Crepis novoana (Asteraceae), a new species restricted to coastal cliffs in northern Galicia (northwest Iberian Peninsula)

Botanical Journal of the Linnean Society (1997), 123: 147-155. With 3 figures

Crepis nouoana (Asteraceae) a new species restricted to coastal cliffs in northern Galicia (northwest Iberian Peninsula) SANTIAGO ORTIZ F.L.S., XAVIER SONORA AND JUAN RODRIGUEZ-OUBINA F.L.S. Laboratorio de Botrinica, Facultade de Farmacia, Universidade de Santiago, 15706 Santiago de Compostela, Galicia, Spain

Received Janualy 1996, acceptedfor publication August 1996

A new species of the section Lpidosmis (Rchb.) Benth. of the genus Crepk L. (Asteraceae)is described. The new species is restricted to a single known locality on near-vertical coastal cliffs of the Ria de Cedeira in northern Galicia (northwest Iberian Peninsula). Morphometric characters permitting discrimination from the most similar taxa are detailed, and possible phylogenetic relationshipswith other species of the section LpidosetiS (particularly those of the C. vesicaria complex) are discussed. 01997 The Linnean Society of London

ADDITIONAL, KEY WORDS: -Compositae - Lactuceae - systematics - taxonomy - endemism Iberian Peninsula. CONTENTS Introduction . . . . . . . . . . . . . . . . . . . Material and methods . . . . . . . . . . . . . . . . Description . . . . . . . . . . . . . . . . . . . Crepis muoana S. Ortiz, Sofiora & Rodr. Oubiiia, sp. nou Phenology and seed viability . . . . . . . . . . . Ecology and distribution . . . . . . . . . . . . . Discussion . . . . . . . . . . . . . . . . . . . . Relationships with similar taxa . . . . . . . . . . Origin and phylogenetic relationships . . . . . . . . Acknowledgements . . . . . . . . . . . . . . . . . References . . . . . . . . . . . . . . . . . . . .

. . . . . . . .

. . . . . . . .

. . . . . . . .

. . . . . . . .

. . . . . . . .

. . . . . . . .

. . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . .

147 148 148 148 149 149 152 152 154 154 155

INTRODUCTION

In the course of a study of the flora of the northernmost part of A CoruAa Province (northwest Iberian Peninsula), we found a population of the genus Cre@ L. on the near-vertical cliffs near Vilarrube on the Ria de Cedeira. Detailed morphological study and comparison with material of similar taxa indicates that the Cedeira specimens are of a new species, which we describe below. 0024-4074/97/020147

f

9 $25.00/0/bt960078

147

01997 The Linnean Society of London

148

S. ORTIZ E T A L

SIATERIAL AND METHODS

Plant species associated with the new species were recorded. To evaluate the viability of the new species in conventional pot culture (Hartmann & Kester, 1994), a total of 80 seeds were collected and planted; of these, 40 were soaked and treated with gibberellins prior to planting. Ten plants were collected and deposited in the SANT herbarium. Specimens of similar taxa from COI, BM, K and SANT herbaria were studied. Mitotic chromosome counts were done on root tips which had been maintained in saturated PDB solution for 2 h, fixed in ethanol and glacial acetic acid (3: l), hydrolysed in HC 1 at 6OoC and then squashed in 2% acetic orcein stain.

DESCRIPTION

Crepis novana S. Ortiz, Soiiora & Rodr. Oubiiia, sp. nov. (Sect. Lepidoseris (Rchb.) Benth.) Biennis in perennem. Folia ex ellipticis ad oblanceolata, integra, dentibus marginalibus generaliter retrorsis, curvatis. INVOLUCRUM cylindrico-campanulatum (7-1 10-12 (-13) X (7-) 9-12 (-20)mm; receptaculum alveolis ciliis albis circumdatis. ACHAENIA biformia, altera fusca, 6-9 X 0.5-0.6mm, cum rostro 2.5-3.7 mm longo, disposita generaliter in interna capituli parte et altera pallida, 6.5-8 X 0.5-0.7mm, in apice attenuata, sine rostro, in capituli margine et, aliquando, in eiusdem interiore disposita.

lype. A Coruiia, Valdovifio, Ria de Cedeira, near Vilarrube. On coastal cliffs. 5.v. 1992. Sofiora s.n. ( S A N T , holotype; BM, K, MA, SANT isotypi). Biennial or perennial. HERB 18-45 cm high. ROOT 2.5-12 mm wide, often woody, thickened in its upper part and often bulbous. STEM 2.5-7 mm wide, often solitary, branched in its upper part or from the basal part upwards, striate, covered with patent glandular or eglandular setose hairs, in some areas interspersed with a very lax adpressed tomentum. LEAVES entire, with eglandular white pubescence; basal leaves (4.5-) 6-10 (-14) X (1-) 2-3 (-4.5)cm, elliptical to oblanceolate, narrowing basally mm in length, margin with 1-5 mm long teeth, to a pseudopetiole of (0.7-) 1-2 (4) these curved and often retrorse. Median leaves 18-70 X 6-35 mm, lanceolate to oblong-deltate, with base auriculate-amplexicaul, often toothed, especially in the distal third. Upper leaves 4-55 X 1-20, linear-lanceolate, bracteiform, inserted at the base of the peduncles. CAPITULA 10-40 in cymose (to corymbiform) aggregate inflorescences. Principal flowering stems, 3-6 (-8), each with 3-12 capitula on 15-60mm long peduncles. CAPITULUM (12-) 13-15 (-18) X (7-) 9-12 (-2O)mm, cylindrical-campanulate; involucre (7-) 10- 12 (- 13)mm long, with two rows of bracts which become reflexed at maturity; 7-12 outer bracts mostly situated at the base of the involucre, though some at the apex of the peduncle, (2.5-) 3-5 (-6) X (0.7-) 1-1.5 mm. 1/3-1/2 of the length of the inner bracts, lanceolate, acute to acuminate, brown to greenish, generally with a narrow scarious margin, totally glabrous or with an adpressed tomentum, white at the base and the margins, occasionally with some patent glandular hairs towards the distal extreme of the median nerve, the latter generally inconspicuous; inner bracts (1 0-) 12-1 4, lanceolate, (7-) 10-12 X (1-) 1.5-2.5 (-3.5)mm, with acute apex, greenish, with a

NEW SPECIES OF CREFIS

149

scarious margin wider towards the base, with white tomentum adpressed particularly along the margin, and with patent, black, mostly glandular hairs in the area of the median nerve; median nerve conspicuous, and somewhat carinate; axial face of inner bracts with sericeous pubescence due to short whitish hairs. Receptacle with pits ringed by white cilia 0.2-0.5 mm (long). FLOWERS (8-) 10-13 mm long, with ligulate yellow corolla; in marginal flowers, the external part of the ligule is often reddish; corolla tube 2-3.5 X 0.2-0.3mm, sometimes with short eglandular pubescence or sessile glands; ligule (4.5-) 5-6 (-7) X (0.8-) 1-1.5 (-2)mm, generally covered towards its base with a lax pubescence which may sometimes exceed 1 mm in length. Anthers 3-4 mm long, with sagittate base and obtuse tip; basal anther appendages oblong, acute, 0.3-0.5 mm long. Style-branches 1-2 mm long, green, occasionally yellowish green. ACHENES of two types: type 1 achenes typically situated in the central part of the capitulum, 6-9 mm X 0.5-0.6 mm, brown, ten-ribbed, spiculate, with a 2.5-3.7 mm beak, which is generally shorter than the 3.54.5 (-5.5) mm achene body; type I1 achenes situated at the external margin of the capitulum or at its centre, 6.5-8 X 0.5-0.7mm, pale straw yellow, gradually narrowing towards the tip, not beaked or with inconspicuous beak 0.5-1 .O mm long; pappus white, 3.5-4.5 (-5) mm, equalling or slightly overtopping the involucre, comprising 40-50 fine, soft, caducous bristles (Fig. 1). Chromosome number 2n = 8 (Fig. 2). Species named after J. G. NOVO,who provided the Latin diagnosis of this and other new taxa described by us.

Phenology and seed viabilib In the wild, flowering occurs during May. Of the 80 seeds collected, none germinated in pot trials. We are currently attempting micropropagation and germination in vitro whose results will be published in a different article.

Ecology and dirtribution We know of only one locality for the new species (see Fig. 3). This is quite possibly the only locality, since we have extensively searched the cliffs of this area without finding other populations. The known population occupies a narrow strip of terrain c. 200m in length, close to Vilarrube on the western shore of the Ria de Cedeira (a ria is a narrow estuarine bay). Within this area, the new species is chasmophytic, associated with plants such as Arm& pubkera (Desf) Boiss., Crithmum maritimum L., Linaria polygal@lia Hoffmanns. & Link subsp. aguillonensis (Garcia-Martinez) Castroviejo & Lago, Spe-rguhria rupicola Lebel, Koeleria ghuca (Schrader)DC. and Leontodon taraxacoides (Vill. MCrat. ) In terms of Zurich-Montpellier phytosociology, the new species forms part of halo-chasmophytic communities of the association CrithmoAmerietum pubkuae, which is frequent on cliffs in the northwest Iberian Peninsula (Ortiz & Rodriguez-Oubifia, 1993).In terms of the phytoclimatic zonation of RivasMartinez (1987),the new species occurs in the Eucolino sub-belt of the Colin0 (Hill) belt of the northern subsector of the Galaico-Asturiano sector (Cantabro-Atlantica province, Eurosiberian region).

150

S. ORTIZ ET-AL.

Figure 1. A, habit. B, basal leaf. C , capitulum. D, floret. E, beaked achene. F, unbeaked achene. Based on holotypus.

NEW SPECIES OF CR.EPZS

Figure 2. Micrograph of a squash preparation of Crepis chromosome number 2n = 8.

I

MUOU~U

151

root-tip cell at metaphase, showing

i

Figure 3. Map showing the single known locality for Cmpis nouoana in Galicia (northwest Iberian Peninsula).

152

S. ORTIZ ETAL.

DISCUSSION

&lationships with similar taxa The new species should clearly be included in Crepis sect. Lpidoseris (Rchb.)Benth., since (a) it is not rhizomatous, @) its capitula are in cymose aggregate inflorescence, (c) the outer involucral bracts are clearly distinguishable from the inner involucral bracts (these latter being non-imbricate and pubescent on their axial surface), (d) the receptacle is pitted, the pits being ringed by white cilia, (e) the achenes are tenribbed, of two types, some beaked, with a white pappus of 3.54.5 (-5) mm in length, and (f) chromosome number is 2n = 8. Despite the above, the new species is in some respects similar to certain species of the section Nmauchenes (Cass.) Benth., particularly Crepzi amphxijiliu (Godr.) Willk.; however, this latter is an annual species, with much smaller capitula and achenes, and with the pappus bristles arranged in a single row. These and other differences make it easy to distinguish C. nouoana from C. amphxiilia. Within sect. Lepzdoserir, the most morphologically similar taxa are clearly those which (like C. novoana) have two types of achene. Of such taxa, the most similar are C. uesicaria L. subsp. vesicaria (occurring, at the western extreme of its range, in the Mediterranean region of the Iberian Peninsula), C. vesicaria L. subsp. stellata (Ball) Babc. (from Morocco and Algeria) and C. balliana Babc. (known only from a single locality near Casablanca in Morocco, and very probably now extinct). The principal morphometric dzerences between these taxa and C. nouoana are summarized in Table 1. Note that the likewise-heterocarpic taxon C. vesicaria L. subsp. myriocephala (Coss. & Durieu) Babc., from Algeria, is morphologically very different from C. novoana, with many more capitula, these being much smaller; likewise, the number of morphological units (bracts, flowers, achenes, pappus bristles, etc.) per capitulum is smaller. Crepis novoana is readily distinguished from the various recognized subspecies of C. vesicaria, which is considered by Babcock (1947) to be an extremely polymorphic species (though this author perhaps tended to ‘lump’taxa together excessively). CrqZr novoana can principally be distinguished from the whole species C. uesicaria by the presence of pale non-beaked achenes in both marginal or central positions in the capitulum; in C. vesicaria, by contrast, such achenes are present only in marginal position. Other important morphometric differences between C. nouoana and C. uesicaria are as follows: Firstly, C. nouoana has outer bracts which are 1/3-1/2 as long as the inner bracts, while the outer bracts of C. uesicaria are only 1/4-1/3 as long as the inner bracts (except in C. vesicaria subsp. vesicaria, in which the outer bracts may be up to 3/4 as long as the inner bracts, and are in addition imbricate). Secondly, the cilia of the receptacular pits of C. nouoana are 0.3-0.5 mm long; those of C. uesicaria are only 0.1-0.3 mm long (except in the subspecies stellata and hamselerz (Boiss. ex DC.) P.D. Sell, in which the cilia are of similar length to those of C. novoana). Thirdly, the basal anther appendages of C. nouoana are 0.3-0.5mm long; those of C. vesicaria are 0.5-0.7 mm long (except in the subspecies stellatu and myriocephala, in which the basal appendages may be as little as 0.3mm long, though more commonly they are 0.5 mm long). In addition, the known population of C. novoana is outside the area of distribution of C. uesicaria as reported by Babcock (I 947). On this author’s map, C. uesicaria does

TABLE 1. Principal morphometric differences between Cqbis nuvounu and the most similar taxa. Data for C. bulliana (ofwhich only a single incomplete herbarium specimen exits, in K) are according to Babcock (1947). Data for other species are according to Babcock (194'7),Marcenb et aL (1991) and own data. OBL=outer bract length; IBL=inner bract length; RP=receptacular pit; BAA=basal anther appendage; NB=non-beaked; wrt=with respect to Characters/species Leaf shape Leafsize (cm) Involucre size (mm) Outer bract shape Outer bract arrangement Outer bract size (mm) OBL/IBL RP cilia length (mm) RF' cilia abundance BBA length (mm) Style-branch length (mm) Position of NB achenes Length of NB achenes (mm) Achene beak length wrt achene length*

C. nouoana

entire, elliptical to oblanceolate 4.5-14 x 1-4.5 7-13 x 7-20 lanceolate non-imbricate 2.5-6 x 0.7-1.5 1/3-1/2 0.3-0.5 abundant 0.3-0.5 1-2 marginal and central

C. vesicaria subsp. vesicaria

entire or partite, oblanceolate to obovate 10-15 x 2-3 a 1 4 x 4-8 ovate imbricate 4-9 x 3-5 1/3-2/3 0.2-0.3 scarce

C. vesicaria subsp. stellata

6.5-8

2-2.5 marginal 4-8

generally lyrate-pinnatipartite 9-30 x 2-6.5 a 1 2 x 4-6 linear-lanceolate non-imbricate 2-4x 1 1/4-1/3 0.3-0.5 abundant 0.3-0.5 2-2.5 marginal 4-8

shorter

equal or shorter

equal

*Data for achene beak length are for type I achenes.

0.5-0.7

C.balliana entire, oblanceolate 10 x 2.5 8x3

lanceolate non-imbricate ? 1/3 ?

? ? marginal 5-5.5

shorter

154

S. ORTIZ E T A .

not occur in the northwest Iberian Peninsula; however, it should be pointed out that C. vesicaria subsp. haenselm’ does occur in this region, though it has not been reported from any locality west of southeast Galicia (Merino, 1906; Ortiz, 1987;Jimtnez de Azcarate & Amigo, 1996).None of the heterocarpic subspecies of C. vesicaria extend anywhere near the northwest Iberian Peninsula.

Ongzn and phylogenetic relationshipJ In his exemplary 1947 monograph, Babcock argues that non-rhizomatous heterocarpic species of Crepk with a chromosome number of 2n = 8 (i.e. species of the section Lepzdoseris) are phylogenetically advanced. Babcock suggests that phylogenetically advanced restricted-range species of Crepk (particularly those of the section h’eumachenes, from the Mediterranean region) arose from lineages which originated in Central Asia and which reached the Atlantic coast towards the end of the Pliocene and the beginning of the Pleistocene. This assertion appears to be based on the fact that the Atlantic-coast endemics of the section Lepidoseris are perennial and on the assumption that the species of Lepidoserir are more primitive than the species of ,Neumachenes. However, the heterocarpy of C. nouoana, like that of C. balliana, is --- according to Babcock - an advanced character, and suggests that species of the section Lepidoseris (such as C. novoana, C. divaricata (Lowe) F.W. Schultz and C. vesicaria subsp. andyaloides (Lowe) Babc. from Madeira and the nearby islands, C. fontzna Babc. ex Maire, C. bourgeaui Babc. and C. balliana Babc. from northwest Morocco) reached the Atlantic coast via Mediterranean populations which expanded during extended cold dry periods (probably during the last glaciation) and subsequently became less viable -- in some cases to the extent of becoming extinct, as in C. balliana - when the climate became wetter. In our opinion, this hypothesis accords better with the present-day distributions of these species than the hypothesis of Babcock (1947). A similar hypothesis was recently proposed by Garcia Jacas & Susanna (1993)to explain the origins of Centaurea boim Valdks Berm. & Rivas Goday and Centaurea ultreia Silva Pando, two endangered taxa likewise restricted to very limited areas in northwest Galicia; indeed, the area of distribution of Centaurea borjae (likewise a species of coastal cliis) is very close to that of Crepk novoana. Both Centaurea borjue and Centaurea ultreiae are of the section Acrocentron (Cass.)DC., which is basically Mediterranean in distribution. The perennial strategy of the Atlantic-coast endemics of the section Lepidoseris may reflect a secondary adaptation to this region’s climate (milder and wetter than that of the Mediterranean region), and is in accordance with Babcock‘s (1947: 64) assertion that the species of this section are variable as regards the lifespan of individual plants.

ACkiOWLEDGEMENTS

We thank J.G. Novo for the Latin description, Alfred0 Lopez (Tokyo) for the illustration, and G.J. Norman for translation of the manuscript to English. The work was partly financed by the Direccion Xeral de Universidades e Investigacion, Xunta de Galicia (project XUGA 203 15B94).

S E W SPECIES OF CrnPIS

I 55

REFERENCES Babcock EB. 1947.'7ltegmus Crcpti. Pads I and II. Berkeley & I.os hgelcs: University of California Press. Garcia Jacas N, Susanna A. 1993.Cmtaureaprobngi and C. crocata in Portugal: an old confusion. NorduJoumal o j Bofany 14(1):31-38. Hvtmann HT, Keater DE. 1994. pi.opaguidn de plantar. Hincipios y prciclic.as. .?rd edirion. Mexico: Cornpaflia Editorial Continental. JimCnez de Azcarete J., Amigo J. 1996. Inventan0 doJora uarcular dos aJ7oramientos cabs de Galuia ptmdop&a c S p m t o p h y t a Cadernos da Area de Ciencias Bioloxicas (inventarios) 1 2 . 0 Castro-Sada, A CoruRa: Seminario dc Estudos Galcgos. Marcen6 C., Scidabra A., Colombo P., Melati MR. 1991.A contribution to the Crepir uesicana studics. Botanika Chronika 10:749 -760. Merino B. 1906.F h a descripfiua e ilurtrada de Galicio. II. Santiago de Compostela: Tipografia Galaica. Ortiz S. 1987.Series de vegetacion y su zonacion altitudinal en al Macizo de Pena Trevinca. Unpublished D.Phil. Thesis. University of Santiago de Compostela. Ortiz S., Rodriguez-Oubiiin J. 1993.Synopsis of the Rupicolous Vegetation of Galicia (North-western Iberian Peninsula). Folia Geobohua Phyototaronomua, A h 28: 15 49. Rivas-Mnrtinez S. 1987.Mmoni del mapa de las series de uegeh'dn de Erpalia (1: 400.000). Madnd: ICOKA, Sene thiica.