Orobanche gamosepala Reut.

Piwowarczyk, Renata, Pedraja, Óscar Sánchez, Khutsishvili, Manana & Kharazishvili, Davit, 2023, Holoparasitic Orobanchaceae in Georgia (Caucasus): taxonomic revision, diversity, distribution, habitats and host range, Phytotaxa 604 (1), pp. 1-103 : 42-44

4. Orobanche gamosepala Reut. in Candolle (1847: 15)

. Type:— RUSSIA (lectotype designated by Piwowarczyk et al. 2019: 54): North Caucasus, Stavropol Krai, near Pyatigorsk, “pr. Karass [colony two miles away from Mount Beshtau] & in m. Maschuka [Mashuk / Maschuka mountain], majo, Fl. Caucasica, [leg. Hohenacker]” (P02968131! [two righthand specimens (herb. Dr. a Ķhlewein)]); isolectotypes: P02968131! [only one specimen on left side of the sheet (herb. Al de Bunge)], G, LE [s.n., today LE01013898, LE01013900, LE01013899, LE01015360], COI00056887 - herb. Ķhlewein! Homotypic synonyms:— Ceratocalyx reuteri Lange (1864: 52) . Heterotypic synonyms:— Orobanche phoenicea Fisch. ex Beck (1890: 154) , pro syn. ( Turland et al. 2018: Art. 36.1b); Necranthus orobanchoides Gilli (1968: 297) . Fig. 26 .

General distribution: —the Caucasus, mainly in Ciscaucasia (European Russia), less abundant in Transcaucasia ( Georgia, Armenia, Azerbaijan and NE Turkey). Endemic to the Caucasus.

Distribution: —High mountain ranges of the Greater Caucasus mainly in the northern parts (Samegrelo-Zemo Svaneti and Racha-Lechkhumi and Kvemo Svaneti provinces, as well as Abkhazia and South Ossetia), and rarely in the central parts of the Lesser Caucasus (Samtskhe-Javakheti prov.). Needs confirmation in Adjara ( Fig. 27 ).

Habitat: —Here, in subalpine meadows, the upper mountain belt, rocky, grassy slopes, screes, shrublands, forests, usually (1700)2000–2600(2900) m.

Hosts: —In Georgia, it parasitises Geranium sp. (Geraniaceae) , such as G. gracile Ledeb. (probably a new host for it ( Sánchez Pedraja et al. 2016 +)), G. gymnocaulon DC. , G. ibericum Cav. , G. psilostemon Ledeb. (probably a new host for it ( Sánchez Pedraja et al. 2016 +)), and G. sylvaticum L.

Phenology: —Flowering (end May) June–July (August), fruiting end July–August.

Conservation status: —Near Threatened (NT). Species is known to occur in fewer than 20 localities and subpopulations are fragmented and do not consist of numerous individuals. EOO is ca. 25,000 km 2 and AOO is less than 200 km 2. Limiting factors are restricted loss/degradation of habitats as a result of overgrazing, felling of trees, landslides.

Taxonomic notes: — O. gamosepala ( Orobanche sect. Gamosepalae Teryokhin (1993: 40)) is genetically very distinct, forming a clade with O. anatolica / O. colorata ( Orobanche subsect. Arcuatae Teryokhin (1993: 40) [ Orobanche sect. Orobanche ]), simultaneously this clade is one of the oldest lineages of Orobancheae ( Piwowarczyk et al. 2021a).

Beck placed the two species in his Orobanche trib. Galeatae Beck in Biblioth. Bot. 19: 134 [152] (1890), nom. invalid. ( Turland et al. 2018: Art. 37.6). Syn: ≡ Orobanche [unranked] Galeatae Beck in Halácsy & Braun, Nachtr. Fl. Nieder-Österr.: 125 (1882) ( Beck 1890: 152); ≡ Orobanche Grex Galeatae (Beck) Beck in Engl., Pflanzenr. 96: 222 (1930), nom. invalid. Based on genetic studies ( Piwowarczyk et al. 2021a), we think that the two species should be considered as a different subgenus (Gamosepalae) within the genus Orobanche . This new subgenus would contain the two sections based on the section (Gamosepalae) and subsection (Arcuatae) published by Teryokhin and placed by him in two different sections (Gamosepalae and Orobanche ). The first comprises a single species ( O. gamosepala ), while the second comprises two ( O. colorata and O. anatolica ) or one ( O. colorata ) if we consider them synonyms.

Orobanche subg. Gamosepalae (Teryokhin) Ó. Sánchez & Piwow. , comb. & stat. nov. ( Turland et al. 2018: Art. 5A.1 and 6.10).

Basionym: Orobanche sect. Gamosepalae Teryokhin in Opred. Zarazikhovykh Fl. SSSR (ed. L.Yu. Budantsev): 40 (1993).

Type Name: Orobanche gamosepala Reut. in DC., Prodr. 11: 15 (1847).

— Orobanche sect. Gamosepalae Teryokhin in Opred. Zarazikhovykh Fl. SSSR (ed. L.Yu. Budantsev): 40 (1993).

— Orobanche sect. Arcuatae (Teryokhin) Ó. Sánchez & Piwow. , comb. & stat. nov.

Basionym: Orobanche subsect. Arcuatae Teryokhin in Opred. Zarazikhovykh Fl. SSSR (ed. L.Yu. Budantsev): 40 (1993).

Type Name: Orobanche colorata K. Koch. in Linnaea 17: 291 (1843).

Specimens examined: — GEORGIA. Abkhazia: Abchasien: in Alpenwiesen an den Quellen des Flusses Seken [Sakeni River (Kodori Range)] (Alboff!)” ( Beck 1930: 226, sub O. gamosepala ); Azikhba Mt, 17 July 1981, Sh. Kvaratskhelia (BATU); Bzipi [Bzyp, Gagra district] range, Kosiro Mt., S slopes, 2000 m, 9 August 1930, R.I. Tetlev [Potlev?] (LE); Abkhazia, Ritsa Strict Nature Reserve, mountain Agura, Kamennaya Polyana tract, Ritsa relic national park, ca. 2400 m, subalpine meadow, 43°29′48.4”N, 40°44′38.0”E, 14 July 2017, M. Skotnikova [phot. https://www. plantarium.ru/page/image/id/553690.html]; Adjara: cited by Gagnidze (1999), need confirmation; according to Dmitryeva (1990) O. gamosepala is rare in Adjara [no herbarium sheets kept from Adjara at TBI, BATU, etc.]; Racha-Lechkhumi and Kvemo Svaneti prov.: ad font fl. Tskhenistskali, Laphuri, ac dextea vallis, in prat. subalp., 2150 m, 19 July 1978, K. Kimeridze & G. Arabuli (TGM60937); Shovi, alpine grasslands and screes near the tourist path Glola-Lake Udziro, 4 km S from the village, 42.6669000°N, 43.6569778°E, ca. 2200 m, 6 July 2017, K. Chytrý & V. Kalníková (BRNU); near the forest path, the trail to Udziro lake, 1.5–2 km S of Shovi village, 42°41’31”N, 43°40’04”E, 1950 m, 18 July 2018, R. Piwowarczyk (KTC); Samegrelo-Zemo Svaneti prov.: bei Dadiasch [Svaneti Range] und Latpar [Latpari Pass], 2100 m, (Akinfiew!) ( Beck 1930: 226, sub O. gamosepala ); Latpari [Latpari Pass], Svanetie, 13 July 2011, M. Kesl [phot. biolib.cz/en/taxonimage/id201833/?taxonid=784321]; Svaneti, in pratis alp. ad font. fl. Dewlura, loc. Schawlura, in vallis Čuberi [Chubersky Gorge], 2500 m, 10 August 1977, K. Kimeridze (TGM5951); Adishi N, 43°01’15.9”N, 42°54’58.8”E, [ca. 2690 m], 2 July 2019, Chew_on_my_cholla (phot., https:// www.inaturalist.org/observations/120156045); Mestia distr., SE of Tsaldashi, 43°1’29.513”N, 42°53’32.678”E, 43°1’27.880”N, 42°53’26.950”E, 2535 m, 18 Augst 2022, P. Novák, V. Sedláček, D. Szokala & G. Štětková (phot.); Localities difficult to determine: Samegrelo-Zemo Svaneti and Racha-Lechkhumi and Kvemo Svaneti provinces: in Swanetia [Svaneti] (Radde) ( Beck 1890: 155, sub O. gamosepala ); Mingrelien [Samegrelo/Mingrelia]: an den Quellen des Flusses Ingur[Enguri River], 2900 m, (Radde!); Swanetien[Svaneti](Radde!) ( Beck 1930:226, sub O. gamosepala ); Samtskhe-Javakheti prov.: Borjomi-Bakuriani-Akhalkalaki Highway, 2 km south from Bakuriani, 41°44’08.0”N, 43°30’33.0”E, [1750 m], 6 June 2005, C. Davidson [phot., floraoftheworld.org/taxon/flora/17592186258585]; by the road from Bakuriani to the Tskhratskaro pass [2454 m], edge of a deciduous forest, an overgrown subalpine meadow, 41°43’52.2”N, 43°30’10.7”E, 1780–1790 m, 13 June 2022, R. Piwowarczyk (KTC); South Ossetia: subalpine meadow, on the eastern slope of the Bibility range [the Malaya Liakhva River basin], 2300 m, 11 July 1930, E. & N. Busch (LE); Ermani, in birch forest, near Dzoar-Shad Lake, on Geranium sylvaticum , 2 July 1937, I. Abramov (LE); birch forest, left slope of upper Ermani gorge, 2500 m, 4 July 1940, det. N. Tzvelev, (LE); left bank of the Upper Ermani, 17 July 1940,?, det. Tzvelev (LE); Бриттатское ущелье [Britat gorge], left slope, Haranasar урочище [Haranasar tract], 2 August 1929, E. & N. Busch (LE); Ermani, in a birch forest, left bank of the Middle Ermani gorge, 2200 m, 28 July 1939, E.E. Rut (LE); Шуацхури [Shuatskhuri; Bass. Maloi Liakhvy], hay mowing subalpine meadow, Nekh Mt., 2200 m, 9 July 1930, E. & N. Busch (LE); Ermani area, right bank of the Sredne-Erman gorge, subalpine meadow, on roots of Geranium ibericum , 12 July 1939, V.D. Mozgova (W1941-0003773; Ex Herb. Inst. Bot. Ac. Sc. URSS).

Figures

FIGURE 26. Orobanche gamosepala.A–E.General habit.F–G.Flower, side view.H.Flower,front view.I–J.Host, Geranium psilostemon. A, C, D. Representative habitats (Samtskhe-Javakheti prov., near Bakuriani). Photos by R. Piwowarczyk.

FIGURE 27. Distribution of Orobanche gamosepala in Georgia.