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Dendriscosticta wrightii (Tuck.) B. Moncada & L├╝cking (redirected from: Sticta wrightii)
Family: Lobariaceae
[Sticta wrightii Tuck.]
Dendriscosticta wrightii image

In North America, Sticta wrightii is known from British Columbia and Alaska (Goward et al. 1994), where it occupies sheltered sites at lower elevations in old-growth rainforests. Usually it occurs on conifers, although in one coastal site with Picea sitchensis, it was found on small trunks of Alnus sp. and Salix sp. Some specimens were abundantly fertile and well-developed (Fig. 8) with individual thalli measuring to more than one dm in diameter. The habitat supported many cyanolichens including free-living ‘‘Dendriscocaulon’’ sp., Fuscopannaria confusa (P. M. Jørg.) P. M. Jørg., F. ramulina P. M. Jørg. & Tønsberg, Logaria hallii (Tuck.) Zahlbr., Nephroma isidiosum (Nyl.) Gyelnik, Pseudocyphellaria anomala, and Spilonemella americana Henssen & Tønsberg.

Of particular interest were several composite thalli (Figs. 2, 9A–B) in which the dendriscocauloid cyanotypes supported typical foliose chlorotypes of S. wrightii (Figs. 9A–B). To the best of our knowledge, the existence of composite thalli in S. wrightii has not previously been reported. The phenomenon appears to be rare. The composite specimens are sterile and support chlorotypes to 1–2 cm in diameter. Small chlorotype lobes are attached to the cyanotype branches ‘‘edge-on’’ by a small marginal stalk (Figs. 9A–B); they thus represent secondary outgrowths. The cyanotypes have faintly hairy, terete to slightly flattened main branches; rhizines are lacking, but a few weakly developed pits were observed. Nevertheless, free-living ‘‘Dendrisocaulon’’ specimens growing intermixed with the composite thalli have more distinctly flattened main branches and pits. The surface hairs are short and beadlike, with constricted septa. The upper and lower cortices reacted negatively with K. TLC yielded no substances.