Malvella sherardiana, or Sherard's malvella, is a perennial flowering plant in the mallow family (Malvaceae), native to Spain and from Greece to Crimea, southeastward to Iran. The species features many ground-spreading stems with round, long-stalked leaves up to wide with crinkly edges, and small, solitary pink mallow-like flowers measuring in diameter. It is the only Old World species in the genus Malvella, typically growing in fields and waste places on heavy clay soils at elevations between 0âÂÂ, where it faces conservation challenges, particularly in central Spain where it qualifies as endangered with fewer than 300 individuals remaining across fragmented populations.
The plant is a perennial found in fields and waste places (0âÂÂ1000 m) consisting of many ground-spreading stems, with many round long-stalked leaves (to 50 mm wide) with crinkly edges and sizeable gap at base, and small long-stalked mallow-like solitary pink flowers (10 mm diam), each with five unnotched and many . The fruit is a ring of many inflated segments. All parts are densely short-hairy with star-like () hairs.
The main veins of the leaves radiate from the leaf base to the edge, with secondary . The epicalyx at the base of the is inconspicuous, composed of three small (1âÂÂ2 mm) filamentous parts.
The seeds of Malvella sherardiana show a form of physiologicaldormancy caused by the mechanical resistance of their tough seed coat, rather than by impermeability to water or underdevelopment of the embryo. Under controlled laboratory conditions (constant temperatures of and alternating regimes of 15/25âÂÂ25/35 ðC), fewer than 5% of untreated seeds germinated after 13 weeks, rising only to about 5% following a 24 h soak in gibberellic acid. WaterâÂÂimbibition trials showed that intact and scarified seeds absorb similar amounts of moisture (about 17âÂÂ20 % increase in mass after 24âÂÂ48 h), confirming that the dormancy is not due to a waterâÂÂimpermeable coat.
By contrast, brief chemical scarification with concentrated sulfuric acid (H<sub>2</sub>SO<sub>4</sub>) markedly improved both germination percentage and speed: seeds treated for three hours in H<sub>2</sub>SO<sub>4</sub> and then soaked in gibberellic acid reached up to 77% germination and reduced mean germination time to around four days. Mechanical tests found that an average force of about 58.8 N is required to fracture the seed coat, underscoring its role as a physical barrier to radicle (first root) emergence. These results suggest that simple acidâÂÂscarification protocols could be adopted in ex situ conservation and ecological restoration programmes to enhance propagation success for this vulnerable species.
Malvella sherardiana occurs in Bulgaria, Cyprus, East Aegean Islands, Greece, Iran, Iraq, Crimea, Lebanon-Syria, North Caucasus, Palestine, Spain, Transcaucasus, and Turkey.
In Spain, all known wild populations of M. sherardiana occupy heavy, expansive clay soils (vertisols), typically in ruderalâÂÂarvense or pastizalâÂÂcardal communities subject to grazing and trampling. In the newly reported Toledo locality (Numancia de la Sagra, 560 m) plants grow on brown clays with a sparse herbaceous cover. Similar substrates and vegetation occur at all confirmed sites in ÃÂvila, Madrid and Toledo.
Following IUCN criteria applied at the scale of central Spain (only five 10 km by 10 km UTM squares occupied and a sharp recent decline), the species would qualify as Endangered (EN) in CastillaâÂÂLa Mancha. 2016 population estimates are roughly 250 individuals across all Madrid fragments and about 45 in Toledo. Legal protection is currently limited to Castile and León (); in Madrid and CastillaâÂÂLa Mancha the species remains unprotected and faces imminent loss of urbanâ and infrastructureâÂÂbound sites.