Sub-division :- Algae

Class :- Rhodophyceae

Sub-class :- Florideae

Order :- Nemalionales

Family :- Batrachospermaceae

Genus :- Batrachospermum

Batrachospermum is commonly found in fresh waters. The filaments are attached to stones in slow moving waters of rivers and streams or on the margins of the lakes.




  • Thallus is multicellular and filamentous. Filaments are branched.
  • Adult thallus appears as a chain of beads. It is mucilaginous and violet or blue in colour.
  • Thallus remains attached to the substratum by old shoots which form a prostrate system.
  • The main axis (primary axis) is corticated. It is differentiated into nodes and internodes. Branches are borne at the nodes.
  • Two types of branches occur-(i) branches of unlimited growth and (ii) branches of limited growth.
  • Primary axis and branches of unlimited growth arise from nodes. These show monopodial or pseudo-dichotomous branching.
  • Long branches or branches of unlimited growth are differentiated into small nodes and long internodes.
  • Primary axes and branches of unlimited growth are enveloped by several layered cortex.
  • Dwarf branches or branches of limited growth arise laterally in whorls from the nodes of primary axes. (Clusters thus formed give beaded appearances to the thallus).
  • Each cluster formed at the node, is called a glomerule.
  • The laterals consist of small, ellipsoidal or moniliform and uninucleate cells.
  • Among these lateral branches are situated large clusters of carpospores.

Batrachospermum. Thallus to show external features.


Reproductive structures of BATRACHOSPERMUM


  • The species are monoecious and male and female sex organs occur near the apex.
  • Male sex organs are antheridia. These are present in clusters on short branches of lateral filaments.
  • Antheridia are oblong or spherical and unicellular.
  • Each antheridium produces a single, spherical, colourless, naked, uninucleate and non-motile spermatium.
  • Female sex organs are carpogonia situated at the apex of 3-4 celled lateral carpogonial branch.
  • Carpogonium is made of a basal swollen portion with a terminal, elongated, tubular process called trichogyne.
  • As a result of fertilization cystocarp is formed. This appears as a cluster of carpospores in glomerules.
  • Cystocarp remains covered by sterile branches.
  • Inside the cystocarp lie many branched gonimoblast filaments.
  • The terminal swollen cells of these filaments are carposporangia. Each carposporangium produces a single carpospore.

Batrachospermum. A part of fertile branch with glomerule and carposporangia.



  • Sub-division– Algae
    1. Presence of a simple thallus.
    2. Chlorophyll present
    3. Cell wall made of cellulose.
  • Class– Rhodophyceae
    1. Chromatophores pure red to dark purple.
    2. Photosynthetic reserve-floridean starch and floridoside.
    3. Male gametes non-motile.
    4. Female reproductive organ with trichogyne-a receptive structure.
    5. Post-ferilization product a cystocarp.
  • Sub-class :- FIorideae
    1. Thallus basically filamentous.
    2. Pit connections between sister cells.
    3. Cells with more than one chromatophore.
    4. Carpogonium highly specialised.
  • Order– Nemalionales
    1. Plants filamentous, corticated, unior multiaxial.
    2. Cells uninucleate, chromatophores axial or lateral.
    3. Cystocarps superficial or deeply embedded in the thallus.
    4. Life cycle without free-living tetrasporophyte.
  • Family – Batrachospermaceae
    1. Inhabit freshwater.
    2. Thallus uniaxial.
    3. Life cycle haplobiontic.
  • Genus – Batrachospermum
    1. Main axis and branches free from one another.
    2. Branching appears beaded.
    3. Threads embedded in large amount of mucilage.







Leave a Reply

Your email address will not be published. Required fields are marked *