Orobanche alba Stephan ex Willdenow (1800: 350)

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 : 53-55

8. Orobanche alba Stephan ex Willdenow (1800: 350)

. Type:— RUSSIA (lectotype designated by Piwowarczyk et al. 2019: 67): 1. “ Or. alba 3 [in Sibiria versus Mare Caspium (Caspian Sea, North Caucasian Federal District)], Rchb. fil.”. ‒ 2. “Rchb. Icones ... Me judice hic est Typus vera O. alba ex ... Willdenowianii [m. Reichenbach f.]”. ‒ 3. “ Orob alba Steph. An ab auctore? … Or albae Steph. ... det. Dr. G. Beck [m. Beck]”. – 4. “214 W”. (B-W11600-030!). Heterotypic synonyms:— O. epithymum DC. in Lamarck & Candolle (1805: 490) ( Piwowarczyk et al. 2019: 67); O. glabrata C.A. Mey. in Eichwald (1831: 16); O. grigorjevii Novopokrovsky (1950: 326) ; O. alba subsp. xanthostigma Rätzel & Uhlich (2004: 198) ; O. epithymum var. major Čelak. (1871: 341) . Fig. 34 .

General distribution: —It is widely distributed, from Europe and eastwards to Asia Minor, the Caucasus, Central Asia, and the Himalayas.

Distribution: —Scattered localities in almost all regions of the country ( Fig. 35 ).

Habitat: —Rocky slopes, subalpine meadows, edges of forests and shrublands, mixed forests, roadsides, steppe communities, ruderal communities, usually (500)1100‒2400(2600) m.

Hosts: —Only on Lamiaceae , usually on Thymus sp. , like T. collinus Salisb. [ T. vulgaris L. subsp. vulgaris ], T. coriifolius Ronniger [ T. sosnowskyi Grossh. ], T. marschallianus Willd. [ T. pulegioides subsp. pannonicus (All.) Kerguélen ], T. nummularius M. Bieb. , T. sipyleus Boiss. [ T. rariflorus K. Koch ], T. transcaucasicus Ronn. , and Origanum vulgare L., rarely Salvia and Ziziphora sp.

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

Conservation status: —Least Concern (LC). The species has a rather wide distribution in Georgia. EOO is 55,000 km 2 and AOO is ca. 3000 km 2. The most common threats are related to habitat degradation, overgrazing and overgrowing.

Taxonomic note: — Orobanche glabrata was described from Kachetia [Kakheti, Georgia] by C.A. Meyer in Eichwald (1831: 16), this taxon was treated in the same way (at the species rank) by Reuter (1847: 33) and ( Boissier 1879: 511). Later, Beck (1890: 212) placed it as a “forma” of O. alba , but in (1930: 154) raised it to the rank of a “varietas” of the same species and indicated that he had seen the original material in the LE herbarium (“herb. Ledebour in collectionibus St. Petersb.”). Subsequently, ( Tzvelev 2015: 204) treats it as a different species but within its O. alba aggr. and designates the original material mentioned by Beck (“in herb. Ledebour in collectionibus St. Petersb.”) as the lectotype of this species (“LE” [s.n.]), but we consider this typification of Tzvelev to be second-step ( Turland et al. 2018: Art. 9.17), because in LE, we can observe two sheets of original material, today numbered, LE01015393 and LE01015394. Below, we complete this typification.

Orobanche glabrata C.A. Mey. in Eichw., Pl. Casp. 1: 16[–17] t. 17 (1831)

Ind. loc.: “Hab. in Kachetia [Kakheti, Georgia]” ( Eichwald 1831: 16); “Vidi originalia in Kachetia lecta (l. Eichwald) in herb. Ledebour in collectionibus St. Petersb. [LE - Herbarium Petropolitanum]” ( Beck 1930: 154, sub O. alba var. glabrata ).

Lectotype (Tzvelev, hic designatus ( Tzvelev 2015: 204)): ́In Transcaucasiae ditione Kachetia, Eichwald» (LE) ( Turland et al. 2018: Art. 9.17 [first-step]). 1. “ Orobanche glabrata mihi! [m. C.A. Meyer]”. – 2. “I. Novopokrovsky. Notae criticae / Orobanche glabrata C.A. Mey. / specimen authenticum! / ́Hab. in Kachetia [Kakheti, Georgia]» / Eichw., pl. nov. casp. p. 16 / 1949.12.IX”. – 3. “= O. alba Steph / 1955.II.28 Teste: Tzvelev [m. Tzvelev]”. – 4. “ O. alba var. glabrata (Mey.) Beck [m. Beck]” (LE01015393 - http://re.herbariumle.ru/01015393 ( Turland et al. 2018: Art. 9.17 [second-step])). Isolectotype: 1. “Herb. Ledebour / Orobanche glabrata C.A. Meyer / In Kachetia & Imeritia [?] leg. Eichwald ”. – 2. “Herb. Ledeb. 758.24 / Orobanche glabrata C.A. Mey ”. – 3. “Ovarium glabrum ... 18.X.1949 I. Novopokrovsky”. – 4. “= O. alba Steph / 1955.II.28 Teste: Tzvelev [m. Tzvelev]” (LE01015394 - http://re.herbariumle. ru/01015394).

In addition, we indicated that Beck considered this taxon to be a synonym for the species ( O. hymenocalyx Reut. in DC. (1847: 20)) described by Reuter of the “ Georgiâ Caucasicâ prope Helenendorf [Goygol, Azerbaijan]”. In this same article ( Tzvelev 2015: 205), and within his O. alba aggr., he includes the O. grigorjevii Novopokrovsky (1950: 326) , a species described from Tajikistan which he considers to be a synonym for O. alba subsp. xanthostigma Rätzel & Uhlich (2004: 198) , apparently only on the basis of it parasitizing the same host-plant Origanum vulgare L. (host relatively common here). The last taxon was described from the Caucasian Republic of Adygea ( Russia) and their descriptors pay more attention to stigma colouration (yellow) than to the host. We, given the great variability of the species in our study zone, prefer to adopt a more synthetic treatment and include all the taxa mentioned within a single species (only parasitic on Lamiaceae ) ( Piwowarczyk et al. 2019: 67).

Specimens examined:— GEORGIA. Adjara prov.: distr. Shuakhevi, Ajara, vil. Tskhramukhli [Nigazeuli], pineoak forest, 29 April 2015, N. Memiadze (BATU); distr. Shuakhevi, Ajara, vil. Chanchkhalo, rocky slope, 29 April 2015, N. Memiadze (BATU) [as O. caryophyllacea ]; distr. Shuakhevi, Ajara, mount. Tbeti, subalpine stones, 18 August 2016, M. Darchidze & N. Memiadze (BATU) [as O. caryophyllacea ]; distr. Shuakhevi, vil. Gogadzeebi, rocky slopes, 2000 m, 7 Aug 1954, A. Dmytrieva (BATU) [as O. caryophyllacea ]; Imereti prov.: between Tkibuli and Kharistvala, steep slopes above road, near Nakerala pass, on Salvia , 42°23’01”N, 43°00’46”E, 1030 m, 16 July 2015, R. Piwowarczyk (KTC); S of Kharistvala, slopes below Nakerala pass, on Origanum , 42°22’35”N, 43°02’21”N, 1250 m, 17 July 2018, R. Piwowarczyk (KTC); Kakheti prov.: NW of Udabno, E of Jikurebi Lake, steppe hills, on Thymus , 41°34’12”N, 45°19’53”E, 860 m, 26 May 2014, R. Piwowarczyk (KTC); Sighnaghi NE, roadsides, edges of shrublands and forest, slopes above asphalt side road, near old defensive walls, N of the road to Tsnori, on Origanum , 41°37’30”N, 45°55’30”E, 700 m, 28 May 2014, R. Piwowarczyk (KTC); Sighnaghi NE, side path from main road to Tsnori, rocky slopes, shrublands, on Thymus and Origanum , 41°37.2’N, 45°55.8’E, 640 m, 13 May 2019, R. Piwowarczyk (KTC); W of Tetri Tsklebi, Gombori pass, steppe hills, on Origanum , 41°51’54”N, 45°17’09.3”E, 1590 m, 23 July 2015, R. Piwowarczyk (KTC); near Tusheti National Park, [N of Birkiani, 2600 m], 42°19’39.7”N, 45°19’48.6”E, 30 June 2012, Rbeunen [phot., https://www.inaturalist.org/observations/38703975]; Tusheti, Que and Old Omalo, 6 July 2023, K. Akopashvili (phot.); NW of Ujarma, road to the old sanatorium, clearings, roadsides, and forest edges in oak-hornbeam forests, dry meadows, on Origanum , 41°47’26.5”N, 45°09’02.2”E, 820 m, 2 June 2022, R. Piwowarczyk (phot.); Kvemo-Kartli prov.: prov. Tiflis, distr. Borčalo, in declivilatibus montii Jagludzha (range W of Rustavi], 6 June 1921, B. Schischkin (TGM53184) [as O. cumana by Melikischvili]; Kojori E, slopes by the asphalt road (Iunkeri Str.) [Yunkerebis Str.], forest edges, on Thymus , 41°39’37.7”N, 44°43’33.6”E, 1215 m, 6 June 2022, R. Piwowarczyk (phot.); Mtskheta-Mtianeti prov.: distr. Tianeti, fauc. Gusno [Qusno, Kusno gorge, the left confluent of the Iori River, ca. 42.087374°, 44.965573°], in decliv. siccis, 13 July 1960, Melikischvili (TGM11289) [as O. grossheimii by Melikischvili]; between village Saguramo S and Saguramo Range, 300 m east from St George Church, xerothermic shrublands, hornbeam forest edges, 41°53’26”N, 44°45’57”E, 690 m, on Origanum vulgare , 6 June 2014, R. Piwowarczyk (KTC); Mtskheta NW, slopes on the road to Shiomgvime monastery, on Thymus , 6 June 2014, 41°50’54”N, 44°41’37”E, 640 m, R. Piwowarczyk (KTC); Kartli, Shiomgvime, Fischer et al. (2018) [phot.]; between Mleta and Gudauri, slopes near main road, radsides, 16 July 2015, R. Piwowarczyk [phot.]; Zemo Mleta, pass, 4 July 2023, K. Akopashvili (phot.); SE of Karkucha vil., rocky slopes, subalpine grasslands and meadows, on Thymus , 17 July 2015, R. Piwowarczyk [phot.]; W of Stepantsminda (Kazbegi), below Gergeti Trinity Church, rocky slopes, subalpine grasslands,on Thymus , 42°39’41”N, 44°37’14”E, 2120 m, R.Piwowarczyk (KTC); Kudro, 41°56’28.6”N, 45°03’10.4”E, 10 June 2019, F. Riegel [phot., https://www.inaturalist.org/observations/29138700]; Mtiuleti, Dariali canyon [gorge], old road near tunel, 1400 m, Fischer et al. (2018) [phot., as O. teucrii ]; Mtskheta-Mtianeti, Great Caucasus, view point Mleta 2–3 km SE below Gudauri, 44°29’38’’E, 42°26’21’’N, 1800 m, 17 July 2002, G. Schneeweiss et al. (WU0027646, WU0027647); Mtskheta-Mtianeti, Great Caucasus, valley of small river Tibais-tskali near Gveleti, i.e. gorge of river Dariali, 44°37’28’’E, 42°42’29’’N, 1480–1600 m, 20 July 2002, G. Schneeweiss et al. (WU0027650, WU0027651, WU0027652, WU0027653); Prov. Chwei (Khevi, Chevi), Grosser Kaukasus (Kavkasioni, Ķavķasioni), T’ruso Schlucht (Trusos cheoba) 0.5–2.7 km WNW Zemo Ok’rokana (Zemo Okroqana), d.i. ca. 5–7.2 km WNW Kobi (Ķobi), 44°26’– 44°27’30’’E, 42°35’– 42°36’N, 2050–2100 m, 23 July 1997, G. Schneeweiss (WU0027676); Dusheti distr., the central part of the Greater Caucasus, subalpine meadow, on T. nummularius, Khada gorge, 42.48509°N, 44.53841°E, 1912 m, 4 September 2022, M. Khutsishvili et al. (phot.); Racha-Lechkhumi and Kvemo Svaneti prov.: W of Glola, slopes on the road, edges of forest, shrublands, 42°42’10”N, 43°36’34”E, 1225 m, on Origanum , not exluded also Teucrium and Salvia , 15 July 2015, R. Piwowarczyk (KTC); NE of Ambrolauri, between Mukhli and Kvemo Bari, before Kvemo Bari, slopes, on Origanum , 19 July 2018, R. Piwowarczyk [phot.]; Samegrelo-Zemo Svaneti prov.: between Mestia and Heshkili, forest roadside, near Heshkili Hut, on Origanum , 43°01’14”N, 42°42’08”E, 1760 m, 22 July 2018, R. Piwowarczyk (KTC); N of Cheliri (near Iskari), N of the tower, slopes, roadsides, edges of shrublands, 1600–1700 m, 23 July 2018, R. Piwowarczyk (KTC); Samtskhe-Javakheti prov.: Timotesubani, slope near monastery, on Origanum , 41°48’35”N, 43°31’03”E, 1150 m, 2 June 2014, R. Piwowarczyk (KTC); prov. Tiflis, distr. Gori, Borjomi, in silva prope Likani, 27 June 1920, B. Schischkin (TGM8425, right specimen) [as O. arenaria by Melikischvili]; Borjomi, July 2011, M. Podsiedlik (KTC); Abastumani, slopes above aphalt road, edges of forest, on Thymus , 41°43’39”N, 42°50’27”N, 1230 m, 12 July 2015, R. Piwowarczyk (KTC); between Abastumani and Zekari pass, side road, rocky slopes of Otskhe river, 41°47’07”N, 42°50’27”E, 1420 m, 12 June 2015, R. Piwowarczyk (KTC); between Zarzma and Utkisubani, slopes above road, on Origanum , 41°40’01”N, 42°37’25”E, 41°39’48”N, 42°36’39”E, 1400–1500 m, 13 July 2015, R. Piwowarczyk (KTC); between Utkisubani and Goderdzi pass, slopes above road, roadsides, on Origanum , 41°38’22”N, 42°35’16”E, 1630 m, 13 July 2015, R. Piwowarczyk (KTC); Aspindza distr., valley of the river Kura, at the mouth of the Ahalkalaki-chai river, steppe, rocky slopes on the right bank of the river Kura, 1500 m, on Ziziphora , 14 July 1960, N. Tzvelev & S. Cherepanov (LE); between Rustavi and Idumala, steppe hills, roadsides, slopes of the river Mtkvari, 41°35’36”N, 43°10’09”E, 1020 m, 3 June 2014, R. Piwowarczyk (KTC); SSE from Bakuriani Andesite, below Tskhratskaro pass, subalpine meadows, rocky places, on Thymus , 41°41’37”N, 43°31’00”E, 2340 m, 1 June 2014, R. Piwowarczyk (KTC); Borjomi Nature Reserve, W of Likani, 41°49’52.4”N, 43°19’16.5”E, 16 June 2019, C. Frasch [phot., https://www.inaturalist.org/observations/31416512]; by the road from Bakuriani to the Tskhratskaro pass [2454 m], below Tskhratskaro pass, roadside/subalpine rocky meadow, on Thymus , 41°42’06,0”N, 43°30’41,6”E, 2175–2230 m, 13 June 2022, R. Piwowarczyk (KTC); Bakuriani NW, rocky basalt slopes near the road to Borjomi, on Thymus , 41°45’34.1”N, 43°30’48.4”E, 1570 m, 15 June 2022, R. Piwowarczyk (phot.); Bakuriani NW, foot of the rocky basalt slopes near the road to Borjomi, on Thymus , 41°45’44.6”N, 43°30’16.4”E, 1600 m, 15 June 2022, R. Piwowarczyk (KTC); Chitakhevi SW, roadsides, slopes of the Mtkvari (Kura) river, on Thymus , 41°47’02.8”N, 43°17’40.4”E, 850 m, 17 June 2022, R. Piwowarczyk (phot.); between Dviri and Chitakhevi, NW from Chobiskhevi, slopes of the river Mtkvari (Kura), roadside and rocky slopes on a sharp bend of the road, on Thymus , 41°46’45.0”N, 43°17’40.1”E, 876 m, 41°46’40.7”N, 43°17’16.8”E, 888 m, 16 June 2022, R. Piwowarczyk (phot.); South Ossetia: Юго-Осетинский [South Ossetia] Горно-Луговой Стационар [Mountain-Lugovoi (meadow) Station], Академии наук СССР [Academy of Sciences of the USSR], под руководством Е.А. Буш. [under the leadership of E.A. Busch.], Cрмани [Gora Ermani] ... Субальпийский луг [Subalpine meadow] ... 2300 м над ур. моря, 15 July 1957, ВиТОЛЛО И.С. [Vitollo I.S.] (MW0723454, sub O. anatolica ); Tbilisi prov.: Gldani-Nadzaladevi district, between Chargali St. and Tbilisi Reservoir, dry grasslands and shrublands on slopes of the exposure south, southwest and northwest, 41°46’15”N, 44°48’17”E, 570 m, on Thymus , 25 May 2014, R. Piwowarczyk (KTC).

Figures

FIGURE 34. Orobanche alba. A–D. General habit. E–G. Flower, side view. H–I. Flower, front view. J–L. Representative hosts (J. Origanum vulgare. K. Thymus collinus. L. Salvia verticillata).

FIGURE 35. Distribution of Orobanche alba in Georgia.