Prorocentrum sculptile Faust, 1994
Species Overview:
Prorocentrum sculptile is an armoured, marine, sand-dwelling, benthic dinoflagellate species. This species is associated with colored sand and coral rubble in tropical embayments of the Caribbean Sea.
Taxonomic Description:
Prorocentrum sculptile is a bivalvate species often observed in valve view. Cells are broadly ovate, 32-37 µm long and 30-32 µm wide, with an angled and deeply indented anterior end (Figs. 1,5). Both valves are concave in the center (Figs. 1,5). The intercalary band is smooth (Figs. 1-3) (Faust, 1994).
The valve surface is marked with evenly distributed, round to oblong shallow depressions (Figs. 1-6). The depression margins are smooth with an average diameter of 0.4 µm (Fig. 4). Approximately 856-975 shallow depressions per valve. Some depressions contain trichocyst pores: small round openings 0.13 µm in diameter. Trichocysts and trichocyst pores can be seen only at high magnification of well-preserved specimens (Figs. 4-6) (Faust, 1994).
The periflagellar area on the right valve is a deep and narrow, V-shaped, distally angled depression, 7-8 µm long. This region houses a large, thin, inclined periflagellar plate (1.5 X 5 µm) (Fig. 5). The left valve is excavated and curved along the apical margin (Fig. 2) (Faust, 1994).
Morphology and Structure:
Cells of the sand-dwelling species P. sculptile are deep brown in color, are photosynthetic with golden brown chloroplasts, and have a centrally located pyrenoid and a large posterior nucleus (Faust, 1994).
Reproduction:
Prorocentrum sculptile reproduces asexually by binary fission.
Species Comparison:
Only two Prorocentrum species are known with a periflagellar area that is a deep and narrow V-shaped, distally curved depression: P. sculptile and P. emarginatum (Faust, 1990b). These species differ in a number of characteristics: a.) P. sculptile has a thin, inclined periflagellar plate, whereas P. emarginatum has a rigid, rectangular periflagellar plate (Faust, 1990b); b. ) the valve surface of P. sculptile is covered with round to oval shallow depressions, whereas the valve surface of P. emarginatum is covered with round smooth-edged pores arranged radial rows (Faust, 1990b); c.) P. sculptile is a smaller species (30-37 µm) than P. emarginatum (35-40 µm) (Fukuyo, 1981, Faust, 1990b); d.) the intercalary band is smooth in P. sculptile but transversely striated and sinuous in P. emarginatum (Faust, 1990b); and e.) P. sculptile has a pyrenoid, whereas P. emarginatum (Faust, 1990b) does not.