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Attitash 20160908 (Amesbury, MA)

Anabaena spp.

Three 'species' or strains with different cell size and shape. Horizontal filament in lower image has a hyaline sheath, unusual in the genus, as well as an akinete (spore) on another trichome - the larger greener cell.

Aphanocapsa sp.

Ceratium hirundinella exploded under cover slip

Cyclotella cf. comta or meneghiniana valve

Euglena sp.

Isthmochloron sp. (Tribophyceae)
Easily mistaken for a desmid (cf. Staurastrum)

Lyngbya cf. pusilla, the narrowest filament in this genus
Compare to Schizothrix - has a wider sheath and is benthic

Mallomonas sp.

Melosira sp. showing (A) vegetative trichome (filament lacking sheath); (B) developing auxospore; (C) mature auxospore with >2x diameter of vegetative cells.

Microcystis cf. aeruginosa
Two polymorphs with differing viscosity of mucopolysaccharide sheath - more watery on left and more viscous on right image.  Komárek separated the more viscous form as Diploneis wesenbergii (1958), then moved it to M. wesenbergii, which Joosten claims is invalic (Joosten 2006).  A preferable name is M. aeruginosa forma wesenbergii.  Seasonal and other environmental variables apparently affect growth forms that are likely variant expressions of the same genotype.

Joosten, A.M.T. (2006). Flora of the blue-green algae of the Netherlands I The non-filamentous species of inland waters. pp. [1-]5-237. Utrecht: KNNV Publishing.

Trachelomonas spp.
Upper images - same cell, different focal planes
Lower image - T. cf. bomba
Stain on lorica (shell) is likely iron oxides that mask chlorophyll green.

Woronochinia sp.
One should keep in mind the gradient in colony morphotypes within Microcystis and question whether this is a valid genus.

Oscillatoria cf. redekii
Relatively colorless cells with gas vessicles located at both ends of cells.

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