1. PLANKTON
Holoplankton:
picoplankton- <2 um - bacteria, prochlorophytes, cyanobacteria
nanoplankton um- diatoms, cocc., silic.
microplankton um - diat., dinoflagellates
Golden-brown algal line- Diatoms (Class Bacillariophyta)- Arctic, Antarctic, temperate and boreal, silica cell wall - frustule composed of hypotheca and epitheca

2. Shapes: centric - radially symmetrical
pennate - bilaterally symmetrical
diatomaceous ooze >30-40% of total sediment composition
binary cell division
sexual reproduction does occur
gametogenesis - resulting zygote usually enlarges to form a large cell - auxospore
doubling/day (Eppley, 1972)

3. Dinoflagellates (Class Dinophyta)
biflagellated –
subtropics
Ceratium, Peridinium - binary fission - sexual reproduction rare
Pfisteria blooms in N.C.– Diane Burkholder

4. “Red Tide”:
Gonylaux & Gymnodinium
toxins - paralytic shellfish poisoning
saxitoxin - accumulates in hepatopancreas of mollusks
interferes with Na transport - depresses synaptic function - within 12 hrs. of ingestion of bivalves human respiration is inhibited and cardiac arrest ensues

5. Red Tides - associated with sudden influxes of nutrients, upwelling, turbulence, land-derived
Bioluminescence - Noctiluca
luciferin – luciferase reaction
endogenous circadian rhythm - max. at night
(Classes Haptophyta and Chrysophyta, Cryptophyta, Eustigmatophyta, Xanthophyta) – Chrysophyta – Chrysophyceae and Rapidophyceae; Haptophyta – Prymnesiophyceae (Coccolithophores) Cryptophyta - Cryptophyceae
spherical CaCO3 coccoliths; Phaeocysts - cold waters - produces poisonous acrylic acid (Guillard, 1971)

6. Trichodesmium (Oscillatoria - nutrient-poor ocean gyres
Blue-green - Class Cyanophyceae - prokaryotes
Trichodesmium (Oscillatoria - nutrient-poor ocean gyres
Prochlorophytes (Prochlorophyceae) - may be important for food
chlorophyll b
Green Algal Line
(Chlorophyta and Euglenophyta) – includes Prasinophyceae (flagellated) and Chlorophyceae-

7. Zooplankton:
Arthropoda – Crustacea (Copepods) - largest group of crustaceans
<1 nm to several mm
calanoid forms dominante
Calanus spp.
Particles trapped on maxillary setules - Acartia tonsa

8. Euphausids – shrimp-like planktonic organisms, 2-5 cm length
Calanus female may lay a 50-egg clutch (depending on food)
interval of days
An equatorial deepening of depth distribution is known as tropical submergence - cold-adapted spp.
Euphausids – shrimp-like planktonic organisms, 2-5 cm length
Antarctic, red color (Astaxanthin)
Euphausia superba - feeds on diatoms

9. Other crustaceans – ostracods, cumaceans, mysids, some amphipods
Cladocera – dominant in freshwater, only important in estuaries - Podon spp. - preys on other zooplankton
Other crustaceans – ostracods, cumaceans, mysids, some amphipods
Protists
Foraminifera - CaCO3 tests - pseudopodia
usually <1 mm, spherical and spinose
high latitudes - rounded (Globigerina)
low latitudes – spinose , Globigerina ooze

10. threadlike pseudopods - axopods
Radiolaria - <50 um to a few mm
silica skeleton
threadlike pseudopods - axopods
some have symbiotic algae - zooxanthellae
asexual reproduction by binary fission
Radiolarian ooze

11. Mnemiopsis - larvae - eats zooplankton- failure of oyster larvae
Ctenophora - transparent, egg-shaped, 8 external rows of meridional plates, exclusively carnivorous
Pleurobrachaia
Mnemiopsis - larvae - eats zooplankton- failure of oyster larvae
gametes shed into water - newly formed embryo is a free-swimming larvae
SO4 - ions lost to enhance specific gravity

12. Arrow worms (Sagitta) - torpedo shaped 4-10 cm in length
Chaetognatha – chaetognaths normally shallow, but may occur in the deep waters
Arrow worms (Sagitta) - torpedo shaped
4-10 cm in length
feed on copepods
hermaphroditic
eggs in water or attached
Annelida (Polychaeta) Tomopteris –paarpodia well-developed

13. Scyphozoa - true jellies (Aurelia aurelia) , feed on zooplankton
Coelenterata - Cnidaria
Scyphozoa - true jellies (Aurelia aurelia)
, feed on zooplankton
Siphonophores - floating hydrozoan colonies, nematocysts may be very large (Physalia, Velella)
Mollusca- (Gastropoda) pteropods – parapodia, thecosomes - sink to bottom
Pteropod ooze

14. Salpa – solitary and Pyrosoma - colonial
Subphylum- Urcochordata – Thaliacea (Salps) tunicates– and Larvacea
Salpa – solitary and Pyrosoma - colonial
feed on phytoplankton, fish larvae – using ciliary mucous net