International Journal of Marine Science 2015, Vol.5, No.19, 1-10
6
4 - yellow double (0.33), 5 - red (0.31). Analysis of
the average distribution of carotenoids in the tissues of
R. venosa
showed that most of them fell on the gonads
of both sexes mollusks (61-65%). Rf indicators
suggest that they are present: 1 - β-carotene, 3 -
pectenolon, 4 - a mixture diatoxanthin and alloxanthin,
5 - mitiloxsanthin. In generative tissue
R. venosa
alloxanthin clearly dominates in the amount with their
esters it is more than 90% of carotenoids (Shulman et
al, 2014).
Analysis of the average distribution of carotenoids in
the tissues of
R. venosa
showed that the main
proportion (61-65%) accounted for the gonads of both
sexes molluscs. During spawning, the carotenoid
content in the gonads of males maximum and almost
10 times their values in females. The main part of the
carotenoids in the remaining tissues in the digestive
gland concentrated where their contents are almost 2
times lower than in the gonads. The level of
carotenoids in the foot clam was negligible (3-9% of
the amount of carotenoids) (Shulman et al, 2014).
These data are consistent with the visual evaluation of
the ratio of pigments in various tissues of different
sexes at the time of research. Obviously, the formerly
it is a pigment carotenoids, determines the color of
tissue
R. venosa
and the color of the gonads most of
all. Pink and even red color corresponding to specific
carotenoids on TLC chromatograms, probably
determine the color of the gonads of females anomaly
(Figure 4). Various shades of brown and somewhat
red in color gonad and digestive gland are likely
determined by melanin. One of the probable reasons
for changing the composition of pigments in
R. venosa
is a change in the spectrum of power that occurred in
the majority of the population of Crimea in the late
1990s - early 2000s (Bondarev, 2010, 2014).
Trophic system, "mollusc-filter feeder → mollusc
predator" is considered as an example of carotenoids
bivalves and
R. venosa
. Basic Rapana carotenoids
coincide with those of the mussels, in this connection
it may be assumed that their presence is due normal
accumulation rather than metabolic transformation.
Prevailing in the Rapana gonads alloxanthin is typical
algal pigment and get it predatory
R. venosa
can only
when feeding bivalves. The initial
R. venosa
main
food -
M. galloprovincialis
identified 20 carotenoids
(about 99% of composition), in
R. venosa
- only 6
carotenoids (about 85% of the composition). A
significant part of the mussel carotenoids underwent
metabolic transformation
R. venosa
(Shulman et al,
2014).
The population which is dominated by the colors and
shades of orange-red "carotenoid line»gonads (Figure
7) inhabits the rocky surface Cape Theophane where
R.
venosa
feeds mainly bivalves genera
Mytilus
and
Mytilaster
. It is obvious that this explains the
predominance of males with orange-red-brownish
gonads in the area even in 2014. The presence of
single males with dark brown gonads in this local
population can be explained that these individuals
previously lived on sand bottom and feed mainly on
Ch. gallina
. In favor of this version is not typical of
rock populations light color shells these single
individuals but is characteristic of populations living
on sandy bottom. In turn, the presence in the Blue Bay
population of individuals “carotene line” (Figure 8,
left) is a consequence of interaction with adjacent
local populations and ecological communities living
on the rocks.
In the investigated bays in
R. venosa
food range
prevail bivalves Veneridae and Cardiidae, average size
of about 1.5 cm that essentially limits the growth of
the predator, and also provide the specific composition
of the pigments. Data on quantitative and qualitative
composition of pigments are absent but it is possible
that they are differ significantly from pigments
M.
galloprovincialis
and this is the cause of the gonads
color change and the formation of brown "melanin
line" (Figure 6, 8, right side). Biochemical differences
in ecologically different groups of bivalves allow us to
assume because in
Anadara kagoshimensis
(Tokunaga,
1906) (misnamed
A. inaequivalvis
) there are only 6 of
carotenoids (more than 90% of the composition)
against 20 in
M. galloprovincialis
(Shulman et al,
2014).
A. kagoshimensis
– invader that takes in the
Black Sea an increasingly significant role is now one
of the main
R. venosa
food objects in some areas.
However,
R. venosa
internally switched to nutrition
bivalves inhabitants sandy bottom about 15 years ago
when en masse Rapana with basic brown gonads are
marked only after 2012. Fact that changes in the color
of the gonads occurred with sufficiently long delay of
approximately 10-15 years, possibly indicative of their
