PLANKTONIC CRUSTACEANS
CLADOCERA
Filter feeders (Branchiopoda or
Fillopoda)
Bivalve carapax (head outside)
NO larvae
Parthenogenesis
Reduced segmentation
COPEPODA
Filter feeders and predators
No carapax
Nauplius
Naked abdomen
urosome
OSTRACODA
Filter feeders
Bivalve carapax (head inside)
Reduced thorax and abdomen
AMPHIPODA
(peracarida)
Scrapers, predators
Legs oppositely oriented
No carapax
Compound eye
equally important Antennae
Abdominal podia
Furcal podia
No larvae
Marsupium
EUPHAUSIACEA
Filter feeders
No carapax
Compound eyes
A 1 biramous
Abdominal podia
Furcal podia
External visible gills
Larvae
MYSIDACEA
(peracarida)
Filter feeders
carapax
Compound eyes
Antennae equally important
A 1 biramous
Marsupium
Abdominal podia
Furcal podia
statocysts
CUMACEA
(peracarida)
detritivores
not complete Carapax
Compound eyes coupled
Antennulae > Antennae
Marsupium
Naked abdomen
Furcal podia
Surface currents
Deep current
Deep-Surface
Biotic exchanges
THE CONNECTING COASTAL AREAS NETWORK
THE HYPERBENTHOS
ASSOCIATION OF SMALL ANIMALS LIVING
IN THE WATER LAYER CLOSE (1 m) TO THE SEA BED
AUTOCHTHONOUS SPECIES
PLANKTONIC SPECIES (SEASONAL)
MEIOBENTHIC SPECIES (DIAL)
Mysidacea
Cumacea
Decapoda larvae
0.5
0.05
1.5
0.00
0.1
0-20 cm
800.0
3.3
7.6
1.9
4.3 specimens / 1000 litres
Copepoda
Amphipoda
20-40 cm
sand beds (Bieri & Tokioka, 1968)
106-142 cm
28-64 cm
0.01-1.69
(21 species)
6.80 – 10.65 specimens / 1000 litres
(87 species)
-350 m (Huberdou & Brunel, 1968)
Autochthonous Components:
Amphipoda
Mysidacea
Cumacea
Copepoda
Chaetognatha
Oligomeres
Cuticled
Pseudocoelomates
Protostomes
No larvae
Hermaphrodites
Predators
Hyperbenthos possibly affects the
plankton composition because some
mysidaceans feed on cysts
Hyperbenthos appears as fundamental
resource for demersal fish juveniles
and it appears surprisingly abundant
NEUSTON
Y.P. Zaitsev, 1971 114 cit
Naumann (1917): bacteria, euglenids,
chlamydomonads, amebas and other minute
organisms inhabiting the surface film of small
ponds and puddles
Zernov (1934): also in
marine waters
The upper 5 cm of the sea contain great masses of
metazoans, protozoans and saprophytic bacteria. The
bacterio-neuston is hundreds or thousands times denser
than the bacterio-plankton.
The uppermost 10 cm of the sea absorb
about 50% of light arriving at the surface
Absorption of sun light at
Black sea surface
0 – 1 cm
0 – 5 cm
0 – 10 cm
20%
40
50
The most of the
biologically active
radiation (visible and UV)
stays in the first 5 cm
In the sea, the total amount of dead organic matter is 50 - 500
times greater than the living biomass
900
200
75 µm
The dead organic matter derives
from marine organisms
from land (river run off)
from atmosphere (rain)
from eolian transport
In any cases it accumulates
on the sea surface
Insects from land
Represent one of the most
important components of
the dead biomass
Far to 10s kilometres from
the coast
Boyant for days or weeks
Pollen, spores, and other
particulated organic
matter rain down on the
sea surface, and they do
not sink
The ANTIRAIN
concentrates at the
sea surface dead
organic matter from
the undelying world
Vertical distribution of dead Penilia avirostris and
Copepoda in the Black sea, August 1966
Layer
0-05 cm
5-25
25-45
480-500
1280-1300
1480-1500
ind.1000L
biomass %
1,152 16,261
47 34
270 6,725
11 29
367 5,566
15 18
190 3,833
8
9
315 5,400
13 10
161
6
The ANTIRAIN
concentrates at the
sea surface also gas
bubbles which
produce foam, rich
in biologivally active
molecules
The anatomy, behavior and feeding habits of many flying
species (birds and bats) show that they live mainly at the
expense of this superficial layer.
The feeding habit of fishing bats
is evolved at the expense of fish
staying at the superficial layer
Neuston organisms suffer a double
predation pressure in the uppermost layer of
the water column.
Such a risk is (evidently) counterbalanced
by some advantages ( abundance of food? )
organic material and organisms by
1 anti-rain
2 wind
Great energy from
3 sun light
Interactions with
4 water predators
5 air predators
The eu
neuston
The mero-neuston
The bentho-hypo-neuston
Mysidacea,
Cumacea,
Amphipoda,
Polychaeta,
Neuston composition
I
detritus, dead organisms, Eggs
II plankto-neuston
Bacteria
Tintinnina
Spumellaridae (Radiolaria)
Dinoflagellata (Noctiluca sp.)
Rotifera
larvae of mero-plankton
Copepoda larvae and juveniles
III euneuston
IV bentho-hypo-neuston
V ichthyoneuston