Senecio olgae Regel & Schmalhausen

Calvo, Joel, Álvarez, Inés & Aedo, Carlos, 2015, Systematics of Senecio section Crociseris (Compositae, Senecioneae), Phytotaxa 211 (1), pp. 448-450 : 448-450

26. Senecio olgae Regel & Schmalhausen in Regel (1882: 45). TYPE: Tajikistan, Sughd, Basmanda ravine, [39º39'N 69º08'E], 1 June 1870, O . A . Fedtschenko s.n. (lectotype, designated here, LE!) .

Senecio akrabatensis Franchet (1883: 312) . TYPE: Uzbekistan, passe d'Akrabat , [38º18'N 66º37'E], 24 Abr 1881, G. Capus 649 (lectotype, designated here, P-3729618 image!; isolectotype, P-3729614 image!).

Senecio sarawschanicus Winkler (1895: 153) . TYPE: Tajikistan, Sughd, Kschtut , [39º27'N 68º03'E], May 1892, V . L . Komarov s.n. (lectotype, designated here, LE!) .

Perennial herb. Rhizome ca. 4 cm long, ca. 1.2 cm in diam., ± horizontal, with swelled fastigiate roots. Stem 33–71 cm, erect, leaved, corrugated, solid, not ramificated, weakly arachnoid (increasing towards the base), sometimes glabrescent, base without remnants of old leaves or tufts of hairs. Basal leaves 6.5–12.3 cm long, 4.5–10 cm wide, ± persistent, usually withering early, deltate to lyrate, sometimes broadly ovate (ratio basal leaf width / basal leaf length = 0.56–1.18), obtuse, truncate to cordate, with a petiole 5.8–17 cm long, irregularly dentate, often deeply lobed at the base, glabrescent to covered with scattered trichomes, particularly beneath (trichomes 0.3–0.6 mm long), concolorous. Cauline leaves 4–8; middle cauline leaves 6.4–16.2 cm long, 4.3–9 cm wide, alternate, deltate to lyrate, rarely broadly lanceolate (ratio middle leaf width / middle leaf length = 0.28–0.88), acute to obtuse, amplexicaul-auriculate to cordate with a petiole up to 10 cm long, irregularly dentate, often deeply lobed at the base, glabrescent to covered with scattered trichomes, particularly beneath, tertiary venation inconspicuous; upper cauline leaves 1.8–8.6 cm long, 0.8–4 cm wide, broadly lanceolate (ratio upper leaf width / upper leaf length = 0.16–0.88), acute, amplexicaul, rarely sessile, dentate (teeth 1–5 mm deep) to subentire, glabrescent to covered with scattered trichomes. Synflorescence 5–21 cm long, corymbose to pseudocorymbose, with linear-oblong bracts. Capitula (1–)4–6(–10), 37.2–38.8 mm in diam.; involucre 12.8–27.3 mm in diam., 11–15 mm long, cupuliform; involucral bracts (13–)16–19(–22), 9.4–13.6 mm long, 1.7–4 mm wide, with scarious margin 0.4–0.9 mm wide, ensiform, attenuate, usually smooth or nearly so, apex rarely with a faint black spot, glabrescent to covered with scattered arachnoid trichomes (trichomes 0.2–0.8 mm long); supplementary bracts (3–)4–6(–8), 4.2–8.8 mm long, 0.4–0.6 mm wide, subulate, without scarious margin, a third to two thirds as long as involucral bracts, glabrescent to covered with scattered arachnoid trichomes (trichomes 0.2–0.8 mm long), not imbricated. Ligulate florets ca. 10, 22.4–32.5 mm long, yellow; tubular florets 8.9–11 mm long, 0.8–1.6 mm in diam., yellow. Achenes 7.6–9.8 mm

SYSTEMATICS OF SENECIO SECTION CROCISERIS

Phytotaxa 211 (1) © 2015 Magnolia Press • 81 long, 1.4–1.8 mm wide, subcylindrical (ratio achene width / achene length = 0.17–0.21), shorter than pappus (ratio achene length / pappus length = 0.64–0.97), with 12–17 ribs, with trichomes 0.11–0.29 mm long covering ± the whole surface; pappus 9.8–13.6 mm long, whitish. Chromosome number: unknown.

Distribution and habitat: — Tajikistan, Turkmenistan, Uzbekistan; rocky slopes, clay slopes, steppe meadows, shrubs with Juniperus and Pistacia , woods of Acer ; elevations of 900–2400 m ( Figure 31 ).

Phenology: — Flowering from April to July.

Etymology: — Senecio olgae is named in honor of Olga Aleksandrovna Fedchenko (1845–1921), Russian botanist and explorer of Central Asia.

Discussion: — Senecio olgae is distinctive because of its large deltate to lyrate basal leaves and often amplexicaul-auriculate cauline leaves. It is variable in the leaf shape; its forms with broadly ovate basal leaves may be confused with S. franchetii (see comments under it). Another similar species from Central Asia is S. paulsenii , which has its basal leaves oblanceolate to lanceolate, subentire to sinuate (teeth becoming larger towards the lamina base). As already commented, S. olgae usually bears characteristically deltate to lyrate leaves. Other useful characters to discriminate each other are the supplementary bracts [(5–)6–9(–14) in S. paulsenii vs. (3–)4–6(–8) in S. olgae ], and the base of the stem (with tufts of hairs and remnants of old leaves in S. paulsenii vs. no remnants of old leaves in S. olgae ). These species are allopatric.

The cordate basal leaves and the amplexicaul-auriculate cauline leaves are distinctive characters among the Crociseris species, only displayed by S. olgae , S. trapezuntinus , and S. perralderianus , the species that are geographically far away from each other. The comments to distinguish them are under the respective species.

Despite no isolectotypes have been located, there are four syntypes kept at LE and another one at US .

Selected specimens examined. TAJIKISTAN. Districts of Republican Subordination: the Varzob river , bridge to Puguz, 38º51’N, 68º51’E, 1932, B. A . Fedtschenko 449 ( LE); systema fluminis Varzob, right bank of the Varzob river , 35km to the north of Dushanbe, 38º49’N, 68º49’E, 23 May 1957, J. S . Grigorjev 117 ( LE); The Gissar Range, valley of the Varzob river, upper Khusher qishlaq, 38º58’N, 68º45’E, 20 May 1937, A. I . Vvedensky 68 ( LE). Sughd: north slope of the Turkestan Range , near source of the Kusavli-say, 39º34’N, 68º36’E, 19 June 1970, R. V . Kamelin 196 ( LE); Schink , 39º26’N, 67º56’E, 29 May 1892, V. L . Komarov s.n. ( LE, US) ; north slope of the Turkestan Range, Kusavli-say, lower part, west slope, 39º38’N, 68º41’E, 3 June 1958, A . Konnov 1020 ( LE) . TURKMENISTAN. Lebap: Road from Toychi to Kugitang qishlaq, near Kurgan-Tash lake , 37º55’N, 66º28’E, 13 Apr 1958, A. I . Vvedensky, S. S . Kovalevskaya & O. V . Tscherneva 115 ( LE) . UZBEKISTAN. Djizak: The Turkestan Range, Sanzar river basin, Zaaminskaya forest dacha, source or the [Naychey] river, 39º38’N, 68º33’E, 17 July 1934, I. G . Protopopov & P . Gomolitsky 228 ( LE); The Pamir-Alay, the Turkestan Range, the Gurgalash river basin, pass to Zarafshan valley , on the way to [Urmitai] qishlaq, 39º41’N, 68º14’E, 18 June 1935, V . Zakrzhevsky 465 ( LE). Qashqadaryo: south-east of Yakkabag, hills between Khusyn qishlaq and the Tynis-dara river , 38º48’N, 66º58’E, 15 May 1979, R. V . Kamelin & Mamedov 147 ( LE); Ak-su river, opposite Merake village , 39º1’N, 67º7’E, 15 May 1947, E. E . Korotkova 296 ( LE); Ak-su river, opposite Merake village , 39º1’N, 67º7’E, 15 May 1977, E. E . Korotkova 327 ( LE). Samarqand: near Urgut village, Alayaron mountains , Tash-issyk track, 39º21’N, 67º13’E, 13 May 1979, R. V . Kamelin & Mamedov 53 ( LE); north slope of the Zarafshan range, Aman-kutan , 39º19’N, 66º57’E, 25 Apr 1913, A. I . Michelson 1040 ( LE). Surxondaryo: Chul’bair mountains , near Sina qishlaq, Kyzkurgan hill, 38º22’N, 67º39’E, 30 May 1973, V. P . Botschantzev 145 ( LE); South Tajikistan, Babatag mountains, near mount Zarkasa , 10 km from Akmechet’, 37º59’N, 68º10’E, 27 Apr 1986, R. V . Kamelin, B . Ganibal & L . Averyanov 230 ( LE); Turkestania, The Emirate of Bukhara, Baysun Principalitie , Buzgala canyon, 38º13’N, 67º11’E, 30 Apr 1897, S. I . Korshinsky 208 ( LE) .

Figures

FIGURE 31. Distribution map for Senecio franchetii Winkler (●), S. olgae Regel & Schmalhausen (∆), and S. paulsenii Hoffmann subsp. paulsenii (○).