Trifolium spumosum L. Sp. Pl. 2: 771. 1753 [1 May 1753]

Scoppola, Anna, Lattanzi, Edda & Bernardo, Liliana, 2016, Distribution and taxonomy of the Italian clovers belonging to Trifolium sect. Vesicastrum subsect. Mystillus (Fabaceae), Italian Botanist 2, pp. 7-27 : 14-15

Trifolium spumosum L. Sp. Pl. 2: 771. 1753 [1 May 1753]

Type

(lectotype designated by Zohary and Heller 1984: 274): In Gallia, Italia, Apulia. Hort. Clifford, 373, 7 (BM).

Description.

Flowering heads small (15-20 mm); fruiting calyx vesicular-turbinate, netted-nerved; corolla short, slightly protruding from the calyx ( Figure 2A '), seed ovoid, light brown.

Updated geographical distribution.

Liguria: 0 (new), Tuscany: 0 (new), Marche: 0, Lazio: +, Abruzzo: 0 (new), Campania: 0 (new), Apulia: 0 (new), Basilicata: 0 (new), Calabria: +, Sicily: +, Sardinia: +.

Notes.

It is a widespread steno-Mediterranean thermophilous and xerophilous species, especially found in dry uncultivated lands of coastal areas. It was described on the basis of collections made in Italy and France. Based on our data, the distribution in Italy is very fragmented and in decline, especially in the central regions. A similar depletion has been reported in southern France where the species is classified as naturalized over most of the territory ( Coulot and Rabaute 2013). It is quite widespread in Sicily ( Giardina et al. 2007, La Rosa 2011), where it mostly grows in arid uncultivated hilly and mountain areas. However, its current presence in the Italian southern regions, especially in Campania and Apulia, has probably been underestimated due to confusion with other taxa (e.g. Trifolium vesiculosum , Trifolium resupinatum L.).

Peccenini (2007) cites the report by Bertoloni (1850) "ex Liguria orientali in litore Clavarensi a Turio; Genua all’Acquasola a Vincentio" and by Fiori (1925) for Liguria; moreover her recent report in the outskirts of Sarzana (FI!, GE; Peccenini 2007) must be corrected, as the sample actually refers to Trifolium resupinatum . Thus, we record the species as requiring confirmation in Liguria. Concerning Tuscany, no herbarium material can confirm the historical records of this species between Grosseto and Castiglione della Pescaia (Savi in Caruel 1862, Pignatti 1982, Selvi 2010), but several specimens from the Elba, Giglio, and Pianosa islands (FI!) confirm its presence in the past. Also in need of confirmation is its occurrence in Marche, where it was collected in Senigallia (Ancona) in 1876 (FI! as Trifolium vesiculosum ; Gubellini et al. 2014). The occurrence of the species in Abruzzo ( Conti 1998) is by Zodda (1954) and by Crugnola (1894, 1900) who refers to a sample by Petrilli from the Mavone valley (Valle del Vomano, Teramo); we have been unable to trace it. The occurrence in Campania and Basilicata ( Conti et al. 2005) is only based on historical records from the outskirts of Avellino, "Ad Aiello del Sabato" ( Milani 1890, Casali 1901, Trotter 1905) and Caserta at S. Silvestro ( Terracciano 1872) and on a gathering from an unknown locality by Tenore (NAP; A. Santangelo, pers. com.).

The Apulian material dating back to the 1970s, deposited in PAD and labeled as Trifolium spumosum , actually refers to Trifolium resupinatum . Trifolium spumosum has been reported from Apulia by Conti et al. (2005) based on these gatherings and on Bertoloni (1850), who cited a specimen collected in Foggia by Gussone (NAP!). The species is also reported in Salento by Bruni (1857) and Marinosci (1870), confirmed by Mele et al. (2006) and - for the Province of Brindisi - by Tomaselli et al. (2010). As no recent samples were found either in LEC or BI (P. Medagli and V. Tomaselli, pers. com.), we still consider the species in need of confirmation for the current Apulian flora. The presence in Lazio, Calabria, and Sardinia ( Conti et al. 2005) is confirmed.

Figures

Figure 2. Comparison between mature calyces of Trifolium subsect. Mystillus species in Italy (bar = 1 mm). Left: Trifolium vesiculosum (A) and Trifolium spumosum (A '), middle Trifolium multistriatum transitional (B) and typical (B ') forms, right Trifolium mutabile s. str. (C) and Trifolium mutabile var. gussoneanum (C ').