Convolvulus siculus subsp. elongatus Batt., Fl Algerie : 595. 1890. (Battandier 1890: 595).

Wood, John R. I., Williams, Bethany R. M., Mitchell, Thomas C., Carine, Mark A., Harris, David J. & Scotland, Robert W., 2015, A foundation monograph of Convolvulus L. (Convolvulaceae), PhytoKeys 51, pp. 1-282 : 118

87b. Convolvulus siculus subsp. elongatus Batt., Fl Algerie: 595. 1890. (Battandier 1890: 595).

Convolvulus pseudosiculus Cav., Descr. Pl. 97. 1801. ( Cavanilles 1801: 97). Type. Cultivated plant (holotype MA 222471!).

Convolvulus elongatus Willd., Enum. Pl. 205. 1809, illegitimate superfluous name for Convolvulus pseudosiculus Cav. ( Willdenow 1809: 205). Type. Cultivated plant of uncertain origin (lectotype B-W03724010, designated here).

Evolvulus agrestis Schweinf., Beitr. Fl. Aethiop. 92. 1867. ( Schweinfurth 1867: 92). Type. ETHIOPIA, Schimper 73 (holotype B†; isotype P).

Convolvulus refractus Pomel, Nouv. Mat. Fl. Atl. 1: 84. 1874. (1874: 84). Type. ALGERIA, Mers-el-Kebir, Pomel s.n. (holotype AL, not seen).

Convolvulus agrestis (Schweinf.) Hallier f., Bot. Jahrb. Syst. 18: 101. 1893 [ “1894”], comb. illeg., non Convolvulus agrestis Mart. ex Choisy (1845). ( Hallier 1893: 101). Type. Based on Evolvulus agrestis Schweinf.

Convolvulus siculus subsp. agrestis (Schweinf.) Verdc., Kew Bull. 12: 344. 1957. ( Verdcourt 1957: 344). Type. Based on Evolvulus agrestis Schweinf.

Type.

Based on Convolvulus elongatus Willd.

Distinguishing features.

Bracteoles filiform, pedicels 5-10 mm long so bracteoles distant from sepals. [ Verdcourt 1963: 41].

Distribution.

Principally in NW Africa and the southern Red Sea area: Canary Islands (Bourgeau 458, Aedo et al. 12447); Spain (Bourgeau 1295); Portugal (?); Sardinia (fide Stace 1972); Morocco (Trethewy 109, Jury et al. 14203, Jahandiez 222); Algeria (Romieux s.n. [29/4/1883]); Sudan (Schweinfurth 2192); Ethiopia (Schimper 362, 1294); Eritrea (Ryding 1411, Pappi 1757); Somalia (Thulin & Gifri 8711); Socotra (Popov SO/331); Yemen (Wood Y/72/177); Saudi Arabia (Collenette 488). Rare and scattered elsewhere: Tanzania (Peter 43022); Kenya (Kokwaro 2840); Oman: Dhofar (Miller & Nyberg 9133, Mandaville 7359); India (Beddome 5618 (BM), from Secunderabad).

Notes.

As a species Convolvulus siculus is distinctive because of its petiolate, basally truncate leaves and blue flowers.

Some publications (e.g. Dobignard and Chatelain 2011) treat subsp. elongatus and subsp. agrestis as separate taxa but there seems to be no reason for this.

Convolvulus elongatus is illegitimate as Willdenow cited the earlier Convolvulus pseudosiculus in synonymy. The change of type face in Battandier (1890: 595) indicates Convolvulus elongatus is being treated as a subspecific name of Convolvulus siculus following an earlier explanation ( Battandier 1890: 4).