Ephedra aurea Brullo, C. Brullo, Cambria, Ilardi, Siracusa & Giusso, 2022

Brullo, Salvatore, Brullo, Cristian, Cambria, Salvatore, Ilardi, Vincenzo, Siracusa, Giuseppe & Galdo, Gianpietro Giusso Del, 2022, Ephedra aurea (Ephedraceae), a new species from Sicily, Phytotaxa 530 (1), pp. 1-20 : 9-14

Ephedra aurea Brullo, C. Brullo, Cambria, Ilardi, Siracusa & Giusso sp. nov. (Figs. 2,3,4)

Type: ITALY. Sicily: Trapani, Penisola di San Vito lo Capo , versante costiero occidentale in località “Isulidda” a Nord di Macari , 50 m di altitudine, 38°08’44” N, 12°44’09” E, 30 June 2012, S. Brullo & V. Ilardi s.n. (holotype, CAT; isotypes, CAT) .

Ephedra nebrodensi affinis, sed ramulis divaricatis, ad nodos laxe insertis, luteolo-viridibus 1–2.5 mm diametro, internodiis usque ad 5,5 cm longis, foliis brevioribus, breviter non connatis apice, strobilis masculis ellipsoideis, pedicellatis, plerumque longioribus, diametro minore, bracteis exterioribus, connatis per 1/2–3/4 longitudinem, bracteis interioribus angustioribus, perianthio obovato, angustiore, synangiophore longiore, strobilis foemineis pedicellatis, ellipsoideis, bracteis plerumque plures, bracteis interioribus longioribus, diu connatis, ovulo diu exserto e bracteis, micropyles tubo breviore, fructifero strobilo majore, ovoideo vel globosoovoideo, bracteis maturis semper luteo-aureis, seminibus majoribus, circiter 3 mm e bracteis exsertis.

Description: —Dioecious subshrub, erect, 40–60 cm tall, old stems woody, erect or procumbent, bark greenish-gray. Twigs erect to divaricate, fasciculate and loosely inserted at the nodes, yellowish-green, cylindrical, finely furrowed and scabrous along the ribs, (1) 1.5–2.5 mm in diameter, heartwood red-brown; internodes 1.5–5.5 cm long. Leaves opposite, 1–1.3 mm long, membranous, fused for most of their length, briefly free and not recurved at the apex, each with an acute green triangular rib on the back and a coriaceous basal ring; turning brown and lacerate at maturity. Male cones ellipsoid, 3.5–6.5 mm long, 2–2.5 mm in diameter, pedicellate, with pedicel 1.5–2.5 mm long, usually opposite; bracts binate in 3–7 pairs, ovate, acute, connate per 1/2–3/4, 1– 1.5 mm long, 1.4–1.5 mm wide, outermost ovate, innermost late obovate; perianth exserted from the subtending bract, obovate, 1.6–1.9 mm long, deeply bilobed; synangiophore 2–3.2 mm long, long exserted from perianth, with 5–10 synangia, sessile, densely aggregated at top. Female cones uniovulate, ellipsoid, opposite or 3-clustered, 6–7 mm long, 2.5–3.5 in diameter, petiolate, with petiole 2.5–3 mm long; bracts smooth at margins, connate, in 3–4 pairs, broadly ovate, obtuse at apex, green and membranous in the edge, connation ranging 3/ 4 in lower bract, 1/2–1/ 3 in middle bract and 4/5–7/ 8 in upper bract; lower bract 1.5–3 mm long, middle bract 3–4.5 mm long and upper bract 6–6.5 mm long; ovule ca. 4 mm long, ellipsoid, shortly exserted from bracts; micropylar tube straight, ca 2.5 mm long, exserted 0.5–1 mm from upper bract. Female cone at maturity ovoid to globose-ovoid, 7–8 × 4.5–5.5 mm, with bracts yellow-gold. Seeds 6–6.5 × 3–3.2 mm, blackishbrown, slightly striated longitudinally, long ovate, plane-convex, exserted 0.5–1 mm from bracts.

Etymology: — The specific epithet means golden and refers to the colour of the ripe bracts in female cones.

Phenology: —It is a dioecius plant flowering in April and producing seeds from June to July.

Seed micro-morphology:—In order to verify if there are significant differences regarding the micro-sculptures of the seed testa of Ephedra aurea compared to E. nebrodensis , a SEM investigation was carried out on these species. On the basis of this research, remarkable morphological differences were found when comparing the two species. In particular, the seed coat of Ephedra aurea is characterized by longitudinally rectangular cells, rugose, 170–250 × 28– 35 μm, bordered by a prominent reticulum. The anticlinal walls are quite raised, while the periclinal ones are flat (Fig. 5A). The populations of E. nebrodensis show a seed testa characterized by shorter fusiform cells, slightly scabrous, 90–180 × 17–21 μm, delimitated by slight furrows. The anticlinal walls are furrowed, while the periclinal ones are flat or slightly convex, irregularly covered by minute papillae (Fig. 5B). These ornamentations are very similar to those of the seeds of this species coming from Morocco investigated by Ickert-Bond & Rydin (2011, Fig. 2 D,H, L,) and identified by them as Ephedra major .

Pollen morphology:—According to literature ( Iversen & Troels-Smith 1950; Welten 1957; Steeves & Barghoom 1959; Zavada & Gabarayeva 1991; Ickert-Bond et al. 2003; Punt 2007; Norbäck Ivarsson 2014; Bolinder et al. 2016; Bolinder 2017; Khan et al. 2018), all Ephedraceae , as well as Welwitschia , are characterized by a type of pollen grain which differs from that of the rest of the Gymnosperms and for this reason is known as ephedroid pollen. In particular, it is classified as polyplicate, with an equatorial view perprolate, rarely prolate, while the polar shape is interlobate. The ornamentations of the surface are verrucate with sculpturing rugulate. This pollen grain shows more than meridional ridges (plicae) separate by deep furrows, which can be either branched or unbranched and are called pseudosulci (Huynh 1975, Bolinder et al. 2015), since they look very similar to sulci. Indeed, the pollen of Ephedra is usually treated as inaperturate, as the exine is much thinner than over the ridges and neither the tectum nor the infratectum occur (Steeves & Barghoorn 1959; Kedves 1987; El-Ghazaly et al. 1998; Bolinder et a. 2015). According to Bolinder et al. (2016, Fig. 1) three different types of pollen can be distinguished, such as: A) pollen with unbranched pseudosulci, having a significantly higher number of plicae, usually 10–18, with a smaller size; B) pollen with pseudosulci with first order branched, having a lower number of plicae (4–8, rarely 10) showing a size slightly larger; C) similar to type B, but with pseudosulci with first and second order branching. Current knowledge based on paleopalynogical records regarding the morphological diversity of Ephedra ( Ickert-Bond et al., 2009; Rydin et al., 2010; Bolinder et al., 2015, 2016) emphasized that the type A pollen is more ancestral than types B and C ones, noting an intrinsic relationship between the pollen form and pollination syndromes. In fact, pollen with unbranched pseudosulci is linked to insect-pollination, which represents the more ancestral reproductive strategy in Ephedra , but does also occur in some presumably wind-pollinated species ( Bolinder et al. 2016). Pollen grains of types B and C occur are far as known always associated with anemophilous pollination ( Bolinder et al. 2016). The polyplicate pollen grains of Ephedra are very similar to those of Welwitschia , but the latter differ in being monosulcate with a single and broad sulcus, whereas Ephedra pollen is inaperturate with psedosulci. According to Doyle & Donoghue (1986), aperturate monosulcate pollen is considered ancestral in the Gnetales , while polyplicate inaperturate pollen is interpreted as derived. Micromorphological investigations carried out on pollen grains of Ephedra aurea and on those of the closely related E. nebrodensis emphasized that they are very different in size and shape. In particular, E. aurea shows pollen of type A, characterized by 11–12 plicae, very compact and acute on the back, ca. 4 μm high,, with unbranched and linear line in the groves (corresponding to pseudosulci), the absolute size (equatorial lenght and diameter) is 43–48 × 17–20 μm (Fig. 6A). As regards to the pollen of the Sicilian populations of E. nebrodensis , it is quite similar to that already known of other Mediterranean populations of this species previously analyzed by other authors ( Welten 1957; Steeves & Barghoorn 1959; Norbäck Ivarsson 2014). The pollen of this species is of type C, with 5–7 plicae, quite spaced and rounded on the back, 6–6.5 μm high, rather smooth on the surface, with first and second order branches on the pseudosulci, which are very irregular, the absolute size is 46–50 × 20 μm (Fig. 6B). Therefore, these two species, basing on the pollen peculiarities, are completely differentiated not only morphologically, but also from an evolutionary point of view. In fact, as already highlighted, E. aurea has an ancestral type of pollen that may involve insect-pollination, while in E. nebrodensis the pollen represents a derived type which is linked to wind-pollination.

Distribution and ecology: — Based on current knowledge, Ephedra aurea occurs in north-western Sicily and particularly along the western slopes of the Capo San Vito peninsula, with a well circumscribed population localized at Isulidda, near Macari village, as well as in the calcareous slopes of Mt. Cofano, Mt. Erice and in Contr. Castellazzo near Castellamare del Golfo. In these stands, it grows on the see-facing cliffs, constitute by Mesozoic limestones (Fig. 7). In fact, it is a true chasmophyte, linked to rocky crevices, where it is represented by several male and female individuals (Fig. 8). Usually, it is a member of a thermophilous rupestrian plant community belonging to the Dianthion rupicolae, syntaxon described by Brullo & Marcenò (1979). The vegetation in which E. aurea occurs is characterized by several other endemic or rare species, such as Brassica villosa Bivona (1816: 20) subsp. brevisiliqua (Raimondo & Mazzola in Mazzola & Raimondo 1997: 834) Raimondo & Gerace (2003: 441), Dianthus rupicola Bivona (1806: 31) subsp. rupicola , Lomelosia cretica ( Linnaeus 1753: 100) Greuter & Burdet in Greuter & Raus (1985:74), Centaurea panormitana Lojacono (1903: 137) , Helichrysum panormitanum Tineo ex Gussone (1844: 467) subsp. panormitanum , Euphorbia bivonae Steudel (1840: 610) , etc.

Conservation status: − Based on current knowledge of its distribution in Sicily, Ephedra aurea represents a rare chasmophyte circumscribed to very few carbonatic rocky stands of north-western Sicily. It seems represented by no more than one hundred mature individuals, distributed in a very limited area and, therefore, it has to be considered as threatened species. This shrub, growing in rocky habitats together with several other rare and taxonomically isolated species, does not seem usually threatened by anthropogenic disturbance, but only by occasional fires. Therefore, following the criteria laid out by IUCN (2019), Ephedra aurea for its restricted range and low number of individuals, is assessed as “Critically Endangered” (CR B2a).

Taxonomic remarks: —From the taxonomical point of view, Ephedra aurea is closely related to E. nebrodensis sharing twigs finely furrowed and scabrous along the ribs, synangiophore exerted from perianth, bearing several sessile synangia at the top, female cones uniovulate, 2–3 at the nodes, 6–7 mm long, micropylar tube straight, but they differt in several significant features regarding the vegetative and reproductive structures. In particular, E. nebrodensis differs from E. aurea in twigs fastigiate, compacted, dark-green (versus twigs divaricated, loosely inserted, yellowishgreen),with internodes 1–2 cm long and 0.4–0.7 mm in diameter (versus 1.5–5.5 mm long and (1) 1.5–2.5 mm in diameter), leaves 2–3 mm long (versus 1–1.3 mm long), free for c. 1/3 of their length (versus fused for most of their length and briefly free at the apex), male cones subsessile (versus pedicellate), ovoid, 4–4.5 mm long (versus ellipsoid, up to 6.5 mm long), with 2–6 pairs of bracts (versus 3–7 pairs of bracts), outermost connate for 1/2 of their length (versus for 1/2–3/4 of their length), innermost 2–2.2 mm wide (versus 1.4–1.5 mm wide), synangiophore 1.2–2.2 mm long (versus 2–3.2 mm long), female cones sessile to short petiolate (versus long petiolate), ovoid (versus ellipsoid), with 2–3 pairs of bracts (versus 3–4 pairs of bracts), innermost 5–6 mm long (versus 6–6.5 mm long), connate 1/3–1/2 of their length (versus connate 4/5–7/8 of their length), ovule long exerted from bracts (versus shortly exerted from bracts), micropylar tube ca. 3 mm long (versus 2.5 mm long), female cones at maturity globose (versus ovoid to globose-ovoid), 3–5 × 3–5 mm (versus 7–8 × 4.5–5.5 mm), with bracts usually red-orange or rarely yellowish (versus always yellow-gold), seeds ellipsoid (versus long ovate), 4–6 × 2 mm (versus 6–6.5 × 3–3.2 mm), exserted ca. 3 mm from the bracts (versus exerted 0.5–1 mm from the bracts). Other remarkable differences between the two species regard the micro-sculptures of the seed testa and the pollen shape. A detailed comparison between these structures has already been threaded in detail, from which it can be deduced that the two species are well distinct also in their reproductive strategies. Besides, due to its robust habit, twigs lax and divaricate with article 3–5 mm long, female cones uniovulate, usually long pedicellate, at maturity ovoid to subglobose and sometimes with yellow bracts when ripe, E. aurea is close to E. procera , a species distributed mainly in the eastern Mediterranean up to the Himalayas. However, a lot of relevant features allow to distinguish very well the two species from each other. Morphologically, E. procera differs from E. aurea in having twigs thinner and slender, smooth, leaves up to 3 mm long, fused up to 2/3 of its length, divaricated at the apex, male cones subglobose, perigon late ovate, synangiophore included in the perigon or slightly exserted, female cones solitary, with 2–3 pairs of bracts, innermost bracts 3–5.5 mm long, fused for 1/2 of their length, bracts reddish or sometimes yellowish when ripe, ovules fusiform 4.5–6.5 mm long, long exerted from the bracts, seeds oblong-ovoid, ca. 5 mm long. Another species quite related to E. aurea is E. equisetina , distributed from Caucasus to central and northern Asia, which in literature is treated also as E. nebrodensis subsp. equisetina (Bunge) Greuter & Burdet in Greuter et al. (1984; 278). This species is well differentiated from E. aurea in having twigs glaucous-pruinose in tufts, with internodes 1–3 mm long and 1–1.5 mm in diameter, leaves brownish, 1.5–3 mm long, fused for ca. 3/4 of their length, male cones solitary or in clusters of 2–4 at nodes, bracts in 3–4 pairs, fused for ca. 1/3 of its length, synangiophore slightly exerted from perianth, female cones elogated-ovoid, 8–10 mm long and 4 mm in diameter, bracts in 2–3 pairs, innermost ones 3.7–6 mm long, fused for 1/2–2/3 of its length, bracts reddish or sometimes yellowish when ripe, ovule fusiform, 4–5 mm long, long exerted from the bracts, micropylar tube geniculate.

Additional specimens of Ephedra aurea examined (Paratypes): — ITALY. Sicily: Trapani, Penisola di San Vito lo Capo , versante costiero occidentale in località “Isulidda” a Nord di Macari , 50 m di altitudine, 38°08’44” N, 12°44’09”E, 4 June 2017, S. Cambria s.n. ( CAT!) ; ITALY. Sicily: Trapani, Penisola di San Vito lo Capo, versante costiero occidentale in località “Isulidda” a Nord di Macari, 50 m di altitudine, 38°08’44” N, 12°44’09”, 8 May 2016, S. Cambria s.n. ( CAT!) ; San Vito Lo Capo (TP), 8 July 1986, S. Brullo, P. Minissale & G. Spampinato s.n. ( CAT!) ; Sicily: Trapani, Monte Cofano , versante orientale, 35 m di altitudine, 38°06’ 27”N, 12°40’ 59” E, 2 July 2012, S. Brullo & V. Ilardi s.n. ( CAT!) ; Monte Cofano-Trapani , May 1975, S. Brullo s.n. ( CAT!) ; M. Cofano , 22 July 1979, S. Brullo s.n. ( CAT!) : Castellamare del Golfo , rupi, 9 June 1988, P. Minissale & G. Spampinato s.n. ( CAT!) ; Castellamare del Golfo (TP), rupi calcaree, 20 April 1990, S. Brullo, P. Minissale, G. Siracusa & G. Spampinato s.n. ( CAT!) ; Monte Erice , 20 April 1990, S. Brullo, P. Minissale, G. Siracusa & G. Spampinato s.n. ( CAT!) ;

Specimens of Ephedra nebrodensis examined: — ITALY. Sicily: Madonie, Colma Grande nella vallata che scende alle favare d’Isnello (sub E. nebrodensis ), s.d., s.l., (NAP! Collection “Gussone - Sicilia ”); Madonie, Giugno, s.l., (NAP! Collection “Gussone - Sicilia ”); Madonie, June 1888, Ross s.n. (PAL!); Colma Grande, May, s.l. (PAL!); Isnello, in elatioribus montosis, s.d., s.l. (PAL!); Scalamadagio, 6 June 1830, s.l. (PAL!); Madonie, June 1873, Citarda s.n. (PAL!); Madonie, Pizzo Carbonara, rupi di Colma Grande, 26 August 2020, S. Cambria s.n, (CAT!); Sopra Monte Cuccio, s.d., Todaro s.n. (PAL!); Monte Cuccio presso la cima, 997 m, affioramenti calcarei, 9 May 2020, S. Cambria s.n. (CAT!); Sardinia: Oliena (Sardaigne, prov. Nuoro), Supramonte di Oliena, prés du sommet de la punta sos Nidos, alt. 1200–1250 m, dans una petite vallée à 0,5 km du sommet, 2 June 1988, Cuccuini & Luccioli 13931 (P! 01633736); Sardinia, s.d., Moris s.n. (P! 01633268). SPAIN: Huéscar Sierra de Moncayo Prov. Granada, Hab. Calcareous soils, 22 June 1988, 1st Iter Mediterraneum of Optima (PAL!-GR 065069); Sierra de Baza, Santa Barbara, Prov. Granada, Altim. 2000–2200, Hab Dolomitic and Calcareous soils, 21 June 1988, 1st Iter Mediterraneum of Optima (PAL!-GR 064952); FRANCE: Roches calcaires de Millau à Creyssels (Aveyron), fl. 23 May 1888, fr. 11 September 1888, Abbé H. Coste, s.n. (PAL!);Aveyron: Creissels, prés de Millau, fentes de roches calcaires; alt. 450–500 métres, fl. 25 May, fr. 7 August 1890, Abbé H. Coste 2581 (PAL!); Parmi le rochers élevés des Alpines (Bouches-du-Rhône), 20 May 1867, H. Roux 3901 (P! 01582711); Sisteron, Basses Alpes, 28 April 1869, Burle 136 (P! 01582711); Rochers des Dentelles à Baumes Vancluse. 30 June 1877, Reverchon (P! 01582715); Environ de Gison prés Crest, April 1877, Pilugone (P! 01582718); Montagne du Luberon, Vallon de Légarde (commune de Meridol, Vancluse), May 1866, Achintre (P! 01582719); ALGERIA: Kerrata, lieux arides et rocheux, sur le calcaire, 800 métres, rare, July 1897, Reverchon 94 (P! 01621672); Djelfa (Algérie, dép. Djelfa), flanc nord du Kef Haouas, prés du sommet, au N du Djebel Senalba,à environ 15 km à l’W de Djelfa, alt. env. 1300 m, fissures de rochers, 31 May 1984, A. Dubuis 12046 (P! 011636314); In monte Touggour prope urbem Batna in rupibus calcareis, 200 m, 21 May 1924, Maire s.n. (P! 01655682). MOROCCO: Moyen Atlas: Bekret , gorges calcaires de l’Ainengous, 1850 m, 1 June 1924, E. Jahandiez 508 (P! 01636153); Grand Atlas Oriental Ari Ayachi, escarpments rocheux, 29 June 1923, H. Humbert s.n. (P! 01655687); Imlil (Asni), Haut Atlas , rocaille, 2200 m, 14 July 1980, J. Lewalle 9642 (P! 01655683). TUNISIA: Djebel Tioucheha, May 1887, A. Letourneux (P! 01655637).

Specimens of Ephedra procera examined:— UKRAINE: In planitie territorii Elisabethopoleos.Flora Transcaucas. , 1844, Dr.Kolenati 1236 ( P!00738842); ibid( P!00738843); Elisabethopoleos, 1844, Kolenati ( P!00738844) ; GEORGIA: Davit Gareji , at caves, grassland steppe, 1032 m, 8 August 2009, J. Mitchell, R. Brown & J. Harper 35 (E00360804); Samtskhe-Javakheti, valle del río (Mtkvari), alrededores del castillo de Khertvisi, a 11 km. de Aspindza, 41° 28’ N 43° 17’ E, L. Muñoz Centeno, X. Giràldez, M. Martinez Ortega s.n. (MA763869) ; TURKEY: Erzurum, carretera para Erzurum (nº 925-04), 8km antes do Porto Gölyurt Geçidi , 40° 22’ N 40° 47’ E, 29 June 2001, S. Nisa et al. 978 (MA689532) ; Ak dag, Gümüshane, matorral, 39° 56’ N 39° 25’ E, 1 July 2001, J. Aldasoro et al. 2570 (MA690144) ; RUSSIA: Caucasus, Stavropol Krai, Karachay-Cherkessia & Kabardino-Balkaria, Karachay-Cherkessia, Karachaevskii raion, 18 May 2007, A.S. Zemov 5863 (MW0642857); Caucasus, Stavropol Krai, Karachay-Cherkessia & Kabardino-Balkaria, Karachay-Cherkessia, Habezskii raion, 12 May 2007, A.S. Zemov, 5788 (MW0642856) ; ARMENIA: prov. Vayots Dzor. río Darb, próximo al cruce de carreteras hacia Dyermuk , substrato vulcanico, 39° 41’ 43’’ N, 45° 34’ 04’’ E, 1394 m, 28 June 2005, A. Quintanar et al. 1638 (MA743775) ; prov. Syunik, pr. Kafan , roquedos vulcanicos, 39° 12’ 18’’ N, 46° 27’ 41’’ E, 710 m, 26 June 2005, R. Gonzalo et al. 209 (MA743120) ; Kotyak province, area W Abovyan, Gegham Mts. Above churches Poghos and Petros , 40° 16’ 33’’ N 44° 42’ 10’’ E, 3 July 2003, G. Fayvush, K. Tamanyan, H.Ter-Voskanian & E. Vitek 03-0673 (MA742677) ; Gegharkunik province, Chambarak distr., area NE of lake Seban, Artanish peninsula 2,5 Km ESE village Shordzha , 45° 18’ N 40° 30’ E, 15 June 2002, E. Vitek 02-276 (MA710230) .

Specimens of Ephedra equisetina examined:— KAZAKHSTAN: Almaty Oblast (Region) Kerbulak Subregion; Altyn-Emel State National Park .; Sholak Mountains ; Toigak Gorge , 43° 55’ 32’’ N, 77° 52’ 10’’ E, 698 m, 25 May 2008, D.A.H. Rae, M. F. Gardner & N. Ogar 88 (E00282033); Zaisan depression, valley Kusto clay - road metal ravine, 22 June 1997, I.O. Baitulin, N.K. Arallaev, S.G. Nesterava s.n. (MO5738145) ; RUSSIA: Siberia, Altai & Sayany Mountains, Tuva, Tandinskii raion, 51°11′N 94°14′E, 15 June 2002, I. Artemov 75 (MW0165862) ; TURKMENISTAN: Western Kopet Dag, in the mountain Balkhan Major, in the canyon Dam-Dam , on stone slopes, 20 May 2001, Kurbanov 644 (MO5603312) ; KYRGYZSTAN: Osh Region, 8 kilometers southeast of Aravan, Elevation about 1020 meters, Dry Steppe , 27 June 1999, L.R. Phillippe, J.B. Taft, C.H. Dietrich & G.A. Lazkov 30787 (E00714880); Dzhalal-Abad Region, 18 kilometer west-southwest of Kazarman, elevation about 1550 meters, mountain meadow, 15 July 2000 L.R. Phillippe, J.B. Taft, C.H. Dietrich, E. Warren & G.A. Lazkov 32146 (E007017778) .