Trifolium pratense var. semipurpureum, Strobl, 1887

Iamonico, Duilio, Domina, Gianniantonio, Guarino, Riccardo & Guacchio, Emanuele Del, 2021, Nomenclatural notes on Fabaceae described from Sicily, Phytotaxa 490 (2), pp. 211-219 : 212

Trifolium pratense var. semipurpureum

Trifolium pratense var. semipurpureum Strobl (1887: 104) was validly described with a short diagnosis in German. The following citation was reported in the protologue: “ Trifolium pratense ... var. semipurpureum m. [mihi] = var. flavicans Guss. Syn. et Herb. !, Tod. Fl. sic. exsicc. Nr. 393!, non DC. Prodr. II, 195”. Strobl (1887) so referred to Trifolium pratense var. flavicans Candolle (1825: 195) , misapplied by Gussone (1843 –1844: 330) to a Sicilian taxon. Strobl (1887) cited also a pertinent specimen by Gussone, whose collections are mainly housed at NAP (Collections “Gussone - Generale” and “Gussone - Sicilia ”). In addition, “Tod. Fl. sic. exsicc. Nr. 393!” refers to a syntype (Art. 9.6 of ICN) included in the Todaro’s collection, mainly preserved at PAL (see Stafleu & Cowan 1986: 378). Strobl (1887: 105) reported in the protologue also the following Sicilian localities: “Nicolosi and San Nicolá, im Valle Calanna und Val del Bove, im Bosco Maletto oberhalb Bronte”.

We traced at NAP and PAL the syntypes cited by Strobl (1887: 104). At NAP, only a pertinent sheet was found (R. Vallariello, pers. com.). It was labelled by Gussone as “13.b Trifolium pratense var. floribus albis ”, therefore not perfectly matching the name adopted in Gussone (1843 –1844: 330); however, the code reported on the label, i.e. “13.b” just corresponds to the collocation of the variety in the Synopsis ( Gussone 1843 –1844). Another label, again handwritten by Gussone, indicates the gathering locality: “Ficuzza” (Corleone municipality, northern Sicily). This is the only locality reported by Gussone (1843 –1844: 331) for T. pratense var. flavicans , except for another one provided by T. de Heldreich. The specimen is represented by a single individual with four flowering stems. This individual is not readily referable to T. pratense subsp. semipurpureum , as it shows intermediate features towards T. pratense subsp. pratense , especially regarding the position of the marginal flowers, the shape of leaves, and the weak hairiness. For this latter feature, it apparently does not agree with the protologue ( Strobl 1887) (but see Art. 9.19, Note 7 of ICN).

The specimen by Todaro bears three plants (parts of a single gathering; see Art. 9.17 of ICN) and the following label: “Todaro Flora Sicula Exsiccata | Trifolium pratense Linn. sp. Pl. p. 1082. var. flavicans Dec. prodr. 2, p. 195 | In pratis montosis― Madonie. | Junio | N. 393. Legit. Todaro ”. This specimen, which corresponds to the Strobl’s diagnosis, is designated here as the lectotype of the name Trifolium pratense var. semipurpureum , as it better matches with the current circumscription of this taxon.

We support the recognition by Pignatti (2018: 620) at subspecies rank for this taxon, which appears as a well segregated ecotype widespread throughout the Apennines and in Sicily, adapted to the mountain meadows and especially characterized by reduced habit, usually dense and adpressed hairiness, single terminal heads no more than 2 cm wide, with marginal flowers upwards directed and rounded leafleats, stipel tips 1/4–1/6 as long as the expanded part ( Pignatti 1982).

Trifolium pratense subsp. semipurpureum (Strobl) Pignatti (1973: 218) ≡ T. pratense var. semipurpureum Strobl (1887: 104)

Type (lectotype, designated here):— SICILY: Palermo, Madonie, in pratis montosis, June [XIX century], Todaro 393 (PAL2016!).

− Trifolium pratense var. flavicans sensu Gussone (1843 –1844: 330), non Candolle (1825: 195).