Cytisus cinereus Host, Fl. Austriac.: 2: 343 (1831)

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

8. Cytisus cinereus Host, Fl. Austriac.: 2: 343 (1831)

- Cytisus ratisbonensis subsp. cinereus (Host) Jáv., Magyar Fl. 2: 609 (1924).

= Cytisus horniflorus Borbás, Balaton Fl.: 299 (1900), syn. nov. Type. Hungary. "In arenosis silvaticis ad Monor in Hung. centrali", 08.06.1887, V. Borbás (lectotype BP581457, designated by Pifkó (2005: 26)).

= Cytisus paczoskii V.I.Krecz. in Bot. Zhurn. SSSR 25: 261 (1940), syn. nov. - Chamaecytisus paczoskii (V.I.Krecz.) Klásk. in Preslia 30(2): 214 (1958). Type. Ukraine. Ternopol Region: "Silva prope pag. Kidancy (non procul stat. viae ferrariae Maximovka)", 26.04.1916, A.I. Michelson (holotype LE01024080).

Type.

Cultivation, originated from Hungary. "Ex Hort." [Botanical Garden at Belvedere in Vienna , now Botanical Garden of the University of Vienna], Hb. Host 4148 (lectotype W1885-4148, designated here: https://w.jacq.org/W18850004148). Fig. 8 .

Description.

Upright shrubs with erect, basally ascending stems up to 60(80) cm tall and long branches. Leaves with elliptic to obovate leaflets, glabrous above (the basal leaves are slightly hairy above), with appressed hairs 0.4-0.8(1.2) mm long below, petioles sparsely covered with laxly appressed hairs. Flowers strictly lateral, 1-4 in axils, on pedicels 3-5 mm long, yellow; calyx 11-14 mm long, with laxly appressed to subpatent hairs 0.6-1.2(1.5) mm long; standard subrbicular, glabrous or hairy above.

Distribution.

Europe: Austria, Slovakia, Serbia, Hungary, Romania, Poland, Ukraine ( Tzvelev 1987; Fedoronchuk 2022), Moldova ( Shabanova et al. 2014). As compared with the distribution area circumscribed by Tzvelev (1987), this species is new to Austria, Poland, Romania, Serbia, Slovakia and, due to the new synonymy, to Hungary. The only locality of this species previously reported from Moldova ( Kreczetowicz 1940; Tzvelev 1987) is actually situated in Ukraine (Odessa Region); its voucher has not been found ( Didukh 2009), but recent sources ( Shabanova et al. 2014) reported a wide occurrence of the species in steppic areas of Moldova. The occurrence in Slovakia is logically expected.

Ecology.

The species occurs in open places, meadows and forest margins on plains and slopes of hilly uplands, often on sandy or calcareous substrates.

Chromosome counts.

2n = 48 ( Zieliński (1975), as Cytisus ratisbonensis subsp. ratisbonensis ).

Notes on taxonomy and distribution.

Cytisus cinereus was described from sandy and forested areas of Hungary ( Host 1831) with a reference to " C. biflorus " in Waldstein and Kitaibel (1804). The latter work lists a few localities in central and eastern Hungary, which are the likely origin of the material cultivated in Vienna by Host. Both descriptions ( Waldstein and Kitaibel 1804: 181; Host 1831: 343) mentioned the oblong leaves glabrous above, a rather appressed pubescence on the calyx, and long erect branches. These characters agree with those of C. paczoskii ; Kreczetowicz (1940) distinguished his latter species from C. lindemannii (= C. elongatus ) on the basis of its glabrous standard (described as glabrous by Waldstein & Kitaibel, but stated as pubescent by Host).

Cytisus cinereus and C. horniflorus were distributed in the same exsiccatae as different taxa ( Anonymous 1919), but the plants are virtually identical.

Kreczetowicz (1940) described this taxon as a presumed hybrid between C. lindemannii (= C. elongatus ) and C. ratisbonensis . We consider it a stabile taxon with its own diagnostic characters and distribution area, clearly deserving the species rank. Some authors classified this species as an infraspecific taxon of C. ratisbonensis ( Jávorka 1924) or included it in the latter species ( Pifkó 2005, 2009b), from which it differs by erect branches, larger flowers on longer pedicels, and a longer and denser pubescence of the whole plant.

Skalická (1983) and Cristofolini (1991) correctly recognised C. paczoskii (= C. cinereus ) as a species close to C. ruthenicus , but different in a more developed pubescence. Due to the lack of material, they were not able to circumscribe its distribution.

In Poland, Zieliński (1975) identified plants of this species as C. ratisbonensis subsp. ratisbonensis , and so did Pifkó (2005, 2009b) in Hungary. For this reason, C. paczoskii (= C. cinereus ) was treated as endemic to Eastern Europe ( Tzvelev 1987). According to our data, its distribution includes the Pannonian Basin and the territories from the Podolian to Lesser Polish uplands.

Dubovik (2016) reported C. paczoskii as occurring in western Belarus. This record is based on a different interpretation of this species name, which Dubovik considered to belong to a presumed hybrid between C. ratisbonensis and C. ruthenicus . The plants identified as C. paczoskii by Dubovik largely belong to C. lithuanicus .

Figures

Figure 8. Lectotype of Cytisus cinereus Host.