Festschr. 50 jähr. Best. Preuss. Bot. Vereins 1912: 69 (1912).

Synonyms: Index Fungorum

Type: Ostpr[eussen], Cranzer Wald (Klein-Thüringen - Grenz), a. Picea u. Pinus, 12 Jun. 1909, G. Lettau (B - holotype). Evernic acid (Krog & James 1977: 22).

Thallus: pulvinate to lax, often ragged tufts, sometimes coalescing into more or less continuous swards. The laciniae are grey-green to dull green, + shining, opaque when wet, broadened from the base, flattened, internally solid or in part secondarily fistulose, medulla loosely arachnoid. Considerable variation may occur in the number and form of the laciniae, ranging from forms with a single palmate lobe to those with numerous lacerate - dissected, twisted lobes. Pulvinate forms may have lobes with extensively abraded apices so that the broken gaping ends of the pustules reveal the white medulla and the glaucous, parietal soredia. Soralia mostly developed towards the apices, lateral or subterminal, soredial development parietal, soredia released at the surface by means of lacerations or by the rupture of irregular, vesicular swellings. Apothecia extremely rare, marginal or laminal. Spores 15 - 21 / 6 µm, straight or slightly curved (Krog & James 1977: 22).

Chemistry:
Race I: Divaricatic acid confined to populations in western Europe (Krog & James 1977: 22).
Race II: Substances of the evernic acid aggregate. Occuring chiefly in eastern European populations (Krog & James 1977: 22).

Ecology: On bark.

Molecular data: Genbank

Distribution: Database

Note: Much confusion has surrounded the identity of R. baltica. The species has been persistently mistaken for R. obtusata (Degelius 1942, Ahlner 1948, Wade 1961), which also has parietal soralia released by means of more or less terminal pustules as well as containing substances of the evernic acid complex. However, Ramalina obtusata, as reported by Lettau (1912), differs in the genuine fistulose nature of the more delicate, pellucid lobes, their pale stramineous colour, and their smaller size. Furthermore, this species is characteristic of conifer twigs in moist, sheltered woodlands. The distribution of Ramalina obtusata is markedly eastern boreal, whereas Ramalina baltica is lowland temperate suboceanic (Krog & James 1977: 22).