World Congress of Malacology Antwerp ... - Unitas Malacologica

Fasciolariidae due to the peculiar radula of the single species, Troschelia berniciensis (King, 1846).
Conversely, Bouchet & Warén classified it in the Buccinidae, interpreting the lateral teeth with
multiple uniform cusps on the lateral teeth in some Buccinidae.
To elucidate phylogenetic relationships of Troschelia with the families Buccinidae and
Fasciolariidae, morphological and anatomical features were studied, and partial sequences from the
mitochondrial 16S rRNA gene were analyzed for Troschelia berniciensis and a number of buccinid
and fasciolariid taxa. Troschelia berniciensis is anatomically very similar to other boreal
representatives of buccinids. The anatomy of the studied fasciolariids, representing five different
genera of three subfamilies, is in general very similar to that of Buccinidae, with a few unique
features of the digestive system, which are not known among buccinids. In the phylogenetic
hypothesis derived from the molecular data, including 16 buccinid and 4 fasciolariid taxa, Troschelia
is in the same clade with the tropical buccinids Pareuthria and Phos. The fasciolariid taxa form a
separate clade, yet making Buccinidae polyphyletic. Pisaniinae lie as a sister group to buccinidfasciolariid
clade, again suggesting a polyphyletic origin of the buccinids.
Morpho-phylogenetic analysis of the subfamily Colinae (Buccinidae, Neogastropoda)
Kosyan, Alisa R.
A. N. Severtsov Institute of Ecology and Evolution, Leninsky prospekt 33, 119071 Moscow, Russia,
Email: kosalisa@rambler.ru
Subfamily Colinae Gray, 1857 (Buccinidae, Neogastropoda) is the most abundant and diverse
buccinid group in the North-Western Pacific and Far-Eastern Seas of Russia. It includes several
conchologically similar genera or subgenera with unclear status and composition. Basing on 37
morphological and anatomical characters of 35 species attributed to Colus Röding, 1799, Plicifusus
Dall, 1902, Latisipho Dall, 1916, Aulacofusus Dall, 1918, Retifusus Dall, 1916, Retimohnia McLean,
1995 and Pararetifusus Kosuge, 1967 phylogenetic analysis was conducted.
Obtained majority rule consensus tree well resolves genera Plicifusus, Retifusus, Pararetifusus и
Aulacofusus. Genus Retimohnia appears to be junior synonym of the genus Retifusus. Analysed
species of geterogeneous genus Colus form paraphyletic group. Presented results demonstrate the
importance and opportunity of using anatomical characters for taxonomy of extremely diverse and
variable family Buccinidae.
Vesicomyidae (Bivalves): trends of morphological adaptations
Krylova, Elena 1 ; Sahling, Heiko 2
1. P.P. Shirishov Institute of Oceanology, Nakhimovskii pr., 36, Moscow, 117851, Russia,
Email: elen@ocean.ru
2. Research Center Ocean Margins, University of Bremen, Klagenfurter Straße, GEO-Building,
28359 Bremen, Germany,
Email: hsahling@uni-bremen.de
The term Vesicomyidae is used here in a wide definition considering not only "large clams", but also
"small vesicomyids", what is supported by preliminary results of recent molecular analysis. All
studies conducted so far indicate that the large vesicomyids possess obligate chemosymbiosis with
sulfur-oxidizing bacteria. In gills of "small vesicomyids" bacteria also were detected, but obligate
chemosymbiosis is not yet proved. The family comprises 94 described and about 15 yet unnamed
living species distributed from 77° N to 70°S at depths from 100 to 9050 m in reducing sulphide-rich
habitats. The family is highly morphologically disparate. Species range in length from 2.0 to 270
mm; shell shape varies from rounded to strongly elongate. There are differences in number of
ctenidial demibranchs, relative size of demibranchs, internal structure of ctenidia, structure of siphons
121