Strigula maritima (Lichenized Ascomycota, Strigulaceae), a New Maritime Species from Western Japan

Abstract

Strigula maritima H. Harada is described as new. It is characterized by having a ? epilithic thallus, perithecia with a blackish involucrellum, 1-septate ascospores (15-26 x 4-6 pim), and two types of pycnidia, one with 1-septate macroconidia (15-19 x 2-4 pim) and the other with simple microconidia (2-3 x ca 1 pim), and by growing on siliceous seashore rocks. It was found in the splash zone on Inno-shima Island in Seto Inland Sea, Hiroshima-ken, western Japan. The lichen genus Strigula (Strigulaceae) is represented by about 70 species (Hawksworth et al. 1995). These lichens are foliicolous, corticolous or saxicolous and mainly distributed in the tropics. In Japan, four species are known (Harada 1995, 1998): two foliicolous species, S. elegans (F6e) Mtill. Arg. and S. nitidula Mont., and two saxicolous species, S. aquatica H. Harada and S. nipponica H. Harada. In addition, another undescribed saxicolous species was collected during field trips for my taxonomic and ecological study on maritime lichens in Japan. Careful examination has revealed that it belongs to an undescribed species of Strigula. MATERIALS AND METHODS Descriptions of external morphology are based on airdried material observed under a dissecting stereoscope. Sections were made with a razor blade under a dissecting stereoscope, mounted in lactophenol cotton-blue (LPCB), and used for anatomical description and line drawings except for the color description, which was based on the GAW (glycerol: ethanol: water = 1:1:1) preparation. For observing ascus, spores, paraphyses, conidia, and conidiophores in more detail, LPCB squash preparations were used. The K, I, KI tests were conducted on sections of perithecia by using 10% KOH and/or a diluted Lugol's solution. Specimens used in this study are deposited in the herbarium of Natural History Museum and Institute, Chiba (CBM). STRIGULA MARITIMA H. Harada sp. nov. (FIGS. 1-13) TYPE: JAPAN. HIROSHIMA-KEN. Inno-shima Island in Seto Inland Sea, Innoshima-shi, Jizo-bana Point, 4 m elev., on granitic rocks in splash zone in partial shade under shrubs, 26 July 1996, Harada 16266 (cBM-FL-7354, holotype) & 16269 (cBM-FL-7357, paratype). Thallus crustaceus, ?_ epilithicus, ? continuus, cinerascens. Perithecia immersa ad basi, haud constricta ad basi, 0.3-0.8 mm lata, nigrescentes. Ascosporae 4-8 per ascus, 2-cellulae, 15-26 X 4-6 pm. Macroconidiomata et microconidiomata haud distincta extra; macroconidia 2cellulae, 15-19 X 2-4 pm; microconidia simplicia, 2-3 X ca 1 pm. Morphology.-Thallus crustose, epilithic or partly endolithic, ? continuous and with scattered