Page 103 - e-Book

Keywords: Marine macroalgae (Seaweeds), Floristic survey, Northern Coastal districts,

Distributional additions and Andhra Pradesh.
INTRODUCTION

Marine flora is taxonomically very diverse and falls into mangroves, seagrasses,
microalgae and marine macroalgae (seaweeds). Among them, marine macroalgae are the

grounding group to play a vital role in the regulation of the oceanic environment. They are
exclusively found in marine habitats and rarely able to withstand in other unusable

environments. The organization of the plant body of marine macroalgae is differentiated into

holdfast, stipe and frond, which range from unicellular organisms to nonvascular filamentous
or thalloid plants (Lightowler & Davies, 2002). Characteristically, they are epilithic and grow

on a solid substrate such as rocks, bedrocks, pebbles, mollusc shells and corals in shallow,

intertidal, subtidal zones and deep waters of the sea, even up to a depth of 150 m (Markager
& Jensen, 1994).

Marine macroalgae are broadly classified into three classes viz. Chlorophyceae (Green),
Phaeophyceae (Brown) and Rhodophyceae (Red), based on the nature of colour, reserve food

materials, cell wall and type of photosynthetic pigments (Myslabodski, 2001). The diversity
of seaweeds enormous in tropical regions than the temperate regions due to the incidence on

hydrological and ecological parameters (Silva, 1992). They constitute about 11,000 taxa

which include Rhodophyceae with 7,200 species, followed by Phaeophyceae with 2,000 taxa
and Chlorophyceae with 1,800 taxa (http://www.seaweed.ie/). Whilst, a total of 865 taxa of

seaweeds, belonging to 234 genera have been reported so far from India (Rao & Gupta,
2015).

In India, several periodical studies have been conducted for the exploration of marine
macroalgae from the maritime states. The distribution and diversity of seaweeds always

greater on the west coast than on the east coast. Tamil Nadu coast shows the maximum

number of seaweeds with 426 species (Anon., 1978), trailed by Maharashtra coast with 240
species (Sonali, 2010); Gujarat coast with 198 species (Jha et al., 2009); Lakshadweep

islands with 82 species (Anon., 1979) and Andaman & Nicobar islands with 80 species

(Muthuvelan et al., 2001); Karnataka with 78 species (Kaladharan & et al., 2011); Diu island
with 70 species (Mantri & Subba Rao, 2005); Andhra Pradesh with 80 species

(Umamaheswararao & Sreeramulu, 1970); West Bengal with 14 species (Mukhopadhyay &
Pal, 2002); Odisha with 14 species (Sahoo et al., 2003).

The evidence on the occurrence and distribution of seaweeds in the east coast especially
of Andhra Pradesh is limited and poorly swotted by a few of the researchers. Sreeramulu

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