Cistanche tubulosa

Aldughayman, Majed, Thorogood, Chris J. & Hawkins, Julie A., 2024, Neotypification of Cistanche tubulosa (Schenk) Wight ex Hook. f.: a name applied to a widely distributed, polyphyletic group of plants, Phytotaxa 633 (1), pp. 9-16 : 12

Cistanche tubulosa - nomenclature

Joseph August Schenk described Phelypaea tubulosa in 1840 based on a specimen collected by Johannes Rudolf Roth and Michael Pius Erdl during an expedition with Gotthilf Heinrich von Schubert to Arabia Petraea from 1836- 1837 (a region comprising the former Nabataean Kingdom in Jordan, the Sinai Peninsula and north-western Arabian Peninsula). The transfer of P. tubulosa to genus Cistanche is attributed differently in various treatments, as Cistanche tubulosa (Schenk) Wight ex Hook. f. or as Cistanche tubulosa (Schenk) Hook. f. , both citing the Flora of British India 4: 324 (1885) as the place of publication. The name ‘ Cystanche tubulosa’ (his orthographic variant of Cistanche ) was used by Wight to accompany his plate 1420 for volume 4 of Icones plantarum Indiae Orientalis: or ‘figures of Indian plants’ ( Wight, 1850); there the name Cystanche tubulosa , with the initials RW, appeared below the plate but above the name ‘ Phelipaea lutea’ (his orthographic variant of Phelypaea ). In that same volume, Wight referred to his original reasons for considering this plate to represent the genus Cystanche as distinct from Phelipaea . However, he goes on to explain that this distinction, based on a ‘want of hairs’ in the corolla tube, was likely a draftsman’s oversight ( Wight, 1850, pp5). Having seen more material, Wight was convinced that the material he had seen was not distinct from Phelipaea lutea . Despite Wight’s doubts, Cistanche tubulosa Wight was subsequently recognised by Hooker in volume 4 of the Flora of British India (1885). It was Hooker, in this treatment, who made explicit the relation between Schenk’s species, which he referred to as Phelipaea tubulosa , and the name used by Wight, since he put the name Phelipaea tubulosa in synonymy under the name Cistanche tubulosa Wight. It seems unlikely that Wight was aware of Schenk’s treatment, since no mention of the basionym is provided by Wight, who gave his initials after his use of his new name. Schenk’s Phelypaea tubulosa is the basionym and if Wight’s use of the name was not a new combination we have Cistanche tubulosa Wight Icon. Pl. Ind. Orient. 4: t. 1420 (1850), non Phelypaea tubulosa Schenk, Pl. Spec. Schubert : 23. Confusion about Wight’s use of C. tubulosa might explain the persistence of the name Cistanche tubulosa (Schenk) Hook. f. The International Plant Names Index (IPNI) accepts Cistanche tubulosa (Schenk) Wight ex Hook. f. as the validation of Wight’s name. Whatever Wight’s intention, his plate 1420 cannot serve as a type for Cistanche tubulosa . Rather, a specimen seen by Schenk from the Roth and Erdl expedition should serve as the type.

The specimen cited by Schenk was collected ‘ad viam inter Suez et Tor in Arabia petraea’, in the month of February. According to Stafleu and Cowan (1976), Schenk was employed as extraordinary professor of botany (1844) and then as regular professor and director of the Botanic Garden of Würzburg University (1886-1868). He was later (1868-1887) employed in Leipzig. Schenk’s herbaria at WB and LZ were both destroyed. Other specimens of Schenk’s are reported by Stafleu and Cowan (1976) to be at BR, C, GOET. MW, REG, W and WAG. Ataei (2017) reported that no type specimen exists at REG (Peter Poschlod, pers. comm. to Ataei 24 August 2014), W (Armin Löckher, pers. comm. to Ataei 16 August 2014), BR (Sofie De Smedt, pers. comm. to Ataei 25 August 2014) or WAG (Jan Wieringa, pers. comm. to Ataei 05 September 2014). Schenk may have examined material now held elsewhere; a specimen collected by Erdl and Roth is in M but the specimen is missing (pers. comm. to Aldughayman, 18 September 2018). According to the Flora of the USSR, the type was in Oldenberg ( Germany) but correspondence from LMO states that the herbarium holds just one specimen of Egyptian Orobanchaceae (Kay Fuhrmann, pers. comm. to Lei 4 June 2018). The specimen was given to the museum by the son of the Grand Duke of Oldenburg, Friedrich August, in 1876; he made the collection during his voyage to the eastern Mediterranean and Egypt. Thus, the Flora of the USSR seems to be in error, and since an exhaustive search has not since uncovered the specimen, it seems the type specimen of C. tubulosa is indeed missing or destroyed.