Calendula suffruticosa subsp. marsaensis A.C. Gonç. & P. Silveira, 2023

Gonçalves, Ana Carla, Ouhammoud, Ahmed, Amirouche, Rachid, Santos, Conceição, Figueiredo, Estrela & Silveira, Paulo, 2023, A taxonomic revision of Calendula (Asteraceae) in Morocco, including some taxa from Algeria and Tunisia, Phytotaxa 605 (1), pp. 1-83 : 51

11i. Calendula suffruticosa subsp. marsaensis A.C. Gonç. & P. Silveira , subsp . nov. Type :— MOROCCO. Tanger, Oued Marsa, 3–5 m, [35°54’ N, 5°27’ W], 13 June 2012, P. Silveira & A. C. R. S . Gonçalves 3268 (holotype RAB!; isotypes AVE!, MARK!) .

Diagnosis:— Calendula suffruticosa subsp. marsaensis differs from C. suffruticosa subsp. suffruticosa by the presence of trialate achenes.

It differs from subsp. guruguensis by having triallate achenes with (11.7) 12.4–13.8 (14.5) mm, with length/width> 1.5, instead of

(6.3) 8.5–9.8 (10.3) mm, with length/width approx. 1.

Description:––Perennial herbs. Stems (24) 30.3–36.3 (43) cm long, erect to ascending, with glandular hairs distally and predominance of non-glandular white-arachnoid pubescence proximally, not viscid/viscous. Basal leaves (3.5) 4– 5.5 (6) × (0.9) 1.1–1.7 (1.8) cm, 0.4–0.6 (0.7) mm thick, obovate to oblong, apex obtuse, margins sub-entire to slightly sinuate-dentate, densely white-arachnoid pubescent, with progressively less white-arachnoid and more glandular pubescence towards the apice of the stems. Capitula solitary, 1.7–2.6 (3) cm diameter. Outer achenes rostrate (12) 17.8–24 × (1.3) 1.6–2.2 (2.3) mm, ± straight or slightly curved, without dorsal spines, without a ventral basal tooth; middle achenes bialate (10.3) 10.8–17 (18) × (5) 5.8–8.3 (8.8) mm, with a rostrum (2.5) 2.6–6.9 (7.5) mm, to trialate (11.7) 12.4–13.8 (14.5) × (8.8) 9.1–9.2 mm, lateral wings sinuate-dentate to incised; inner achenes vermiculate-exalate (3,7) 4,8–5,3 (5,5) × (1,2) 1,8–2,2 (2,3) mm, hemicyclic to circular. Figure 17 .

Habitat and distribution:—We found this taxon growing slightly above sea level only. However, in herbarium there are specimens (Davis 51121B) collected at elevations of 400–500 m in 1971. It is found in sub-humid Mediterranean bio-climate. Endemic to Morocco with a distribution that seems to be restricted to the NW foot of Jbel Mousa, margins of Oued Marsa (Tetouan).

Conservation status:—Critically Endangered (CR). This taxon is under numerous threats, especially due to climate change (extreme weather, rise in sea level), and human intervention. The subspecies is rare and local with a small-restricted range; only one population is known and suffering from high habitat degradation due to human pressure. The number of mature individuals is estimated to be <50 based on field observations. The AOO is 4 km 2. It is unlikely that more populations exist, therefore we propose a conservation status of CR B2ab (iii, v), C2a (i, ii), D.

Chromosome number:— 2n = 32.

Genome size:—3.44 ± 0.12 pg.

Eponymy:—For Oued Marsa in Morocco where it occurs.

Additional collections:— MOROCCO. Tanger-Tetouan-Al Hoceïma : Tanger Jbel Mousa, 400–500 m, [35°53’53” N, 5°24’35” W], 9 April 1971, P. H . Davis 51121 B ( BM!); Tanger, Jbel Musa, [35°53’53” N, 5°24’35” W], 25 May 1930, P . Font Quer s.n. ( BC!); Tanger Jbel Moussa (Mont aux Singes), [35°53’53” N, 5°24’35” W], June 1977, Benabib s.n. ( RAB!) .

Figures

FIGURE 17. Variability of achene morphology of Calendula. A. C. suffruticosa subsp. trialata (Silveira & Gonçalves 3267, AVE); B. C. suffruticosa subsp. marsaensis (Silveira & Gonçalves 3268, AVE); C. C. suffruticosa subsp. lusitanica (Silveira & Gonçalves 3269,AVE); D. C. suffruticosa subsp. dersana (Silveira & Gonçalves 3262, AVE); E. C. suffruticosa subsp. hosmarensis (Silveira & Gonçalves 3261, AVE); F. C. suffruticosa subsp. riffensis (Silveira 3341, AVE); G. C. suffruticosa subsp. tazaensis (Silveira & Gonçalves 3334, AVE); H. C. suffruticosa subsp. boccoyana (Silveira & Gonçalves 3266, AVE); I. C. suffruticosa subsp. boccoyana (Silveira & Gonçalves 3340, AVE); J. C. suffruticosa subsp. guruguensis (Silveira & Gonçalves 3265, AVE); K. C. suffruticosa subsp. fulgida (Silveira & Gonçalves 3335, AVE). Rostrate achenes: A1, 2; B1, 2; C1, 2; D1, 2; E1, 2; F1-3; G1, 2; H1, 2; I1, 2; J1, 2; K1-4. Bialate achenes: A3; B3, 4; C3, 4; D3; E3; F4, 5; G3-5. Cymbiform achenes: D4-6; E4, 5; F6, 7; G6, 7; H3, 4; I3, 4; K5, 6. Sub˗cymbiform achenes: B4, E4, E5, J3, J4. Trialate achenes: A4, 5; B5; J3, 4. Exalate achenes: C5, 6. Vermicular-alate achenes: F8; G8; I5; K7. Vermicular-exalate achenes:A6, B6, 7; C7; D7, 8; E6; F9; G9, 10; H5; I6; J5; K8.All achenes in side view, except: A3-5, B3-5, C3-6, D3, D5, E3, E4, F4-7, G3-6, H3, I3, J3, K2, and K5 in ventral face view, and D6, G7, H4, I4, J4, K1, and K6 in ± dorsal face view. Scale bars = 1 cm.