International Journal of Marine Science 2015, Vol.5, No.19, 1-10
3
yellow and pale orange (Mann et al., 2006). In the
Black Sea Agigea littoral area imposex females had
penis (1.14mm-6.94mm) and yellow-orange gonads
(Micu et al
.
, 2009). Thus the color of the gonads of
imposex females individuals approaching the color of
the gonads of young males by (Chuhchin, 1961a) and
it can be assumed that this is a consequence of
masculinization. Number of imposex females (IF) in
the western part of the Black Sea is approximately
30% the number of females (F: IF = 3.26:1) after
(Micu et al
.
, 2009), whereas in 4 out of 5 Chesapeake
Bay geographic regions examined the preponderance
of imposex females over ‘normal’ females (penis
length = 0) by at least a 2:1 ratio (Mann et al., 2006).
In our samplings the presence of even one female with
minimum penis size was not found. And the vast
majority of females had gonads in various shades of
yellow (Figure 3).
Figure 3
R. venosa
female soft bodies with normal gonad color
variants 2014 sampling areas (1) and (2) with indication of
individual age and the shell length: A-D – Blue bay (2), E-G –
Round bay (1), A – 4 years old, 60.0mm, B - 5 years, 58.0mm,
C – 7 years, 40.5mm, D – 8 years, 45.5mm, E – 10 years,
42.5mm, F - 10 years, 75.0mm, G – 12 years, 64.1mm
Females with abnormal coloration of gonads in our
collections were found sporadically but the variety of
colors is large enough (Figure 4) corresponding in
some individuals’ gonads normal (Figures 7, 8) or
abnormal males (Figure 5).
In individuals with abnormal coloration of gonads
there were no conchological differences. All females
with abnormal coloration of gonads were aged at least
5 years which corresponds the observation made for
imposex females were not among young aged individuals
Figure 4
R. venosa
female soft bodies with abnormal gonad
color variants of Blue bay 2012 (A, F) and 2014 (B-E, G)
sampling with indication of individual age and the shell length:
A – gonad cream with light orange staining, 6 years, 63.0mm,
B – orange with yellow grains, 5 years, 60.2mm, C – orange
with yellow grains, 8 years, 73.1mm, D – beige, 8 years,
68.0mm, E – dark orange, 6 years, 66mm.2, F – brick-red, 8
years, 68,5mm, G – rubicund, 7 years, 60.5mm
Figure 5
Rapana venosa
abnormal males with indication of
penis degree, gonad color, individual age and the shell length:
A - with a strongly reduced penis, beige color of the gonads, 3
years, 48.2mm, B - slightly reduced penis, brick-red gonads, 3
years, 54.1mm, C - normally developed penis, maroon gonads,
8 years, 66.8mm
(Mann et al., 2006). At the same time abnormal
coloration of gonads among males in our collections
marked the age of 3 years. And given the fact that in
our samplings for the study of the gonads individuals
aged 2 years or less among both sexes were less than
5%, then the question of the age of the initial
formation of abnormal coloration remains open.
Several individuals with reduced penis and abnormal
coloration of gonads of our collections (Figures 5A, B)
were males. Studying under the microscope showed
that the gonads of these specimens a significant
difference in color contain only male sex cells.
