Limonium cophanense C. Brullo, Brullo, Cambria, Giusso & Ilardi, 2016

Brullo, Cristian, Brullo, Salvatore, Cambria, Salvatore, Galdo, Gianpietro Giusso Del & Ilardi, Vincenzo, 2016, Limonium cophanense (Plumbaginaceae), a new species from Sicily, Phytotaxa 255 (2), pp. 153-159 : 153-158

Limonium cophanense C. Brullo, Brullo, Cambria, Giusso & Ilardi , sp. nov. ( Figs. 1 , 2A–C )

Type: ― ITALY. Sicily: Versante orientale di Monte Cofano, presso Trapani, costa rocciosa calcarenitica, 38° 06’ 19’’ N, 12° 41’ 42’’ E, 02 July 2012, Brullo & Ilardi s.n. (holotype CAT!).

Diagnosis: ― Recedit ab Limonium bocconei habito prostrato-adscendente, foliis spathulatis, 8‒30 cm longis, retusis, ramis inflorescentiae arcuatis vel arcuato-reflexis, spiculis leviter curvatis, bractea inferiore 1.2‒1.5 mm longa, apiculo attingens marginem superiorem, bractea media 1.5‒1.9 × 1.0‒ 1.2 mm, bractea superiore obtuse, apiculo centrali attingens marginem superiorem, calyce 3.7‒4.2 mm longo, glabro, ex bractea superiore 1.8‒2.0 mm exserto, lobis triangularibus, 0.7‒0.8 mm longis.

Description: ―Plant perennial (small shrub), glabrous, 15 ‒ 30 cm tall, with several prostrate-ascending stems, protruding from a robust and compact tap-root. Caudices 5 ‒ 10 cm long, branched, with leaves in apical poor rosettes. Leaves rigid, green, slightly rugose, dry at flowering, spathulate, 8 ‒ 30 × 2 ‒ 9 mm, retuse at apex, slightly revolute at margin, 1-nerved, gradually tapering into the petiole. Stems green, laxely rugose-punctate, rigid, fragile at nodes, slightly, often branched from the base, with internodes 8–20 mm long and several sterile branches. Inflorescence terminal, branched, with branches arcuate to arcuate-reflexed. Spikes 10 ‒ 35 mm long. Spikelets 1 ‒ 2-flowered, 5 ‒ 6 per 1 cm. Outer bract 1.2 ‒ 1.5 × 1.0 ‒ 1.4 mm, triangular-ovate, acuminate, with margin broadly membranous and apiculum reaching the apex. Middle bract membranous, 1.5 ‒ 1.9 × 1.0 ‒ 1.2 mm, oblong, rounded at the apex. Inner bract 3.3 ‒ 3.8 × 2.0 ‒ 2.5 mm, oblong, obtuse, with margin broadly membranous, central part fleshy, lanceolate, acuminate, forming a narrowly triangular tip, 0.5 ‒ 0.8 mm long, reaching the upper margin. Calyx 3.7 ‒ 4.2 mm long, exceeding the inner bract by 1.8 ‒ 2.0 mm, glabrous, with 5 ribs ending in the middle of the lobes; calyx lobes triangular, 0.7 ‒ 0.8 mm. Corolla pale violet; petal spathulate, retuse at apex. Seeds fusiform, 1.8 ‒ 2 mm long.

Etymology:— The specific epithet refers to Cofano, a mountain of North-West Sicily.

Phenology: ―Flowering from July to September, fruiting up to October.

Habitat and distribution: ― Limonium cophanense is a halophyte circumscribed to a narrrow area of the rocky coast eastward of Mt. Cofano, an isolated coastal mountain between Trapani and San Vito lo Capo (North-West Sicily, Fig. 2 ). It grows on calcarenitic outcrops of Plio-Pleistocene origin ( Abate et al. 1998), while in the neighboring Mesozoic limestones it is replaced by the allied Limonium bocconei ( Fig. 3 ). The site is directly affected by the marine aerosol, and L. cophanense is a member of a halophilous vegetation characterized by, e.g., Crithmum maritimum Linnaeus (1753: 246) , Asteriscus maritimus Lessing (1832: 210) , Lotus cytisoides Linnaeus (1753: 776) , Plantago macrorrhiza Poiret (1789: 114) , Frankenia hirsuta Linnaeus (1753: 331) and Silene sedoides Poiret (1789: 164) .

Conservation status: ―According to the IUCN Red list category and criteria ( IUCN 2014), Limonium cophanense can be classified as “Endangered” (EN C1), because of the low number of individuals (less than 500) and the reduced distribution area (less than 1 km 2).

Taxonmic remarks: ― Limonium cophanense shows morphological similarities with L. bocconei , endemic species growing on the Mesozoic limestones between Trapani and Termine Imerese, as well as in the islets of Favignana and Levanzo (Egadi Archipelago). These species share several morphological characters, such as the caudices which are well developed with few leaves at the apex of branches, dry at anthesis, stems numerous, with many sterile branches, fragile at nodes and spikes with spaced small spikelets. However, L. bocconei differs from L. cophanense in having stem erect, up to 50 cm tall, densely rugose-punctate, the leaves up to 45 mm long, often rounded at the apex, spikes curved, the spikelets straight with outer bract 1.6 ‒ 2.0 mm long with apiculum no reaching the apex, middle bract 1.9 ‒ 2.2 mm long, inner bract rounded with apiculum no reaching the upper margin, calyx 4.2 ‒ 4.6(‒ 5.0) mm long, hairy at the base, with ribs no reaching the base of the lobes.

Another related species is L. usticanum Giardina & Raimondo in Peruzzi et al. (2015: 126) which was recently described from Ustica (a volcanic islet near Palermo). L. usticanum differs from L. cophanense for laxer spikes, spikelets 2 ‒ 3(‒ 4)-flowered, longer calyx (4.5 ‒ 4.7 mm long), exserted 2.0 ‒ 2.5 mm from inner bract.

Moreover, L. cophanense has the same ecological requirements of L. flagellare ( Lojacono 1907: 27) Brullo (1980: 284) , a species circumscribed to several localities of the gulf of Castellammare del Golfo (westward of Palermo), where it mainly occurs on arenaceous and calcarenitic rocks. L. flagellare belongs to the L. bocconei group, and clearly differs from L. cophanense for several features concerning the habit, shape and size of leaves, spikes, spikelets, bracts and calyx (see Table 1).

Eventually L. ponzoi ( Fiori & Béguinot 1927: 384) Brullo (1980: 284) , a species occurring in some areas located to the east of Trapani, as well as on the islets of Favignana and Levanzo. It differs from L. cophanense especially for the larger leaves, green at the anthesis, more lax spikes and also for the larger bracts and calyx (see Table 1).

Additional examined species (paratypes): ITALY. Sicily: Costa rocciosa calcarenitica a Est di Monte Cofano, presso Trapani , 03 July 2015, Cambria s.n. ( CAT!) ; Sicily: Costa rocciosa calcarenitica a Est di Monte Cofano, presso Trapani , 16 September 2015, Cambria s.n. ( CAT!) ; Sicily: Costa rocciosa calcarenitica a Est di Monte Cofano, presso Trapani , 12 November 2015, Cambria & Ilardi s.n. ( CAT!) .

Figures

FIGURE 1. Diagnostic features of Limomium cophanense. A. Habit. B. Inflorescence. C. Spikelet. D. Calyx. E. Calyx teeth. F. Outer bracts. G. Inner bracts Middle bracts. H. Inner bracts. I. Leaves. Drawing by S. Brullo based on living material coming from the type locality (CAT).

FIGURE 2. Maps of Limomium cophanense (red dot), L. bocconei (green dots), L. flagellare (blue dots) and L. ponzoi (yellow dots) in NW Sicily.

FIGURE 3.A. Habit of Limonium cophanense.B. Calcarenitic rocky coast colonized by L.cophanense. C. Inflorescence of L.cophanense. D. Habitat and habit of L. bocconei. (A−C: photos by V. Ilardi, D: photo by S. Brullo).