to C. ruthenicus , as proposed by Skalická (1983) and Cristofolini (1991), is not justified because C. kreczetoviczii differs from C. ruthenicus by its stems, petioles and pedicels covered with subappressed hairs 0.6-0.8 mm long (vs. 0.4-0.6 mm long in C. ruthenicus ) and its lanceolate to elliptic (vs. obovate) leaflets variously hairy (vs. glabrous) above. This taxon largely occurs in mixed populations together with its parental species, although some localities (including the type one) can be found without direct connection with the parents. It advances further northwards than C. borysthenicus and occurs in Belarus in the absence of the latter.

Figures

Figure 3. Lectotype of Cytisus kreczetoviczii Wissjul.