Callithamnion

Callithamnion pikeanum, copyright Gary W. Saunders.

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 1925 S57
    |--C. biseriatum Kylin 1925 S57
    |--C. bisporum Gardner 1927 S57
    |--C. colensoi Hooker & Harvey 1855 L27
    |--C. consanguineum Hooker & Harvey 1855 L27
    |--C. cryptopterum (Hooker & Harvey) Kützing 1849 [incl. C. micropterum Hooker & Harvey 1847 (preoc.)] L27
    |--C. gracile Hooker & Harvey 1847 L27
    |--C. laxum Setchell & Gardner in Gardner 1927 [=Ceratothamnion pikeanum f. laxum] S57
    |--C. pikeanum Harvey 1853 [=Ceratothamnion pikeanum] S57
    |    |--C. p. var. pikeanum S57
    |    `--C. p. var. pacificum (Harvey) Setchell & Gardner in Gardner 1927 [=C. arbuscula var. pacifica] S57
    `--C. puniceum Hooker & Harvey 1855 L27

*Type species of generic name indicated

REFERENCES

[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.