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''Niebla juncosa'' is a fruticose lichen that grows on rock, stony soil and sand along the Pacific Coast of Baja California from Punta Banda to Morro Santo Dominogo.〔Spjut, R. W. 1996. ''Niebla'' and ''Vermilacinia'' (Ramalinaceae) from California and Baja California. Sida Bot. Misc. 14〕 The epithet, ''juncosa'' is in reference to the thallus divided into rush-like branches, the stems of the flowering plant genus ''Juncus''. ==Distinguishing Features== ''Niebla juncosa'' is distinguished by the thallus divided into sublinear〔Linear—having parallel sides for 10 times or more the width, sublinear the margins not perfectly parallel, or the branches occasionally widened slightly, especially where they divide〕 subterete branches with a common attachment base (or holdfast); the primary branches generally creeping or ascending to erect, occasionally dividing into equal secondary branches and developing numerous similar branchlets along the upper side of a main branch (var. ''juncosa'') or branchlets spreading in all directions (var. ''spinulifera''), the branch margins not alternating with the cortical ridges; the whole thallus to 10 cm high and 15 cm in diameter.〔 The species (''N. juncosa'') also recognized by containing divaricatic acid, with triterpenes.〔 The cortex surrounds a fistulose to subfistulose medulla, varying from 55–175 µm thick, generally thinner on the branches where a change in thickness appears related fragmentation branchlets that break off from primary branches.〔 Two varieties recognized. Variety ''juncosa'' has primary branches with mostly entire margins〔Leaf margins. Retrieved 26 Dec 2014, http://cite.nwmissouri.edu/nworc/files/agriculture/leafid_margin/leafid_margin_print.html〕 and usually with secondary (fragmentation) branchlets that develop mostly along the upper side of a primary branch; the secondary branches break off well above the attachment to the primary branch, or nearer the apex as seen in herbarium specimens. Variety ''juncosa'' common on rocks but occasionally on sand under ''Yucca valida'' in the southern part the Baja peninsula, and on stony ground in the terricolous ''Niebla'' communities in the transition zone from chaparral to desert scrub on mesas above Punta Baja.〔 Variety ''spinulifera'' differs by primary branches with mostly wavy (lobed) margins and with spinule-like branchlets that spread in various directions from the primary branch, the spinule branchlets appear to break where attached to the primary branch, appearing to leave a rudimentary lobe; the thallus often appearing less rush-like and more mat-like related to the intricately divided branches. This variety (var. ''spinulifera'') is widely distributed throughout the range of the species.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Niebla juncosa」の詳細全文を読む スポンサード リンク
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