Orthotrichum handiense, sp. nov. from Fuerteventura, Canary Islands

Abstract

A new epiphytic moss, Orthotrichum handiense F. Lara, Garilleti, & Mazimpaka, is described from the Jandia Peninsula (Fuerteventura, Canary Islands, Spain). The new species is included in section Pulchella Vent. and characterized by robustness, lanceolate leaves with recurved margins, immersed capsules, stomata cryptopore located in the neck, well developed prostome, peristome of 16 teeth and 16 segments, and calyptra and vaginula densely covered with slightly papillose hairs. Drawings and SEM micrographs of the main characters are given, and possible confusion with other taxa is discussed. During spring 1992, one of the authors (M. Brugu6s) collected bryophytes in the mountainous area of the Jandfa Peninsula, from the extreme south of Fuerteventura Island, in the eastern part of the Canarian Archipelago. One of the epiphytic samples collected from the beautiful shrub Asteriscus sericeus (L. fil.) DC. corresponds to the moss described here, a robust Orthotrichum that has an exclusive set of characters differentiating it easily from any other member of the genus. The Jandfa Peninsula that gives its name to the new moss, is an area that comprises a phanerogamic flora rich in local endemics; namely, the Zarza Peak (the highest peak) is the locus classicus of, among others, Bupleurum handiense Bolle, Echium handiense Svent., Ononis christii Bolle, and Argyranthemum winteri (Svent.) Humphries. Asteriscus sericeus itself is endemic to the isle, and the most characteristic plant of the Jandia summits, where it forms the dominant scrub. Its occurrence indicates the potential area of the ancient lauroid wood, which is nowadays represented by residual, small trees like Visnea mocanera. L. fil., Maytenus canariensis (Loes.) Kunkel & Sund., and Apollonias barbujana (Cav.) Bornm. The occurrence of lauroid wood (a xeric variant of the Canarian laurisilva), as well as that of the epiphytes that grow on the shrubs, is made possible by fog persistence and horizontal precipitation owing to trade winds, however the annual rainfall average is very low around 250-400 mm (Santos, pers. comm.). At present, the Jandfa peninsula is considered a natural area under protection of the Canarian government, but it is actually subjected to strong and uncontrolled grazing pressure, mainly by goats. Only two Orthotrichum species are known from Fuerteventura O. affine Brid. and O. diaphanum Brid.; both reported by Dirkse et al. (1993) on the basis of Malme's (1988) original records. Both species were found occurring on Asteriscus sericeus, but our gatherings from this shrub at Zarza peak contained only O. diaphanum and the moss described as new here. ORTHOTRICHUM HANDIENSE F. Lara, Garilleti & Mazimpaka, sp. nov. FIGS. 1-15 Planta robusta, ramosa, filidiis lanceolatis acutis vel acuminatis, marginibus variabiliter recurvatis cellulibusque cum papillis humilibus. Capsulae ellipticae, immersae vel vix emergentes, minute sulcatae, stomatis cryptoporis in collo sitis; prostoma praesens, exostoma 16 dentibus longis papilloso-striatisque, endostoma 16 segmentis linearibus, longis papillosisque, membrana connectivali continua; vaginula et calyptra abundantibus pilis longis paulo papillosisque obtectae. TYPE: SPAIN, CANARY ISLANDS. FUERTEVENTURA. Pico de la Zarza, 760 m elev., UTM grid 28RES60, epiphyte on Asteriscus sericeus. M. Bruguds, May 1992. (BCB, holotype; MA and Universidad Aut6noma de Madrid herbarium isotypes). Plants robust, 1-2 cm tall, foliose and branched, olive-green or brown, with rhizoids restricted to lower part, in 3 cm cushions. Leaves erect to erectpatent when dry, upper ones with somewhat flexuose points; erect-patent to patent when moist; 3.00007-2745/99/619-622$0.55/0 This content downloaded from 157.55.39.249 on Wed, 03 Aug 2016 05:55:55 UTC All use subject to http://about.jstor.org/terms 620 THE BRYOLOGIST [VOL. 102