Phylogeny and species delimitation in Silene sect. Arenosae (Caryophyllaceae): a new section
Eggens, Frida
Jafari, Farzaneh
Thollesson, Mikael
Crameri, Simon
Zarre, Shahin
Oxelman, Bengt
PhytoKeys
2020
159
1
34
4XCHC
EB490462-58C3-5C76-A38A-E749F0598BDD
Decne., Ann. Sci. Nat. Bot. ser. 2, 3: 276. 1835, nom. cons. prop. (in press) [non Sweet].
Magnoliopsida
Caryophyllaceae
Silene
CoL
Plantae
Silene linearis
Caryophyllales
0
1
Tracheophyta
species
linearis
Type. [Egypt], Hab. le desertdu Sinai, [1.6.1832], N. Bove178(lectotype, designated here: G! [G00226732]; isolectotypes: K! [K000728452], G! [G00226733]).
Description. 15.0-60.0 cm tall, erect or spreading. Stem pubescent in lower part, scabrous, glabrous but with sessile glands in upper part; with 6-10 distinct internodes, the uppermost internode length 3.0-6.0 cm long and obviously longer than the next upper internode. Basal leaves oblanceolate 30.0-60.0 x2.0-4.0 mm, pubescent. Cauline leaves linear or lanceolate 10.0-55.0 x1.0-4.0 mm, pubescent. Calyx 11.0-19.0 mm long, campanulate at anthesis and clavate in fruit, pubescent; teeth unequal; shorter ones 1.5-2.0 mm, ovate, mucronate; longer ones 2.0-2.5 mm, ovate, acuminate; marginal hairs short (up to 0.5 mm), dense. Inflorescence non-divaricate, branch axile (much) less than 90°. Petal claws 6.0-7.0 mm long, glabrous; limbs 6.0-8.0 mm long, divided, upper-surface white, lobes linear or oblong, divergent, petal limbs cleft to middle or more, lower-surface green; coronal scales 1.0-2.5 mm long, obovate, apex dentate. Anthophore 8.0-11.0 mm long, densely puberulent. Anthers exserted; filaments 8.0-9.0 mm long, glabrous. Styles exserted. First pedicel 1.0-3.0 cm in flower, 2.0-4.0 cm in fruit, erect, glabrous, apex antrorse. Capsule 5.0-7.0 mm long, ovoid or ellipsoid, fragile, opaque. Seeds 0.7-0.9 mm wide, 0.6-0.7 mm high, testa smooth.
Distribution. E Egypt (Red Sea area, Sinai), N Arabian Peninsula, W Jordan and Palestine (Fig. 7).
Notes. Silene linearishas some superficial similarity to S. austroiranica, which has narrowly lanceolate calyx teeth with narrow transparent margin, and not the broad rounded margin of S. linearis(see Fig. 6). Silene austroiranicais allopatric and found further south and east on the Arabian Peninsula, and in eastern Iraq and western/southern Iran. The ranges of the calyx, anthophore and capsule lengths are unusually large in S. linearis. The large-flowered individuals are all found in Egypt (although not all specimens from Egypt are large-flowered), with calyx length of 17-19 mm (and proportional anthophores and capsules). The specimens are in all other respects similar (or perhaps with slightly shorter mucro on calyx teeth) to the S. linearisspecimens with smaller flowers, and we do not think the difference is sufficient to merit taxonomic recognition. The Egyptian specimens are in general (independent of flower size) tomentose to villous while the specimens from Palestine and Jordan are often slightly puberulous, although at least one specimen from Palestine is densely tomentose. One sequence for a specimen from Egypt ( S. linearis, ID 49, KX757593) is included in the ITS tree. It forms a strongly supported clade together with the other two S. linearisaccessions (PP = 1.00 MPB = 96% MLB = 93%, Fig. 3). The S. linearisclade (with the two Palestine accessions) is strongly supported in all trees (PP = 1.00, Fig. 1; PP = 0.95 MPB = 75% MLB = 95%, Fig. 4; PP = 1.00 MPB = 100% MLB = 100%, Fig. 5).
Nomenclatural notes. The name Silene linearisDecne. has been used for a long time, but the delimitation of the taxon has varied. A number of authors have used the name in our sense, e.g. Boissier (1867), Rohrbach (1868), Williams (1896), Post (1932), Chowdhuri (1957), Mouterde (1966), Zohary (1966), Chamberlain (1996)and Boulos (1999). Other authors use this name for a more inclusive taxon, e.g. Rechinger (1964)and Blakelock (1957), including S. leyseroides, S. arenosa, S. chaetodontaand S. kotschyiBoiss. (= S. microsperma). Sweet (1830)used the epithet " linearis" in Hortus Britannicus 2nd ed., in a completely different context, five years earlier than Decaisne'sdescription was published. The name Silene linearisSweet has been cited by few authors. Rohrbach (1868)referred to the name as a synonym for Silene cucubalusWib. (= Silene vulgaris(Moench) Garcke) and Marsden-Jones and Turrill (1957)recognized the name as a part of the Silene vulgaris-assemblage but used the name in a highly informal way. The name is not mentioned in Chater et al. (1993), Aeschimann (1985), Pignatti (1982)or Greuter et al. (1984). Silene linearisDecne. has been suggested to be conserved against Silene linearisSweet (Eggens & al., in press).