Pterosiphonieae

Black tassel Pterosiphonia bipinnata, from Seaweeds of Alaska.

Belongs within: Rhodomelaceae.

The Pterosiphonieae is group of Rhodomelaceae exhibiting bilateral apical development but no primary dorsiventrality (Womersley 2003).

Characters Thallus erect (often with a prostrate base) or largely prostrate, branching bilateral with discrete, alternate, terete to compressed, distichous laterals, or flat and elongate with short marginal determinate laterals, or branched with foliose rounded apices. Branches one cell thick with a small-celled cortex, or 2 cells thick and ecorticate, with or without a midrib. Structure. Apical cells dividing transversely to form axial cells, with the subapical cells dividing obliquely to form alternate distichous laterals. Frond apices with a single apical cell or a margin of several to numerous apical cells, each forming polysiphonous systems congenitally fused at their base to the axis, or fused along their whole length to form flat fronds; pericentral cells 4 to numerous, in some genera transversely divided. Trichoblasts rare and associated only with sexual reproduction, or frequent on the thallus surface or margin. Cells generally uninucleate. Reproduction: Gametophytes usually dioecious. Procarps with a 4-celled carpogonial branch and sterile cells, surrounded by a pericarp prior to fertilization; carposporophyte with a basal fusion cell and branched gonimoblast with terminal carposporangia. Cystocarps usually ovoid, pericarp ecorticate or lightly corticate. Spermatangial organs replacing trichoblasts or branches thereof. Tetrasporangia in terete lateral branches or in stichidia associated with trichoblast tufts on the thallus margin or surface, spirally arranged and single per segment.

Pterosiphonieae
    |--Symphyocladia Falkenberg in Schmitz & Falkenberg 1897 W03
    |    `--*S. marchantioides (Harvey) Falkenberg in Schmitz & Falkenberg 1897 (see below for synonymy) W03
    |--Heterostroma Kraft & Wynne 1992 W03
    |    `--*H. nereidiis Kraft & Wynne 1992 W03
    |--Pollexfenia Harvey 1844 [incl. Jeannerettia Hooker & Harvey in Harvey 1847] W03
    |    |--*P. pedicellata Harvey 1844 (see below for synonymy) W03
    |    |--P. crispata (Zanardini) Falkenberg in Schmitz & Falkenberg 1897 (see below for synonymy) W03
    |    `--P. lobata (Hooker & Harvey) Falkenberg 1901 (see below for synonymy) W03
    |--Dictyomenia Greville 1830 W03
    |    |--*D. tridens (Mertens) Greville 1830 (see below for synonymy) W03
    |    |--D. angusta Agardh 1897 W03
    |    |--D. harveyana Sonder 1853 (see below for synonymy) W03
    |    `--D. sonderi Harvey 1858 [incl. D. sonderiana Agardh 1897] W03
    `--Pterosiphonia Falkenberg in Schmitz & Falkenberg 1897 W03
         |--*P. cloiophylla (Agardh) Falkenberg in Schmitz & Falkenberg 1897 W03 [=Polysiphonia cloiophylla L27]
         |    |--P. c. var. cloiophylla L27
         |    `--P. c. var. corymbosa Kützing 1849 L27
         |--P. arctica Setchell & Gardner 1903 S57
         |--P. bipinnata (Postels & Ruprecht) Falkenberg 1901 [=Polysiphonia bipinnata] S57
         |    |--P. b. var. bipinnata S57
         |    `--P. b. var. robusta (Gardner) Doty 1947 S57
         |--P. dendroidea (Montagne) Falkenberg 1901 [=Polysiphonia dendroidea] S57
         |--P. gracilis Kylin 1925 S57
         |--P. pennata (Agardh) Sauvageau 1897 (see below for synonymy) W03
         `--P. simplicifilum (Agardh) Laing 1927 [=Polysiphonia simplicifilum] L27

Dictyomenia harveyana Sonder 1853 [incl. D. harveyana var. flabelligera Harvey 1863, D. interstincta Agardh 1885, D. spinulosa Kützing 1864] W03

*Dictyomenia tridens (Mertens) Greville 1830 [=Fucus tridens Mertens ex Turner 1819, Rhodomela tridens (Mertens) Agardh 1822] W03

Pollexfenia crispata (Zanardini) Falkenberg in Schmitz & Falkenberg 1897 [=Melanoseris crispata Zanardini 1874, Jeannerettia crispata (Zanardini) Papenfuss 1942; incl. Pollexfenia ciliaris Agardh in Tate 1882 (n. n.)] W03

Pollexfenia lobata (Hooker & Harvey) Falkenberg 1901 [=Jeannerettia lobata Hooker & Harvey in Harvey 1847, Botryoglossum lobatum (Hooker & Harvey) Kützing 1849; incl. J. frondosa Harvey 1855, J. latifolia Kützing 1866] W03

*Pollexfenia pedicellata Harvey 1844 [=Jeannerettia pedicellata (Harvey) Papenfuss 1942; incl. P. crenata Agardh 1892, J. crenata (Agardh) Papenfuss 1942, P. nana Agardh 1892, J. nana (Agardh) Papenfuss 1942] W03

Pterosiphonia pennata (Agardh) Sauvageau 1897 [=Hutchinsia pennata Agardh 1824, Polysiphonia pennata (Agardh) Agardh 1842] W03

*Symphyocladia marchantioides (Harvey) Falkenberg in Schmitz & Falkenberg 1897 [=Amansia marchantioides Harvey 1855] W03

*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.

[W03] Womersley, H. B. S. 2003. The Marine Benthic Flora of southern Australia. Rhodophyta pt IIID. Ceramiales—Delesseriaceae, Sarcomeniaceae, Rhodomelaceae. Flora of Australia Supplementary Series 18. Australian Biological Resources Study: Canberra, and the State Herbarium of South Australia: Adelaide.