Achyranthes sicula (L.) All., Auct. Syn. Meth. Stirp. Hort. Regii Taur.: 41 (1773)

Sukhorukov, Alexander P., Kushunina, Maria, Nilova, Maya V., Baider, Cláudia & Sennikov, Alexander N., 2024, Africa and Arabia encompass a much greater species diversity in the Achyranthes aspera aggregate (Amaranthaceae, achyranthoid clade): Evidence from morphological and chorological data, PhytoKeys 250, pp. 21-94 : 21-94

Achyranthes sicula (L.) All., Auct. Syn. Meth. Stirp. Hort. Regii Taur.: 41 (1773) .

≡ Achyranthes aspera var. sicula L. , Sp. Pl. 1: 204 (1753) .

≡ Achyranthes argentea Lam., Encycl. 1 (2): 545 (1785), nom. illeg. superfl.

≡ Cadelaria sicula (L.) Raf. , Fl. Tellur. 3: 39 (1837).

≡ Cadelaria argentea Raf. , Autik. Bot.: 154 (1840), nom. illeg. superfl.

≡ Achyranthes aspera var. argentea Eggers , Vidensk. Meddel. Naturhist. Foren. Kjøbenhavn 1876: 140 (1877), nom. illeg. superfl.; Boiss., Fl. Orient. 4: 994 (1879), isonym; C. B. Clarke in Th. - Dyer, Fl. Trop. Afr. 6 (1): 63 (1909), isonym.

– Achyranthes aspera [var. sicula] f. albida Maire & Weiller , Fl. Afr. Nord. 8: 219 (1962), nom. inval. descr. gall.

Lectotype (designated by Townsend 1994).

“ Amaranthus radice perpetua ” in Herb. Boccone (P).

Description.

(Fig. 17 ). Annual (probably also short-lived perennial), 30–200 cm tall; stem stout, four-angled; leaves shortly petiolate (petioles 5.0–15.0 mm long), blades 25–100 × 15–40 mm, ovate, base broadly cuneate or truncate, tip attenuate, bicolored, green above and white silvery below; inflorescence up to 30 cm long; bract 3.0–4.0 mm long; bracteoles 3.0–4.0 mm long, slightly reflexed, green or usually pink; perianth (3.5) 4.0–5.0 mm long, segments ± equal, white, pinkish or green and then turning gray; stamens 5 with white or mauve filaments, anthers 0.5–0.8 mm long; pseudostaminodes 0.5–1.2 mm long, fimbriate, white or pink, style with stigma (1.2) 1.5–1.8 mm long; fruit (without style) 1.7–2.0 mm long.

Taxonomic note.

Only a limited number of specimens were collected with subterranean parts, and the species seems to be annual despite literature references where it is considered as a perennial or suffruticose herb (e. g., Maire 1962, as A. aspera ; Zohary 1966, as var. sicula ).

Nomenclatural notes.

Linnaeus (1753) validly published Achyranthes aspera var. sicula without a description or diagnosis but with a citation of “ Amaranthus siculus spicatus. Bocc. sic. 16. t. 9. Pluk. phyt. 260. f. 2 ”. This pre-Linnaean polynomial is not diagnostic because its only descriptive word, “ spicatus ”, is part of the polynomials similarly cited under another variety of this species, var. indica . For this reason, a validating description of the Linnaean variety is one of the descriptions provided by Boccone (1674) and Plukenet (1691), which were referred to in the protologue. Both descriptions are also accompanied by illustrations, directly cited by Linnaeus (1753), which are part of the original material of the variety. Another part is the specimens associated with the descriptions, namely the herbarium collection of L. Plukenet at BM (Herb. Sloane!) and that of P. Boccone at P. Townsend (1994: 21) accepted Boccone (1674) as a source for the validating description and designated the corresponding specimen “ Amaranthus radice perpetua ” in Herb. Boccone at P. Although Townsend (1994) made it clear that he designated a herbarium specimen at P, Iamonico (2014) doubted his citation and designated another specimen in Herb. Linnaeus (287.1) at LINN as a new lectotype. The latter specimen is not linked to the validating description of the variety (which is not Linnaean), and therefore Iamonico’s choice is not effective. The lectotype designated by Townsend is technically correct and should be accepted.

When publishing his A. argentea, Lamarck (1785) included a full and direct reference to the pre-Linnaean polynomial in its protologue, which was the sole basis of A. aspera var. sicula . Under Art. 52.3, Lamarck’s species name is an illegitimate replacement of A. sicula (L.) All. The lectotype of A. argentea designated by Raus (2022), a specimen from cultivation in the Botanical Garden in Paris and kept at SEV, therefore has no standing.

Habitat.

Calcareous soils, rocks, disturbed areas at elevations of 0–1500 m a. s. l.

Distribution.

(Fig. 18 ; see also Appendix 1). Africa: Algeria, Cape Verde, Egypt, Morocco, Spain (Canary Islands), Tunisia, and probably Libya (no specimens seen).

General distribution.

Mediterranean basin: Algeria, Egypt, Malta, Morocco, Tunisia, British Overseas Territory [ Gibraltar], Greece (very rare: Raus 2022), Israel / Palestine, Lebanon, Portugal (Azores and Madeira), Syria, southern part of Italy, Spain. The records of A. aspera from Jordan ( Taifour and El-Oqlah 2017) probably belong to A. sicula .

Notes on other species growing in the regions under study

Two other Achyranthes s. str. in Africa have been accepted because of their unique characters: A. fasciculata (e. g., Townsend 1985) and A. talbotii ( Cavaco 1962; Townsend and Darbyshire 2004). The first species is a mountainous scandent shrub with fasciculate inflorescences. Achyranthes talbotii is a perennial rheophytic herb frequently rooting at lower nodes, with lanceolate or narrowly oblong leaves. Below we provide currently known localities and distribution maps for both species.

Figures

Figure 17. Achyranthes sicula A plant in vegetative stage (Santa Cruz de Tenerife, Canary Islands) B close-up of the inflorescence (Santa Cruz de Tenerife, Canary Islands). Photographer: F. Bednár.

Figure 18. Distribution map of Achyranthes sicula.