Photo from © www.micrographia.com Photo from © www.micrographia.com

SCENEDESMUS SPIROGYRA

World Register of Marine Species National Park Service

PARALIA ASTERIONELLA

Photo from © www.micrographia.com

ANABAENA CERATIUM

PHYTOPLANKTON of the HUDSON RIVER ESTUARY SPIROGYRA SCENEDESMUS

What is it? one of many species of green What is it? one of many species of green algae in the genus Spirogyra algae in the genus Scenedesmus How big is it? microscopic cells join end-to- How big is it? microscopic cells (about .02 end to form strings mm across) form groups in multiples of two What eats it? eaten by zooplankton, tiny What eats it? eaten by zooplankton, tiny invertebrates, some small fish invertebrates, some small fish Where does it live? a variety of species Where does it live? a variety of species live in in fresh water; rivers, ponds, lakes, & live in fresh water; rivers, ponds, lakes, & marshes marshes What is its life cycle? reproduces by cell What is its life cycle? reproduces by cell division division

ASTERIONELLA PARALIA

What is it? Asterionella formosa is a What is it? Paralia sulcata (formerly (once called yellow-) Melosira sulcata) is a diatom (once called How big is it? individual cells are yellow-brown algae) microscopic (.07 mm); they attach together How big is it? individual cells are in star-like groupings microscopic (.02 mm across); they attach What eats it? eaten by zooplankton, tiny together end-to-end invertebrates, some small fish What eats it? eaten by zooplankton, tiny Where does it live? fresh & brackish water invertebrates, some small fish in the Hudson Where does it live? brackish & salt water What is its life cycle? reproduces by cell What is its life cycle? reproduces by cell division division

CERATIUM ANABAENA What is it? Ceratium hirundinella is a What is it? one of many species of dinoflagellate cyanobacteria (formerly called blue-green How big is it? microscopic cells about .05 mm algae) in the genus Anabaena long How big is it? microscopic cells (about .01 mm What eats it? eaten by zooplankton, tiny across) join end-to-end to form strings invertebrates, some small fish; can What eats it? eaten by zooplankton, tiny photosynthesize but also consumes algae, invertebrates but produces poisons that can bacteria, & other dinoflagellates cause illness & death in wildlife Where does it live? one of the few Ceratium Where does it live? mostly fresh & brackish species that lives in fresh water water in the Hudson What is its life cycle? reproduces by cell What is its life cycle? reproduces by cell division division

PHYTOPLANKTON of the HUDSON RIVER ESTUARY