Nitzschia (Nitzschia sp. (large)) is prey of:
Argia vivida
Enallagma anna
Ophiogomphus severus
Baetis tricaudatus
Hyalella azteca
Hydropsyche occidentalis
Simulium argus
Tricorythodes minutes
Aphrophila noevaezelandiae
Austrosimulium australense
Naonella
Tanytarsini
Coloburiscus humeralis
Helicopsyche albescens
Hydora nitida
Oligochaeta I
Oligochaeta II
Pycnocentrodes evecta
Zealolessica cheira
Amphipoda
Orthocladiinae
Maoridiamesea
Eukiefferiella
Podonomus
Polypedellum
Deleatidium
Oligochaeta type weak-long-short
Oxyethira albiceps
Potamopyrgus antipodarum
Scirtidae
Aoteapsyche
Austroclima jollyae
Ceratopogonidae
Cricotopus II
Stictocladius
Hudsonema amabilis
Nesameletus ornatus
Oniscigaster
Orchymontia
Paranephrops zealandicus
Podaena
Potamopurgus antipodarum
Stratiomyidae
Baraeoptera roria
Diamesid Blond
Eriopterini
Hydraena homolaena
Olinga feredayi
Pycnocentrodes
Eukiefferiella Shiny Black
Orthoclad Blue Black
Orthoclad Blue Blond
Chironomid type Polyped
Chironomid type Slant-eye
Corynoneura
Tanytarsini II
Hydrobiosella stenocerca
Orychmontia
Pycnocentria
Tanyderidae
Zelandoperla
Zephlebia spectabilis
Pirara
Cricotopus I
Tabanidae
Austraclima jollyae
Tanytarsini I
Hexatomini
Hydraena homalaena
Hydrobiosella
Paroxyethira eatoni/hintoni
Zelandoperlinae
Acroperla
Austroperla cyrene
Olinga feredayii

Based on studies in:
USA: Idaho-Utah, Deep Creek (River)
New Zealand: Otago, Blackrock, Lee catchment (River)
New Zealand: Otago, Broad, Lee catchment (River)
New Zealand: South Island, Canton Creek, Taieri River, Lee catchment (River)
New Zealand: Otago, Dempster's Stream, Taieri River, 3 O'Clock catchment (River)
New Zealand: Otago, Healy Stream, Taieri River, Kye Burn catchment (River)
New Zealand: Otago, Kye Burn (River)
New Zealand: Otago, Little Kye, Kye Burn catchment (River)
New Zealand: Otago, Stony, Sutton catchment (River)
New Zealand: Otago, Sutton Stream, Taieri River, Sutton catchment (River)
New Zealand: Otago, German, Kye Burn catchment (River)

This list may not be complete but is based on published studies.