Halecania lobulata
Halecania lobulata is a species of crustose lichen in the family Leprocaulaceae. The lichen forms small rosettes up to 5 mm across that grow over other crustose lichens on calcareous rocks, with a greyish to yellowish-brown surface that breaks into tiny leaf-like lobes at the margins. It produces isousnic acid and related compounds that give a yellow reaction when tested with potassium hydroxide solution. The species is known from North Korea and South Korea, where it grows on exposed rock outcrops in mixed forests and near waterfalls.
Taxonomy
Halecania lobulata was described as a new species in 2005 by Pieter van den Boom and John Elix, as part of their study of rock-dwelling Halecania from Asia; in that paper they introduced both H. lobulata and H. pakistanica, noting that the former is also lichenicolous. The type specimen of H. lobulata was collected by Siegfried Huneck in 1986 on a near-vertical granite wall beside a waterfall in the Isoonam-Tal, Mount Myohyang, where it was growing over crustose lichens allied to Hymenelia; the holotype is deposited in the Graz herbarium.Within Halecania, the species is characterised by its small, rosette-forming, distinctly thallus and its lichenicolous habit on Hymenelia on calcareous rock. In overall appearance it resembles species of the genus Solenopsora, but van den Boom and Elix pointed out that H. lobulata is readily distinguished by its halonate, single-septum ascospores and by its chemistry.
Description
The thallus of Halecania lobulata forms small, tightly attached rosettes up to about 0.5 cm across and a few tenths of a millimetre thick. The centre is cracked to, breaking towards the margin into small, leaf-like that are flat to slightly convex and often slightly raised at the tips. The upper surface is smooth, matt to faintly shiny and greyish to yellowish brown, becoming a little paler when wet, and lacks a distinct upper. In section, the upper part of the thallus is made up of dark brown fungal hyphae containing many tiny refractive, especially around the apothecia.The is diffuse, with green algal cells filling most of the upper thallus, while the underside is pale brown and composed of loosely interwoven hyphae, sometimes bordered by a dark bluish-black. Apothecia are usually common near the centre, small and closely attached, with dark brown to almost black, non-pruinose surrounded by a thin, pale yellowish-brown. The asci are of the Catillaria type and contain eight oblong-ellipsoid, 1-septate ascospores, each surrounded by a gelatinous that swells in potassium hydroxide KOH solution. Tiny immersed pycnidia produce short rod-shaped conidia, and chemically the thallus gives a K+ reaction and contains isousnic acid as its main lichen product, together with smaller amounts of atranorin, confluentic, stictic and cryptostictic acids.