Cyclotella (Cyclotella sp.)
Centric diatom. Planktonic (floater)
Kingdom: Plantae; Division Chrysophyta; Class Bacillariophyceae; Order Centrales; Family Coscinodiscaceae. White scale bar is 5 microns

Cells usually solitary, but sometimes united to short chains. Valves circular, strongly to weakly undulate, undulations more evident in the middle area. Middle area punctate, marginal area striate. Valve disc divided into two portions, the exterior annular, with striae smooth (costae) or puntate, more or less fine, sometimes intermixed with small spines; always without a pseudo-nodule; center often bullate, smooth or granular, with rangules sparse or radiating.

Melosira (Melosira sp.)
Centric diatom. Planktonic (floater)
Kingdom: Plantae; Division Chrysophyta; Class Bacillariophyceae; Order Centrales; Family Coscinodiscaceae. White scale bar is 5 microns

Cells closely united to more straight, beadlike chains by the middle of the valve faces. Frustules globose, elliptical or cylindrical. Valves circular, often deeply convex and possessing a deep valve mantle, often with "small teeth" or short spines at the unction of the frustules, which are united into a filament. Valve surface either simple punctate or punctate an areolate, punctate usually in radiating lines or fascicules, often somewhat irregularly scattered in the center.

Surirella (Surirella sp.)
Kingdom: Plantae; Division Chrysophyta; Class Bacillariophyceae; Order Pennales; Family Surirellaceae. White scale bar is 5 microns

Cells solitary, frustules in girdle view cuneate. Valves ovate, cuneate, reniform, elliptical or linear. Asymmetrical on the trans-apical axis, upper end usually broadly rounded, lower end cuneate or sub-acute. Valve surface costate, costae either short, or lengthened so that they meet at a median line in the apical axis. Central space often called the pseudoraphe, linear, lanceolate, often obscure, sometime hyaline or bearing faint folds or striae. Margins of the valve elevated to form wing-like extensions orkeels (algae). Upon the edge of this wing-like extension is borne the raphe, and fine channels or canaliculi running through the substance of the supports of the wings connect the raphe with the internal cell contents. In some species the algae are short and not easily recognized when the cell is lying in valve view, but are more evident when the cell presents the girdle view. In some species the valve surface is finely punctate between the Costa, in others the puncta are arranged in marginal striae, or scattered over the central portion of the valve. some species are spirally twisted about the apical axis, or have ellipitcal outlines symmetrical on the apical and transpical axes, but slightly constricted in the middle, to have a panduriform appearance. Generally a bottom and littoral form, occasionally occurring as plankton. 

Tabellaria (Tabellaria sp.)
Kingdom: Plantae; Division Chrysophyta; Class Bacillariophyceae; Order Pennales; Family Tabellariaceae. White scale bar is 5 microns

Cells quandrangular forming zigzag or straight filaments. Valves linearor oblong, inflated in the middle and at the apices. Rectangular in girdleview. Intercalary bands and septa present. In girdle view, the septa appear as short thickened lines. In valve view the septa extends at varying lengths under the surface of the valves. Valve finely striated, striae transverse, costae absent. Pseduoraphe narrow.

Cymbella (Calidris mauri)
Kingdom: Plantae; Division Chrysophyta; Class Bacillariophyceae; Oder Pennales; Family Cymbellaceae. White scale bar is 5 microns

Valve asymmetrical to the apical axis. Dorsal margin convex, ventral margin more or less straight; convex or concave. Axial area nearer the ventral margin in most species; central area with or without punctae.

Synedra(Synedra sp.)
Kingdom: Plantae; Division Chrysophyta; Class Bacillariophyceae; Oder Pennales; Family Fragillariaceae. White scale bar is 5 microns

Cells free or united into ribbon-like or gan-like clustered star-like colonies. Frustules linear, linear-lanceolate to very narrow lanceolate; apical axis is occupied by the pseudoraphe.Valves surface usually with transpical rows of deliate puncta and narrower pseudoraphe or wide lanceolate, hyaline area sometimes with scattered puncta.Lateral longitudinal ribs may be present in some forms.