Distinguishing features
''Vermilacinia pumila'' is classified in the subgenus ''Vermilacina'' in which it is distinguished by its small hemispherical thallus of densely compacted, erect but curved stubby branches (crowded together, touching) not more than 1 cm high, and generally 1–2 mm in diameter. This is in contrast to the taller and narrower, loosely aggregate branches (not touching) of ''V. combeoides'', 2–4 cm high, and not more than 1 mm in diameter. The branches of ''V. pumila'' are slightly inflated above the mid region, which seems related to its thinner cortex, about 50 μm thick, in contrast to the more or less uniform branch diameter of ''V. combeoides'' which has a cortex two and one-half to four times as thick (125–200 μm). ''Vermilacinia pumila'' seldom produces the terminal apothecia that is generally characteristic of ''V. combeoides''; instead, its branches frequently bifurcate into narrower lobes that abruptly taper to a pointed apex. Both species have most of the same lichens substances but notably differ in their chemotype profiles. The lichen substances include unknown terpenes referred to as T3, T4 and T5, bougeanic acid, zeorin and (-)-16 α-hydroxykaurane with salazinic acid occasionally present. The unknown T4 compound, found only in some species of subgenus ''Vermilacinia'', was present in all specimens of ''V. pumila'' studied, in contrast to not always present in ''V. combeoides''. Zeorin was often absent in ''V. combeoides'' but always present in ''V. pumila''. The T5 compound was found only in ''V. combeoides''. ''Vermilacinia pumila'' appears intermediate between ''V. combeoides'' and ''V. robusta'' by its slightly inflated branches, which in ''V. robusta'' are of similar length to ''V. combeoides'', but usually more inflated, from 1–6 mm in diameter, with a cortex about 100–120 μm thick. ''Vermilacinia pumila'' was recognized to occur in southern California, including the Channel Islands (California), Channel Islands, to just south of Tijuana in Baja California, and also on Guadalupe Island; however, its range appears to extend north to Point Lobos State Park in Monterrey County, and the thalli there may include apothecia.Taxonomic History
''Vermilacinia pumila'' was described in 1996. Prior to then, it was seen as variation of ''V. combeoides''; however, Peter Bowler and collaborators had identified the type specimen of ''V. pumila'' (before the species was described, collected by William Weber and C. J. McCoy, L-36641) from Guadalupe Island, and one other from Santa Cruz Island (collected by Rudolf M. Schuster)="Bowler1994">Bowler, P. A., R. E. Riefner, Jr., P. W. Rundel, J. Marsh and T. H., Nash, III. 1994. New species of ''Niebla'' (Ramalinaceae) from western North America. Phytologia 77: 23-37. as belonging to ''Niebla ceruchoides'' (= ''Vermilacinia ceruchoides''), which led to its treatment as a synonym in the Lichen Flora of the Greater Sonoran Desert.Bowler, P. and J. Marsh. 2004. ''Niebla''. ‘Lichen Flora of the Greater Sonoran Desert 2: 368–380 ''Vermilacinia ceruchoides'' differs in having a more intricately branched thallus with branches not more than 0.7 mm wide. The genus ''Vermilacinia differs'' from ''Niebla'' in the absence of chondroid strands, by the lack of cortical ridges that define branch margins, and by producing terpenes and bourgeanic acid not found in ''Niebla''Spjut R. W. 1995. ''Vermilacinia'' (Ramalinaceae, Lecanorales), a new genus of lichens. In: Flechten Follmann; Contr. Lichen in honor of Gerhard Follmann; F. J. A. Daniels, M. Schulz & J. Peine, eds., Koeltz Scientific Books: Koenigstein, pp. 337-351.References
External links
World Botanical Associates, Vermilacinia subgenus Vermilacinia, retrieved 29 Nov 2014, http://www.worldbotanical.com/vermilacinia_subgenus_vermilacin.htm {{Taxonbar, from=Q20720321 Ramalinaceae Lichen species Lichens described in 1996 Taxa named by Richard Wayne Spjut