Cytisus ratisbonensis Schaeff., Bot. Exped.: tab. in prim. lib. (1760)

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

6. Cytisus ratisbonensis Schaeff., Bot. Exped.: tab. in prim. lib. (1760)

- Cytisus communis Lindem. in Bull. Soc. Imp. Naturalistes Moscou 40(1): 494 (1867), nom. illeg. superfl. - Cytisus hirsutus subsp. ratisbonensis (Schaeff.) Briq., Étud. Cytises Alpes Mar.: 167 (1894) - Chamaecytisus ratisbonensis (Schaeff.) Rothm. in Feddes Repert. 53(2): 143 (1944).

Type.

[icon] Schaeffer, Bot. Exped.: tab. in prim. lib. 1760 (presumably holotype).

Description.

Prostrate shrubs up to 20 cm above ground with long branches. Leaves with obovate to elliptic leaflets, glabrous above, with appressed hairs 0.4-0.8 mm long below, petioles densely covered with appressed hairs. Flowers strictly lateral, 1-4 in axils, on pedicels 3-5(7) mm long, pale yellow; calyx 11-14 mm long, with laxly appressed hairs 0.8-1.2(1.6) mm long; standard suborbicular, glabrous above.

Distribution.

Europe: Austria ( Heywood and Frodin 1968), Germany ( Heywood and Frodin 1968), Czech Republic ( Skalická 1995; Kaplan et al. 2019), Hungary ( Pifkó 2009b), Bulgaria ( Heywood and Frodin 1968; Cristofolini 1991), Croatia ( Lovašen-Eberhardt 1997), Romania ( Cristofolini 1991), Slovakia ( Holub and Bertová 1988), Poland ( Heywood and Frodin 1968; Danielewicz 2020). Reported from Moldova ( Heydemann 1986), but no specimens were seen by us from this country and its presence is considered unlikely. The records from the Balkans, Romania and Hungary include other related taxa and may be unreliable. The records from Belarus belong to C. lithuanicus . The records from Ukraine ( Tzvelev 1987) belong to C. lithuanicus and C. polonicus . Most of the records from Poland Zieliński (1975) belong to C. cinereus and C. polonicus .

Ecology.

The species occurs in dry meadows among pine and oak mountain forests.

Chromosome counts.

2n = 48 ( Dvořák and Dadákova 1976; Dvořák 1977); material from native populations collected in Czech Republic; vouchers at BRNU. The diploid counts (2n = 24) reported by Zieliński (1975) belong to C. polonicus . The tetraploid counts 2n = 48 reported by Zieliński (1975) belong to C. cinereus . The tetraploid counts 2n = 48 ( Pogan et al. 1990), based on material from native populations collected in Poland, may belong to the same species (vouchers at KRAM, not controlled).

Notes on nomenclature.

The herbarium collections of Jacob Christian Schaeffer may be kept at REG. So far, the only, but unambiguous original element available to us is the illustration in the protologue.

Notes on taxonomy and distribution.

Before Kreczetowicz (1940), this species was treated very broadly to include many species of this group in Eastern Europe. Tzvelev (1987) and Semerenko (1999) still circumscribed this species too broadly, with the inclusion of C. lithuanicus which differs from C. ratisbonensis by its taller stems and shorter (up to 0.8 mm vs. 0.8-1.4 mm long) pubescence. Zieliński (1975) and Skalická (1995) treated C. ratisbonensis broadly, including plants with taller stems (up to 50 cm long) and larger flowers (calyx 10-13 mm long), which apparently belong to C. lithuanicus and C. cinereus . Holub and Bertová (1988) also included C. ruthenicus in this species. With exclusion of C. polonicus , C. ratisbonensis is treated as absent from Eastern Europe. It is retained in the present synopsis for the purposes of comparison.