MARINE ALGAE OF ST . MARTIN ’ S ISLAND , BANGLADESH . IX . NEW RECORDS OF GREEN ALGAE ( CHLOROPHYCEAE )

Cladophora crispula Vickers, Cladophora prolifera (Roth) Kütz. and Phyllodictyon anastomosans (Harv.) Kraft et Wynne are recorded and described for the first time from the St. Martin’s Island, Cox's Bazar, Bangladesh.


Introduction
So far 45 taxa under 17 genera of green algae have been reported from Bangladesh coasts (Islam, 1964(Islam, , 1965(Islam, , 1973(Islam, , 1976;;Islam and Khair, 1978;Salam and Khan, 1980;Islam and Irfanullah, 2000;Aziz et al., 2008).The authors on examination of some preserved samples came across some green algae, which were not recorded earlier from the Bangladesh territory.These are described and illustrated in the present account.

Materials and Methods
Several marine algae collected from the littoral (exposed and knee-deep water below low tide mark) zone of St. Martin's Island, Cox's Bazar district Bangladesh on different occasions were preserved with 4% formalin in marine water.Cladophora prolifera (Roth) Kütz.was collected by Prof. Abdul Aziz, while Cladophora crispula Vickers and Phyllodictyon anastomosans (Harv.)Kraft et Wynne were collected by Dr. Abdullah Harun Chowdhury.

Taxonomic enumeration
Cladophora prolifera and Phyllodictyon anastomosans were found to be growing on exposed rocks, shells and stones while Cladophora crispula was found as an epiphyte on Phyllodictyon anastomosans collected from the coast of St. Martin's Island, Bangladesh.These taxa are new records for Bangladesh and are described and illustrated below.
1. Cladophora crispula Vickers (Fig. 2 A-D) (Taylor 1960, 85;Rios 1972, 227, 2: 8) Plants filamentous, moderately branched, 3.00 mm high; thallus appears to be young, branching mainly monopodial; cells cylindrical, thallus attached by short finger-like rhizoidal extensions from the lower most cell; gradually broadened at the tip, slightly incurved, 248-362 µm long, diameter of broader region varies from 63.50 to 77.55 µm and narrower region from 45.72 to 51.00 µm; tip cells 33.00-50.80µm broad with rounded apex; cell wall thick stratified, chloroplasts reticulate, with many small rounded to ovoid pyrenoides; reproductive structures not observed.Note: Islam (1976) reported Cladophora echinus (Biasoletto) Kütz.& C. patentiramea (Montag.)Kütz.from St. Martin's Island, Bangladesh.The present material does not resemble with any of the above species.The present material resembles to a certain extent with C. gracilis (Griffiths) Kütz.by its branching pattern and cell shape but differs enormously by the size of the plant.The present material is very small (2.5-3.0 mm long) compared to 30 cm for C. gracilis.However, the present material appears to be in early growing stage.
There are 1055 species names in the species database of Cladophora at present, of which 176 are flagged as currently accepted taxonomically.The two species recorded here are among the accepted ones.
Note: Present material differs from other marine species of Cladophora chiefly by predominant opposite branching and rhizoidal extension from cell base.This species differs from C. aokii Yamada by less rhizoidal investment on the main axes.Islam and Hossain (1978) reported Cladophora prolifera from a freshwater body of Dhaka city, about 1 cm high where cells in the middle part of the thallus are typically Cladophoralike, while cells in the apical part are globose to irregular shaped (probably zoosporangia).The size of the plant and variations in cell shape described by Islam and Hossain (1978) do not fit with the present material collected from lower intertidal zone and that of the illustrations and descriptions for species from marine habitat (Newton, 1931;Taylor, 1957Taylor, , 1960)).Thus, it appears that the material described by Islam and Hossain is wrongly identified (that needs to be amended), and by mistake the species has been quoted as marine in Ahmed et al. (2008).Thus, C. prolifera described here is a new record for Bangladesh.
Habitat and local distribution: Plants commonly grow on rocks and stones; Abdul Aziz, 01 March, 1995; AA 9.
Geographical distribution: Cosmopolitan in temperate and tropical zones occurring in brackish and marine conditions (Taylor, 1960).Harv., Struvea anastomosans (Harv.)Picc., S. delicatula Kütz., (?) S. tenuis Zonard.](Fig. 3 A-E) (Nizamuddin 1969, 239;Taylor 1960, 122, 9: 2, 5: 1 as Struvea anastomosans (Harv.)Picc.)Plant densely entangled, filamentous, up to 1.0 cm tall, tufted distally; branching opposite, the main filamentous axes up to 372 µm wide, unsegmented with constrict here and there (6.50-16.00mm) in the lower part of the stalk but segmented above, bearing in a plane 4-6 pairs of opposite branchlet filaments which divide and redivide with decreasing regularity to form the net-work; in older filament cells are 1.6-4.5 mm long and 0.5 mm broad, in young filament cells are 200-400 µm long and 100-172 µm broad; young tip cells very curved 214-365 µm (outer face) and 175-285 µm (inner face) long.Cells are narrowest at the base and the diameter remains more or less same throughout most of its length and then swollen into a knee like structure at the tip, cell tip rounded.In the main filament, the lumen is narrowed to about 26 µm, in most part of the cell while in the most swollen part it is about 166 µm broad; cell wall 25-30 layered; chloroplast reticulate; abundant growth of germlings found on the surface of old filament; reproductive structures were not observed.

Fig. 1 A
Fig. 1 A-D.Cladophora crispula Vickers. A. terminal part of a plant showing predominant unilateral branching; B. An enlarged portion of the plant; C. Apex of a terminal cell showing cell wall and chloroplast structures; D. Stratification of the cell wall and reticulate chloroplast in a median cell.Scales: A, B = 100 µm; C, D = 25 µm.

Fig. 3 A
Fig. 3 A-E.Phyllodictyon anastomosans (Harv.)Kraft et Wynne.A. Basal portion of a plant.B. Enlarged part of the base showing constrictions in the axis and rhizoidal branches.C. Upper part of a plant with branches and branchlets.D. Apex of a developing branch.E. Part of a mature branch.Scales: A, C = 1 cm; B = 500 µm; D, E = 200 µm.