Typification and characterization of Orobanche ritro Gren. & Godr. (Orobanchaceae) of central and southern Europe

Figures & data

Fig. 1 Orobanche ritro. France, Rabou près Gap, sur l’Echinops ritro, 14 VIII 1848, Grenier (P). Lectotype.

Fig. 2 Calyx segments. Orobanche ritro: a) France, Rabou (P) (lectotype), b) Spain, Huesca, Ortilla, (JACA 344296); c) Romania, Ad vallum Romanorum legionum Serbio-banaticae, (WU 771). O. elatior: d) England, Hants, Bury Hill, Andover (K); e) Hungary, National Park of Hortobágy (COA 16491); O. icterica: f) Spain, Alicante, Cap de les Hortes (COA 25532); g) Spain, Almería, Vélez Blanco (COA 37658).

Table I. Main differences between O. ritro Gren. & Godr., O. elatior Sutton and O. icterica Pau.

Character	O. ritro	O. elatior	O. icterica
Stem base diameter (mm) /thickness	8–10 Slightly swollen	(7)11–30 Slightly swollen to bulb-shaped	9–14 Slightly swollen to clavate
Basal leaves	Sub-imbricate to sparse	Densely imbricate	Densely imbricate
Upper leaves, width (mm)	3.5–6(9)	(2)3–5(6)	4.5–8.5
Upper leaves, shape	Widely lanceolate to ovate	Lanceolate, narrow	Ovate to narrowly ovate
Calyx height (mm)	10–16(19)	9–15	(7)8–11(15)
Calyx segments, position	Free, separated or contiguous, rarely connate	Highly connate at base	Contiguous, occasionally connate at base
Calyx segments, form, apex	Shortly bipartite to bifid, occasionally emarginate	Deeply bipartite	Bipartite
Calyx, tooth/total height ratio	1/2–1/3(1/5)	1/2 –2/3(3/4)	⩽ 1/2
Calyx, base hair-covering	Scarcely hairy to glabrescent, glandular hairs ⩽ 0.2 mm	+/– hairy, glandular hairs ⩽ 0.5 mm	+/– hairy, glandular hairs ⩽ 0.3 mm
Calyx, tooth hair-covering	Glandular hairs ⩽ 0.6 mm	Glandular hairs ⩽ 0.5 mm	Glandular hairs ⩽ 0.4 mm
Corolla, shape	Tubular	Tubular to slightly infundibuliform, slightly narrowed below insertion of filaments	Slightly infundibuliform, narrowed below insertion of filaments
Corolla, dorsal line	Straight to slightly curved	Uniformly curved	Uniformly curved
Corolla, base hair-covering	Glabrescent, short glandular hairs < 0.2 mm	Hairy, short glandular hairs ⩽ 0.2 mm, +/– abundant	Glabrescent, very short glandular hairs < 0.05 mm
Corolla, limb hair-covering	Glandular hairs ⩽ 0.3 mm	Glandular hairs ⩽ 0.5 mm	Glandular hairs ⩽ 0.2 mm
Corolla, colour	Yellowish to creamy	Yellowish or yellowish–brown with a red tinge	Yellowish or yellowish–brown with a red tinge
Adaxial filament insertion above corolla base (mm)	(3)4.5–6	(3)4–5(6)	(2)3–4(5.5)
Abaxial filaments, margin base	Straight	Straight	Auriculate
Filaments, hair covering in lower half	Densely pubescent	Densely pubescent	Scarcely or minutely pubescent
Filaments, hair length in lower half (mm)	0.3–0.7	0.5–1.2	0.1–0.5
Anthers, length (mm)	1.5–1.9	(1.8)2–2.2(2.5)	(1.8)1.9–2.1(2.5)
Host	Echinops ritro L. E. sphaerocephalus L.	Centaurea scabiosa L. C. nigra L.	Centaurea aspera s.l. C. ornata Willd. Rhaponticoides alpina (L.) M. V. Agab. & Greuter