Centaurea gudrunensis Boissier & Haussknecht

Negaresh, Kazem & Rahiminejad, Mohammad Reza, 2018, A revision of Centaurea sect. Cynaroides (Asteraceae, Cardueae-Centaureinae), Phytotaxa 363 (1), pp. 448-450 : 448-450

13. Centaurea gudrunensis Boissier & Haussknecht in Boissier (1875: 673). Type:— IRAQ. Prov. Sulaymaniyah: in graminosis Pir Omar Gudrun , ca. 1200 m, June 1867, Haussknecht s.n. (holotype G!, isotypes K!, W!). ( Fig. 29 )

Biennial herbs, whole plant usually pale green, 25–50 cm tall; collar of fibrous petiolar remains present at stem base. Stem ascending, branced from near base to median part, branches with several heads, 3–4 mm in diam. at base, whitish, with thin yellow striations, lower part glabrous, other parts subglabrous or sparsely covered with long hirsute-articulate hairs. Leaves rigid (on drying), divided, scabrous or covered with short hirsute hairs, sometimes denser along midrib and veins. Basal and lower cauline leaves petiolate, lanceolate in outline, 20–30 × 4–5 cm, pinnatipartite or sublyrate; segments 3–6 pairs, lanceolate or oblong-linear, equal in size, sometimes terminal ones slightly larger, entire or with a single tooth or several coarse teeth; sometimes with a few additional smaller lobes in the intervals. Median cauline leaves sessile, 8–14 × 2–4 cm, pinnatisect or sublyrate; segments 2–3 pairs, narrowly lanceolate or oblong-linear, sometimes terminal segments larger and triangular with a single tooth or several coarse teeth; sometimes undivided, oblong or lanceolate, decurrent, up to 20 mm along stem, acute at apex. Upper cauline leaves smaller, sessile, undivided, lanceolate or lanceolate-linear, 1–6 × 0.25–1.2 cm, narrowly decurrent, entire, acute or acuminate at apex. Capitula numerous, arranged in a dichasium or loose panicle. Involucres ovoid or ovoid-oblong, truncate at base, 15–20 × 10–15 mm. Phyllaries multiseriate, coriaceous, imbricate, yellowish-green, smooth, loosely tomentose. Appendages rigid, concealing part of phyllaries only, triangular, straw-coloured, not decurrent, ca. 2 mm wide at base (excluding cilia), gradually narrowed into a 3–8 mm spine; cilia patent, 3–4 on each side, 2–3(–4) mm long; spines slightly longer than adjacent cilia. Outer phyllaries broadly triangular, 1.8–2.5 × 1.8–2.2 mm, appendages 3–6 mm long (including spine). Median phyllaries broadly lanceolate, 4–10 × 3–4 mm, appendages 8–13 mm long (including spine). Inner phyllaries narrowly lanceolate to linear, ca. 10 × 2.5–3 mm, appendages lacerated into a short spine or rounded with a denticulate margin. Flowers yellow; central florets hermaphroditic, 18–20 mm long, corolla 8–10 mm long, 5-lobed, lobes ± 4 mm long; peripheral florets sterile, slightly shorter than central ones, numerous (more 10 in each capitulum) and conspicuous, finely dissected, not radiant, 5-lobed, limb lobes filiform. Achenes oblong, 5–6 mm long, 2.2–2.6 mm wide, white and shiny, or grayish, smooth, glabrescent; insertion areole lateral, yellow, ca. 0.8 mm long. Pappus persistent, multiseriate, scabrous, pale brown, 4–6 mm long, inner rows as long as or even slightly longer than others.

Nomenclatural notes: —When describing Centaurea gudrunensis, Boissier & Haussknecht in Boissier ( Boissier 1875) cited one collection, Haussknecht s.n., as a type. In Flora Iranica, Wagenitz (1980) selected the specimen “ Haussknecht s.n.” as a lectotype that deposited at the herbarium G, but in 1960 and 2006 he selected another specimen as a lectotype, i.e. “ Haussknecht 585 ” that is deposited at the herbarium G; this collection number is not mentioned in Boissier treatment’s ( Boissier 1875). This paradox can be explained by three sheets that are at the herbarium G: two sheets numbered 585 and another one unnumbered. Therefore, Wagenitz (1960, 2006) should not have selected the specimen Haussknecht 585 as a lectotype because the protologue ( Boissier 1875) cited explicitly only Haussknecht s.n. For this reason, the lectotypification by Wagenitz (1960, 1980, and 2006) should be rejected, and since there is only one specimen Haussknecht s.n., it must be considered as a holotype.

Regarding the authorship of the name, Index Kewensis, IPNI and Wagenitz (1960) misinterpreted it as Centaurea gudrunensis Boiss. & Hausskn. ex Boiss. The species was described for the first time in Boissier’s Flora Orientalis ( Boissier 1875) . When the authorship was shared, Boissier wrote both authors in brackets as C. gudrunensis (Boiss. & Haussk.) (Fl. Orient. 3: 673) that should be interpreted as C. gudrunensis Boiss. & Hausskn. in Boiss., but certainly not as C. gudrunensis Boiss. & Hausskn. ex Boiss. (Art. 46.2).

Taxonomic and distribution remarks: — Centaurea gudrunensis is a narrow endemic to Sulaymaniyah Province, NE Iraq ( Fig. 30 ). It is an Irano-Turanian element, and grows on dry waste at foothills, grassland, Quercus forest, and mid-montane zone, at elavations of 1000–1200 m. Centaurea gudrunensis is the only species of C. sect. Cynaroides that is endemic to Iraq and so far only known from four gatherings in the area of Sulaymaniyah. Recently, Akhani (2004) reported this species from Ilam Province as new to Iran, but Negaresh & Rahiminejad (2015b) rejected this record that actually belongs to C. iranshahrii .

Centaurea gudrunensis is similar to C. iranshahrii in the shape of involucres and inflorescence and color of flowers. However, it differs from C. iranshahrii by its stem 25–50 cm (vs. 50–150 cm) tall, branched nearly from base to median part, glabrous or sparsely hirsute-articulate (vs. branched from median to upper parts, with divaricated branches, glabrous, sometimes upper part ± loosely arachnoid), indumentum of leaves scabrous or shortly hirsute (vs. leaves in juvenile phase scabrous with loosely arachnoid hairs and sessile punctate glands, in mature phase subglabrous and scabrous along margins), basal leaves pinnatipartite or sublyrate, 20–30 × 4–5 cm (vs. undivided, sometimes lyrate, 35–70 × 8–20 cm), lower and median cauline leaves pinnatisect or pinnatipartite, sometimes sublyrate (vs. undivided), involucres 15–20 mm (vs. (20–) 25–30 mm) long, appendages triangular (vs. elongate triangular), median appendages 8–13 mm (vs. (10–)12–20(–22) mm) long, cilia 3–4 on each side, 2–3 mm long (vs. 4–6 on each side, 2–5 mm long), and also pappus 4–6 mm (vs. 7–9 mm) long.

This species is also related to C. geluensis , especially because of involucres ovoid, stem color whitish and flowers yellow. However, it differs from C. geluensis by its stem 25–50 cm (vs. 45–60 cm) tall, lower cauline leaves pinnatipartite or sublyrate, segments 3–6 pairs (vs. basally lobed, with 3–4 lobes on each side, or lyrate), median cauline leaves 8–14 cm long, pinnatisect or sublyrate (vs. 4–8 cm long, undivided), involucres 15–20 × 10–15 (vs. 30–35 × 18–25), appendages concealing part of phyllaries only, triangular, ca. 2 mm wide at base (excluding cilia) (vs. totally concealing phyllaries, ovate-triangular or lanceolate, 5–7 mm wide at base (excluding cilia)), cilia 3–4 on each side, 2–3(–4) mm long (vs. 7–12 on each side, (1–) 1.5–2 mm long), flowers 18–20 mm (vs. 25–27 mm) long, achenes 5–6 mm long, 2.2–2.6 mm wide, white, insertion areole ca. 0.8 mm long (vs. ca. 7–7.5 mm long, ca. 3 mm wide, silver-bronze, sometimes dark brown to blackish, insertion areole ca. 1.8 mm long), and also pappus 4–6 mm (vs. ca. 3.5–4 mm) long.

Chromosome numbers: —Unknown.

Selected specimens examined:— IRAQ. Prov. Sulaymaniyah: in graminosis Pir Omar Gudrun , ca. 1200 m, June 1867, Haussknecht 585 ( G!: two sheets, JE!) . Sulaymaniyah, dry waste at foothills of mountain near city of Sulaymaniyah, 24 June 1957, Haines 1313 ( E!, K!) ; between Surdash and Shadala, Quercetum persicae, ca. 1000 m, 19 September 1933, Zohary & Feinbrun s.n. ( HUJ!) ; Bida Magrun, Anon 5208 ( K!) .

Figures

FIGURE 29. Centaurea gudrunensis Boissier & Haussknecht (Haussknecht s.n., G).

FIGURE 30. Distribution of Centaurea gudrunensis (circles), C. haradjianii (squares), and C. haussknechtii (triangles).