Halimeda distorta   (Yamada) L.H. Colinvaux  (Algae)
Organism information awaits expert curation
Taxonomy
Kingdom:Plantae
Phylum:Chlorophyta
Class: Bryopsidophyceae
Order:Bryopsidales
Family:Halimedaceae

Image copyrights: Bishop museum

Description
Size: Height 14 cm

The alga presents a very bushy appearance because of the close polychotomous mode of branching, branches originating almost from every successive segment. Generally the lower nodes of the thallus are more conspicuous than the upper ones. The segments are ribbed and very small, 0.5-1.0 cm in diameter and 0.4-0.7 cm in height and 1 mm in thickness. The segments being heavily calcified, are brittle. They are auriculate in outline with undulate margins or sometimes slightly lobed. The segments are characteristically distorted. The rhizoids arise from the lateral margin of the lower segments. They have contact with the substratum at more than one locus. Some of the lower branches of the thallus creep on the substratum, helping in anchorage.

There is a central medulla surrounded by a cortex. The medulla comprises of numerous vertically running medullary filaments, hence the thallus is multiaxial in construction. The medullary filaments are 44 µm to 59.4 µm broad, branching trichotomously. The cortex is made up of three zones of utricles unlike in many other species, the utricles are just made up of dichotomies which do not undergo ant structural modifications. The cortical filament decreases in diameter from the centre towards the periphery. The submarginal utricle usually bears four peripheral utricles. In surface view the peripheral utricles are hexagonal in appearence and measure 13.22 µm to 39.6 µm in diameter. At the nodal regions, the medullary filaments fuse in pairs for a short distance (twice their diameter). This type of fusion is usually called a "short fusion". Calcium carbonate is deposited in the form of orthorhombic aragonite crystals which occur individually as well as in aggregates. The crystals measure 26.4 µm to 184.8 µm in length and 6.6 µm to 39.6 µm in thickness.

Cluster of gametangia are borne on a branched gametophore.


Synonym (s)
Halimeda incrassata f. distorta Yamada, 1941

Common Name (s)
Economic Importance and Threats

Ecology
Habitat:  Coastal

Biogeography


• Tamil Nadu, Pamban (Lat: 9.29) (Long: 79.21) INDIA
• Tamil Nadu, Pamban Coast INDIA (Record: 29/07/1992-01/08/1992)
• Tamil Nadu, Kundugal INDIA (Record: 29/07/1992-01/08/1992)

Literature Source(s)
  • Rao, DVS (2005) Comprehensive review of the records of the biota of the Indian Seas and the introduction of non-indigenous species Aquatic Conservation: Marine and Freshwater Ecosystems John Wiley and Sons, Ltd. 15(2) 117-146 Available at - http://dx.doi.org/10.1002/aqc.659
  • (2006) Algaebase Available at - http://www.algaebase.org/
  • Oza, RM and Zaidi, SH (2001) A revised checklist of Indian marine algae Available at - NIO, Goa
  • Cook Islands biodiversity and natural heritage Available at - http://cookislands.bishopmuseum.org/
  • Society for the Management of European Biodiversity Data (2009) World Register of Marine Species (WoRMS) Available at - http://www.marinespecies.org
  • Sundararajan, M; Selvaraju, C and Krishnamurthy, V (1996) On some species of Halimeda Lamour from Indian waters Seaweed Research and Utilisation Seaweed Research and Utilisation Association 18(1-2) 21-33 Available at - NIO, Goa

Page last updated on:2010-10-22

Back to Search