Callithamnion

Belongs within: Ceramiales.

Callithamnion is a genus of irregularly branched red algae.

Characters (from Scagel 1957): Thallus a branched monosiphonous filament, with branching predominately irregular; axis obscure to percurrent with major branches sometimes uncorticated or sometimes corticated nearly to apex; sporangia with four tetraspores.

<==Callithamnion
    |--C. acutum Kylin 1925S57
    |--C. arbusculaG64
    |--C. barbatumG64
    |--C. biseriatum Kylin 1925S57
    |--C. bisporum Gardner 1927S57
    |--C. borreriG64
    |--C. brodieiG64
    |--C. colensoi Hooker & Harvey 1855L27
    |--C. consanguineum Hooker & Harvey 1855L27
    |--C. corymbosumG64
    |--C. cryptopterum (Hooker & Harvey) Kützing 1849 [incl. C. micropterum Hooker & Harvey 1847 (preoc.)]L27
    |--C. daviesiiG64
    |--C. floccosumG64
    |--C. floridulumG64
    |--C. gracile Hooker & Harvey 1847L27
    |--C. gracillimumG64
    |--C. granulatum [incl. C. spongiosum]G64
    |--C. hookeriG64
    |--C. laxum Setchell & Gardner in Gardner 1927 [=Ceratothamnion pikeanum f. laxum]S57
    |--C. mesocarpumG64
    |--C. pikeanum Harvey 1853 [=Ceratothamnion pikeanum]S57
    |    |--C. p. var. pikeanumS57
    |    `--C. p. var. pacificum (Harvey) Setchell & Gardner in Gardner 1927 [=C. arbuscula var. pacifica]S57
    |--C. plumaG64
    |--C. polyspermumG64
    |--C. puniceum Hooker & Harvey 1855L27
    |--C. roseumG64
    |--C. rothiiG64
    |--C. sparsumG64
    |--C. tetragonum [incl. C. brachiatum]G64
    |--C. tetricumG64
    |--C. thuyoidesG64
    |--C. tripinnatumG64
    `--C. virgatulumG64

*Type species of generic name indicated

References

[G64] Gray, J. E. 1864. Handbook of British Water-weeds or Algae. R. Hardwicke: London.

[L27] Laing, R. M. 1927. A reference list of New Zealand marine algae. Transactions and Proceedings of the New Zealand Institute 57: 126–185.

[S57] Scagel, R. F. 1957. An annotated list of the marine algae of British Columbia and northern Washington (including keys to genera). National Museum of Canada Bulletin 150: 1–289.