Abstract:
Thirty-six species of epilithic brown algae, with multicellular, foliaceous and
thalloid organizations belonging to three classes, three orders, four families and
fifteen genera of the phylum Phaeophycota have been collected from Manora,
Hawkesbay, Buleji and Paradise Point, the coastal areas near Karachi (Pakistan)
during March 2006 and June 2010. They were morphologically investigated,
identified with the help of existing literature and taxonomically described. As a result
of that three new species viz. Iyengaria nizamuddinii, Spatoglossum shameelii and S.
qaiserabbasii were discovered and eleven species were described for the first time
from the coast of Pakistan. The occurrence of Padinopsis is its first record of growth
in the Indian Ocean. In the previously described species, several new characters and
taxonomic variations were recorded.
Later on the collected species were investigated anatomically in detail. For this
purpose, the thalli were first studied in surface view. Then cross sections (CS) were
obtained from apical middle and lower parts of the thalli and microscopically
examined to understand mode of growth and morphogenesis of thallus. Wherever
possible, the CS and longitudinal sections (LS) of stipe, holdfast or heptron were
obtained, in several cases the marginal portion of the thalli were also studied. The
anatomy of fertile parts was investigated to understand reproductive structures, their
development and pre-fertilization changes. The information obtained was compared
with the previously published descriptions and discussed in each species. In most of
the cases new and much detailed information was obtained and several new
anatomical features were discovered.