MycoBank No.: MB628123

J. Linn. Soc., Bot. 15: 226 (1876) [1877]; type: Chile, Port Grappler, 2.xii.1868, R. O. Cunningham (E (00429965)—holotype! (or, if not, lectotype)

Siphula subtabularis Nyl. Lich. Fueg. Patag.: 3 (1888); type: Argentina, Isla de los Estados, Port John, 1882, C. Spegazzini (H (9 503 897)—holotype).

Description:

Thallus ±crustose-placodioid to subfruticose, or truly fruticose as originally described by Crombie (1876 [1877]). Composed of crowded, branched lobes, up to 1·6mm wide, but often all lobes irregularly isodiametric to shortly elongated, 0·7–2·8×0·7–1·0 mm; ivory white, matt, epruinose, convex, solid when young but soon developing a hollow interior, some lobe apices breaking open to reveal the hollow interior, inner surface rough or slightly granular and appearing sorediate.

Apothecia rare and poorly developed, observed on only two collections (Imshaug 40362, Pérez-Ortega 2631). See generic account above for description.

Conidiomata not observed.

Chemistry. K+ bright yellow, C−, Pd+ yellow,UV+ orange; thamnolic acid by TLC.

Ecology and Distribution: Endocena informis var. informis is a frequents species among other lichens and vascular plants over rocks. It  is common on the Falkland Islands. However, its range extends throughout southern Tierra del Fuego and northward along coastal Chile at least as far as Región de los Lagos (42°S). There is a distinct change in morphology along this latitudinal gradient, with collections from the west coast of Chile (including the type collection from Port Grappler, 49°26'S) having erect, subfruticose lobes, whereas those from the southern part of the range (Tierra del Fuego, Isla de los Estados and the Falkland Islands) have decumbent lobes and appear almost crustose. The two forms are sympatric at Puerto Cutter (53°22·5'S, 72°25'W) on the Brunswick Peninsula and Seno del Almirantazgo (54·56989°S, 69·13509°W) in southern Chile where both can be observed in a single collection, even appearing to be part of the same thallus. A range of intermediates also occurs indicating that only one taxon is involved, which is confirmed by the molecular data.