Spic. Fl. Germ.: 107 (1794).
Basionym: Lichen furcatus Huds., Fl. Angl. 458 (1762).
Type locality: Great Britain, England, South Hunts, Winchfield, W. A. Leighton in Leighton, Lich. Brit. Exs. 401 (BM - neotype; H, UPS - isoneotypes). Neotypification by Ahti (1993: 78).
Chemistry: Subspecies furcata:
Note: Whereas Wirth (1995: 308), Paus (1997), and Scholz (2000: 74) accept two subspecies of Cladonia furcata with or without atranorin, Des Abbayes (1937) and Schade (1966) regard them as extreme ecotypes on silicious and calcicous soil. Günzl (2003: 192) concludes based on molecular investigations of xx samples from northern Germany that there is no reason for accepting subdivisions. Wirth et al. (2011: 34) do not follow these molecular data but continue to use a subsp. furcata and a subsp. subrangiformis (Sandst.) Abbayes. In the German Flora (Wirth et al. 2013: 410) the taxon is accepted as Cladonia subrangiformis L. Scriba ex Sandst.
Chemical race I: Fumarprotocetraric acid, sometimes atranorin, protocetraric acid and additional unidentified substances in traces. Cph-1, Cph-2 see C. Culberson 1969: 312, 1970: 247). Without rangiformic acid, very rarely with atranorin (Wirth 1995: 308). Fumarprotocetraric acid, some with atranorin and physodalic acid (Etayo & Burgaz 1997: 723).
Chemical race II: Additional Psoromic acid in Portugal (Barendregt et al. 1982).
Subspecies subrangiformis (Sandst.) Abbayes:
K+ to K-, atranorin, fumarprotocetraric acid, + bourgeanic acid (Wirth 1995: 308).