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Biological Evidence 2013, Vol.3, No.2, 4-11
http://be.sophiapublisher.com
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Scientific Discovery Open Access
Shell Color Allelic Lines of
Rapana venosa
(VALENCIENNES, 1846)
Igor P. Bondarev
Benthos Ecology Department, Institute of Biology of the Southern Seas (IBSS), Ukrainian National Academy of Sciences (NASU), Nakhimov av., 2,
Sevastopol, 99011, Ukraine
Corresponding author email: igor.p.bondarev@gmail.com
Biological Evidence 2013, Vol.3, No.2 doi: 10.5376/be.2013.03.0002
Received: 30 Nov., 2012
Accepted: 15 Dec., 2012
Published: 17 Dec., 2012
© 2013 Bondarev, This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use,
distribution, and reproduction in any medium, provided the original work is properly cited.
Preferred citation for this article as:
Bondarev, 2013, Shell Color Allelic Lines of
Rapana venosa
(VALENCIENNES, 1846), Biological Evidence, Vol.3, No.2 4-11 (doi: 10.5376/be.2013.03.0002)
Abstract
Rapana venosa
shell outer background color and color patterns variation were investigated. It is stated that color diversity
spectrum is produced by combination of two different genes and their alleles. Dominant and recessive alleles are determined by
proportional frequency of associated shell color type reflection.
Keywords
Allele;
Rapana venos
; Shell color patterns
Distribution of pigment in the Rapana shell matches its distribution in the epithelial cells of outer surface of
mantle, which is clearly visible as pigment bands going perpendicular to the edge of the mantle. Accordingly, the
characteristic element of the Rapana shell outer part pigment pattern are spiral dark brown (dashed) lines located
on the shell spiral ridges (Bondarev, 2010). Based on the images and descriptions of the characteristic form of
native Rapana (Bogdanov, 1993, Habe, 1975; Kira, 1965) and Rapana from recently occupied areas (Bogdanov,
1993, Bondarev, 2010; Cossignani, 2011; ICES 2004; Kantor, 2006; Kerckhof et al, 2006; Lanfranconi et al.,
2009), we can conclude that this color pattern element, combined with gray-beige or brown in different shades and
color intensity of the background, creates
Rapana venosa
typical color form. Data from our present study also
confirms this statement.
Rapana venosa
shows a wide range of color and pattern on the shell outer part of expressed melanism to albinism.
This phenomenon is inherent for the Black Sea metapopulation (Bondarev, 2010), and known from the native
R.
venosa
range also (Kira, 1965). There is a genetically determined individual potential of a certain color type
formation. Adult individuals’ color type coincides with the intensity of the larval shell color: the darkest
protoconch corresponds negroid color form and the most light colored - to albinist form; and the color intensity of
the typical color form specimens matches the protoconch color intensity (Bondarev, 2010). During the shell
growing process the protoconch use to be lost, and the spire top use to be discolored and destroyed. Therefore, it is
impossible to show the connection between the initial potential and the mature shell color.
Meanwhile, analysis of adult individuals’ color variability from a large amount of data also provides some
interesting results as presented below.
More the 2 000 specimens from different regions of the Black Sea, several from Azov Sea (Photo slide 1) and 15
specimens from Sea of Japan were examined. Specimens from other regions pictured in the referenced literature
compared with the available ones.
To ensure the accuracy, the research was carried out mainly on the basis of analysis of mollusk shells from one
and the same population. For this purpose, on summer of 2012 the author studied and collected
R. venosa
among
local Blue Bay population in the vicinity of Sevastopol. Sampling author (Photo slide 2) held during snorkeling in
a mask and flippers at depths of 5~8 m. The population living on sandy bottom is characterized with low degree of
shells’ surface encrustation, which makes the cleaning of shells surface to be with the least possible effort. Of
about 600 specimens collected and analyzed, up to 300 were selected for photography. The most informative
pictures are illustrated in this paper. Photographing objects and their layout on the plateau were made. The images