Calamites STERNBERG

Cleal, Christopher J. & Thomas, Barry A., 2018, Nomenclatural Status Of The Palaeobotanical “ Artificial Taxa ” Established In Brongniart’S 1822 “ Classification ” Paper, Fossil Imprint 74 (1 - 2), pp. 9-28 : 14

Calamites STERNBERG typ. et orth. cons.

1820 Calamites SCHLOTHEIM , p. 398 (nom. inval.).

1820 Calamitis STERNBERG, p. 24.

1822a Calamites BRONGNIART , p. 209 (orth. cons.).

Ty p e. Calamites suckowii BRONGNIART, 1828b, p. 124 (typ. cons.); Loc.: Middle Pennsylvanian Series, Dudweiler, near Saarbrücken, Germany (see comments in Cleal et al. 2012).

D i a g n o s i s. “Tiges articulées striées régulièrement, impressions arrondies, petites, nombreuses, formant un anneau autour de chaque articulation, ou quelquesfois nulles.”

D i s c u s s i o n. The nomenclatural status of Calamites has been the subject of some confusion and a number of proposals have been made (Lanjou 1953, Anon. 1954, Storch 1981, Greuter et al. 1994, Cleal et al. 2012). The position summarised above is that given in the most recent proposal ( Cleal et al. 2012) and is the basis for its status as a conserved name in the current ICN.

The name is widely used for a fossil-genus of adpressions, casts and pith-casts of stems and rhizomes, mainly from Carboniferous and Permian floras, and usually regarded as belonging to the Sphenophyta (e.g. Jongmans 1911, Crookall 1969). Their anatomy is well documented (e.g. Andrews 1952, Eggert 1962, Rössler and Noll 2006, 2007) and there are three basic structural types that are generically distinguished: Calamitea COTTA, 1832 , Arthropitys GOEPPERT, 1864 , and Arthroxylon REED, 1952 . Since it is impossible to determine which of these anatomies corresponds to the nomenclatural type of Calamites , the latter should only be used for adpressions, casts and pithcasts, and not for anatomically-preserved fossils.