The Brvologisl 99(4), pp. 401-406 Copyright © 1996 by the American Bryological and Lichenological Society, Inc.

Didymodon sicculus sp. nov. (, ) from the Iberian Peninsula

M. J. CANO, R. M. Ros, P. GARCIA-ZAMORA, AND J. GUERRA Departamento de Biología Vegetal (Botanica), Facultad de Biología, Universidad de Murcia, Campus de Espinardo, 30100 Murcia, Spain. E-mail: [email protected]

Abstract. Didymodon sicculus sp. nov. is described and illustrated from southeastern Spain where it occurs on saline and gypsiferous soils. The new species is similar in habit to D. luridus Spreng., but differs in having leaves with smaller upper cells, rectangular basal cells, margins recurved from near the apex to the base, and quite papillose laminal cells.

For the last several years, we have been studying culus comes from the latin siccus and indicates that the bryophyte flora and vegetation of southeastern the grow in dry habitats. Spain, and many samples of a taxon macroscopi• cally similar to Didymodon luridus Spreng. were TYPE: SPAIN. ALICANTE.Calpe, salinas El Saladar, UTM: BC 4481, Cano & Ros, 15.III.l993, MUB5510, ho• collected in the provinces of Alicante and Almena. lotype, SPAlN. ALICANTE.Sierra de la Solana, near Bal• We have concluded that these samples correspond seret (Bañeres), UTM: XH 9890, 760 m, Cano (MUB to an undescribed taxon. 5543); Sierra de Aitana, Barranco del Arc (Sella), YH 4078, 500 m, Cano (MUB5540 and 5542); Peñon de Ifach DIDYMODON SICCULUS Cano, Ros, García-Zamora, (Calpe), BC 4580, 100 m, Cano & Ros (MUB5545); near L'Olla (Altea), YH 5969, 50 m, Cano (MUB5539); Cabo Guerra (FIG. & J. sp. nov. 1-20) Azul (Campello), YH 2755, O m, Cano & Ros (MUB5544); near La Font (San Juan de Alicante), YH 2554, 10 m, Species dignoscenda phyllidiis papillosis, quorum api• Cano & Ros (MUB5546); Cerro de la Sal, near Caserío cales cellulae sunt 6-14 /-lm latae, parietibus incrassatae Los Purgateros, XH 7350, 750 m, Cano & Guerra (MUB atque nonumquam bistratae, cellulae autem basilares, 5551); Laguna del Hondo, Azarbe del Riacho (Crevillen• longe rectangulae. te), XH 9528, Cano & Ros (MUB5547); Laguna del Hon• do, XH 9730, 15 m, Cano (MUB5550); Laguna del Hondo, Plants olive-green or brownish, forming small Vereda de Sendres (Elche), XH 9829, O m, Cano & Ros turfs; stems erect, simple, not tristichous, some• (MUB5549); Laguna del Hondo, XH 9927, O m, Cano & times branched, up to 2 mm high; rounded in trans• Ros (MUB5548); Lagunas de Santa Pala, Elche-Guardamar verse section, hyalodermis absent, sclerodermis and del Segura road (Elche), YH 0428,5 m, Cano & Ros (MUB 5541); Lagunas de Santa Pala, north road of lagoon (El• central strand scarcely differentiated; leaves more che), YH 0429, O ID, Cano & Ros (MUB5558); Torre de or less imbricate when dry, erect-patent when la Horadada, Las Villas (Pilar de la Horadada), XG 9692, moist, concave, ovate, 0.7-1.2 mm long, 0.3-0.6 O m, Cano (MUB5538). ALMERIA.Sierra del Cabo de Gata, mm wide; lower leaves shorter than upper; apex Barranco Pollatos (Níjar), WF 7567, 100 m, GarGÍa-Za• mora & Ros (MUB5641); Sierra del Cabo de Gata, Playa rounded to acute; margins entire, papillose-crenu• de los Genoveses (Níjar), WF 7866, O m, GarGÍa-Zamora late, usually recurved up to 34 of leaf length, base & Ros (MUB5642); Sierra Alhamilla, Las Palomas (Ta• slightly decurrent; costa stout, 50-60 fLm wide at bernas), 1200 m, WF 6295, GarGÍa-Zamora & Ros (MUB leaf base, ending in or below apex, sometimes 5643).-All paratypes. shortly excurrent, strongly papillose at back; costa in transverse section with 2-5 guide cells in one Habitat.-Didymodon sicculus occurs on dry, layer, one band of ventral and orte of dorsal non• loamy, saline, or gypsiferous soils, in markedly xer• stereid-cells, and occasionally a group of stereids ophytic communities of the order Tortulo-Aloine• dorsal to the guide cells; ventral cells of the costa talia bifrontis (Ros & Guerra 1987), associated with quadrate, sometimes short-rectangular at middle other pottiaceous genera such as Acaulon, Aloina, part of leaf; lamina cells papillose, with 1(-2) pa• Crossidium, and Pterygoneurum. This species has pillae per cell, ventral part of the leaves less papil• been collected in communities of the Pottio-Riccion lose than the dorsal; upper and median cells ± crustatae and the Aloino-Crossidion crassinervis al• rounded to irregularly quadrate, occasionally bistra• liance. The former includes associations developed tose, with thick-walls; basal cells rectangular, up to on dry saline or temporarily f100ded soils (some of 50 fLm long, papillose and with thick-walls; peri• the characteristic species of this alliance are Pottia chaetial leaves longer than vegetative leaves, 1.0• pallida, Riccia crustata, and vahliana). The 1.6 mm long, 0.4-0.6 mm wide, often with rounded second includes communities occurring on clay, apex and evanescent costa. Probably dioicous; male loamy-limestone, and gypsiferous soils (character• plants and sporophytes unknown. The epithet sic- istic species are Acaulon dertosense, Crossidium 0007 -2745/96/401--406$0.75/0 -+02 THE BRYOLOGlST [VOL. 99

3. Leaf apex. - 4. Upper 7. Basal CANO ET AL.: DIDYMODON SICCULUS SP. NOV . 403

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9-14. Didymodon siccu/us. - 9. Vegetative leaf. - 10. Perichaetialleaf. - 11. Median Jeaf cells. - 12. ~chaetiaJ leaf. - 13. Marginal basal1eaf cells. - 14. Median leaf cells towards margino All from holotype. = 160 ¡.un; 11-14 = 20 [.Lm. 404 THE BRYOLOGIST 19961 CANO ET AL.: DIDYMODON SICCULUS SP. NOV. 405

luridus, one being related to D. vinealis (Brid.) Zand. but having ver y short leaves (treated by Zan• der as D. vinealis varoluridus (Spreng.) Zand.], and another being related to D. tophaceus but having quadrate ventral costal cells and grawing in dry habitats", which we interpret as D. sicculus. Another taxon with intermediate characters be• tween D. luridus and D. tophaceus, therefore relat• ed to D. sicculus, is Barbula trifaria (Hedw.) Miu. varo desertorum (Fraehl.) Agnew. It is known from Iraq, Saudi Arabia, and Yemen Arab Republic (Frey & Kiirschner 1991) on sandy soils, and can .. be distinguished from the other three by short, shortly acuminate leaves with bistratose apices (Agnew & Vondrácek 1975). The American spe• FIGURE 21. Dislribulion of Didymodon sieeu/us on the cies, Didymodon brachyphyllus (Sul!.) Zand. (illus• Iberian Peninsula. trated in Zander 1994), is also similar to D. siccu• lus, but the former can be differentiated by its shorter leaf basal cells (4-14(-20) [Lm), that are crassinerve, Dicranella howei, and Pottia davalli• usually transversaly elongated, acute leaf apices, ana). and upper laminal cells and abaxial costal cells con• The new taxon is distinguished by leaves with spicuously papillose. The recently described Didy• papillose cells; thick-walled upper laminal cells (6• modon nevadensis Zand. (Zander et al. 1995) fram 14 [Lm wide), occasionally bistratose leaves, rect• southern Nevada (U.S.A.) occurs also on gypsum angular basal cells and leaf margins recurved fram soils, but can be differentiated fram D. sicculus by near the apex to the base (Table 1). This set of cucullate leaf apices, the presence of a costal pad, characters is not present in D. luridus (Demaret & and asexual repraduction by tubers. Castagne 1964; Smith 1978; and Nyholm 1975). Nevertheless, some of the characters of Didymodon ACKNOWLEDGMENTS sicculus can be found in (Brid.) Lisa, although in the laUer species adaxial We are graleful lO A. J. E. Smith, J. P Hébrard, and R. Zander for their valuable commenls on the specimens, and cells of the costa are long-rectangular, basal leaf lo M. Crosby for the constructive suggestions on an earlier cells longer than 50 [Lm, and the leaves notably version of the manuscript. This research was carried oul decurrent. Didymodon sicculus may be related to with financial aid frum DGICYT of Spain (Projecl PB93• D. tophaceus; i.e. however, the habitat of the lauer 1141). species is different. It occurs on vertical calcareous rack faces where water seeps or in humid places, LITERATURE CITED while D. sicculus is a terricolous species that occurs AGNEW, S. & M. VONDRÁCEK. 1975. A Flora of in dry habitats. According to Zander (in Jiu.) " ... lraq. Feddes Repertorium 86: 341-489. there are actually two taxa that have been called D. DEMARET, F. & E. CASTAGNE. 1964. Flore Générale de

TABLE 1. Comparison of Didymodon /uridus and D. sieeu/us.

Didymodon /uridus Didymodon sieeu/us

Papillae on laminal cells absent 1(-2) per cell Upper lamina! cells very thick-walled, 4-10 f.Lmwide, uni• thick-walled, 6-14 f.Lmwide, occasion• sO'atose ally bistratose Basal laminal cells quadrale 01' short-rectangular, up to 22 long-rectangular, papillose, up to 50 f.Lm f.Lm long long Leaf apex acute acute-rounded Leaf margins recurved up to 11;, of leaf !ength recurved up to 3M of the leaf length

FIGURES 15-20. Didymodon sieeu/us. - 15. Recurved margin of median part of leaf. - 16. Abaxial surface of costa at median part of leaf. - 17. Abaxial surface of costa in leaf apex. - 18. Adaxial surface of costa in median pan of leaf. - 19. Leaf transverse section. - 20. Detail of lamina cells of leaf in transverse section. All from holotype. Scales: 15-19 = 20 f.Lm; 20 = 2 f.Lm. 406 THE BRYOLOGlST [VOL. 99

Belgique. Bryophytes. VOlllme 11, fascicle lIT. Minis• SMITH, A. .l. E. 1978. The Moss Flora of Britain & Ire• tere de L Agriclllture, .Iardin Botanique de LEtat, Bru• land. Cambridge University Press. Cambridge. xelles. ZANDER, R. H. 1994. Didymodon Hedw., pp. 299-319. FREY, W. & H. KURSCHNER. 1991. Conspectus Bryophy• In A . .l. Sharp, H. Crum, & P M. Eckel (eds.), The torum Orientalllm et Arabicorum. An Annotated Cat• Moss Flora of Mexico. The New York Botanical Gar• den, Bronx, NY. alogue of the Bryophytes of SOllthwest Asia . .l. Cra• ---, L. R. STARK & G. MARRS-SMITH. 1995. Didy• mer, Stuttgart. madan nevadensis, a new species for North America, NYHOLM, E. 1975. Illustrated Flora of Nordic , with comments on phenology. THE BRYOLOGIST 98: Fasc. 2, Nordic Bryological Society, Lund. 590-595. Ros, R. M. & .l. GUERRA. 1987. Vegetación briofítica ter• rícola de la Región de Murcia (sureste de España). Phytocoenologia 15: 504-567. ms. sllbmitted Feb. 15, 1996; accepted April 25, 1996.