At the other are tiny transparent tunicates called larvaceans
, most no bigger than a grain of rice, which can be so abundant they turn the water to a murky goop.
Overall, the estuary midstream and upstream supported the highest densities of protozoans, rotifers, and most meroplanktonic larvae, whereas the estuary downstream supported the highest densities of copepods, cladocerans, ostracods, molluscs, chaetognths, and larvaceans
and their houses as important food for some pelagic copepods.
Production of tropical larvaceans
in Kingston Harbour, Jamaica: are we ignoring an important secondary producer?
Such fine resolution enables detection of particles as small as a 100 [micro]m (e.g., diatoms), although the ability to clearly resolve particles is typically in the range of 700 [micro]m (i.e., small copepods and larvaceans
) and larger sizes (e.g., larval fishes, chaetognaths, and ctenophores).
Many groups of organisms including cnidarians, ctenophores, radiolarians, shrimp, ostracods, squid, chaetognaths, ophiuroids, larvaceans
, and deep-sea fishes produce light by oxidizing coelenterazine, although each organism makes its own luciferase to catalyze the reaction (Shimomura, 2006; Haddock et al., 2010).
1 Urochordata [Ascidians (Tunicates or Sea Squirts), Larvaceans
(Appendicularians), Thaliaceans (Salps, Doliolids, and Chain Tunicates)]
Miscellaneous prey items included other fish, larvaceans
, mysids, shrimp, and other prey (Fig.
Amphipods and larvaceans
(collected at all times), were fourth and fifth in abundance respectively.
Resembling jellyfish, larvaceans
are finger-shaped creatures that spin fragile webs of mucus around themselves.
, and pteropods (Thecosomata) each occurred in >20% of the stomachs and had mean individual prey weights <0.8 mg.
Pseudothecosomatous pteropods use mucous webs manipulated by ciliary action to feed in the midwater (Gilmer, 1972), and larvaceans
produce elaborate mucous feeding structures.