Volume 9, Number 2
Published online 29/12/2012
Life cycle and feeding of Bougainvillia superciliaris (L. Agassiz, 1849) (Cnidaria: Hydrozoa: Filifera) in the White Sea
Moscow State University, Faculty of Biology, 1-12 Leninskie Gory, 119991, Moscow, Russia.
ABSTRACT: The life cycle of Bougainvillia superciliaris (Hydrozoa: Cnidaria) in the White Sea was investigated by means of laboratory and field surveys. The peculiarities of medusae and hydroids in the White Sea were the same as compared with recent species description near the coast of Europe. The creeping colonies were observed in the sublittoral zone all the year. There was a variety of zooplankton preys in the stomachs of medusae and polyps in the Sea. The early polyps can ingest only a small prey. But the mature polyps had a broad prey composition in the stomachs and predated both zooplankton and bottom preys. Medusae had a broad prey composition in the stomachs too but caught only zooplankton preys. A prey selection index “C” was positive and significant for barnacle nauplii and copepods Microsetella norvegica. In experiments medusae caught crustaceans mainly. Medusae buds appeared in the spring under the ice. The spawning of medusae occured in June when the temperature in the Sea is 10–12 °C. We discuss the life cycle of B. superciliaris as compared with temperature and food supply in the White Sea.
How to cite this article: Prudkovsky A.A. 2012. [Life cycle and feeding of Bougainvillia superciliaris (L. Agassiz, 1849) (Cnidaria: Hydrozoa: Filifera) in the White Sea] // Invert. Zool. Vol.9. No.2. P.71–90 [in Russian, with English summary].
The Lymnaeid genus Catascopia Meier-Brook et Bargues, 2002 (Mollusca: Gastropoda: Lymnaeidae), its synonymy and species composition
Museum of Siberian Aquatic Molluscs, Omsk State Pedagogical University, 14 Tukhachevskogo Emb., Omsk, 644099, Russian Federation.
ABSTRACT: The lymnaeid genus Catascopia Meier-Brook et Bargues, 2002 with the type species Limnaea catascopium Say, 1817 was emerged on the basis of molecular data exclusively. It contains at least four species distributed in the Holarctic region. However, as many as three generic names older than Catascopia are available for the designation of the lymnaeid clade including L. catascopium: Polyrhytis Meek, 1876, Ladislavella B. Dybowski, 1913, and Walterilymnaea Starobogatov et Budnikova, 1976. It is shown that the name Ladislavella should be used for this purpose rather than the oldest one, Polyrhytis, since the latter is based on the fossil species and it is impossible to establish the molecular affinity of its type species with recent lymnaeids. Two new synonymies are proposed: Catascopia = Ladislavella syn.n. and Catascopia = Walterilymnaea syn.n.). Morphologically, there are two distinct groups of species within Ladislavella: one includes species distributed in Northern Eurasia, and other contains species distributed in North America and the Asian part of the Beringia. The conchological and anatomical differences between these groups allow to consider them as two subgenera of Ladislavella: Ladislavella s.str. (type species Leptolimnaea terebra var. sorensis W. Dybowski, 1913 = Limnaea palustris var. terebra Westerlund, 1885), and Walterilymnaea (type species Limnaea catascopium Say, 1817).
How to cite this article: Vinarski M.V. 2012. The Lymnaeid genus Catascopia Meier-Brook et Bargues, 2002 (Mollusca: Gastropoda: Lymnaeidae), its synonymy and species composition // Invert. Zool. Vol.9. No.2. P.91–104.
Dialychone and Paradialychone (Polychaeta: Sabellidae) from the Mediterranean Coast of Egypt with description of Dialychone egyptica sp.n.
S.A. Selim1, A.V. Rzhavsky2, Ò.À. Britayev2
1National Institute of Oceanography and Fisheries, El-Anfoushy, Kayet-Beh, Alexandria, Egypt.
2A.N. Severtsov Institute of Ecology and Evolution, RAS, Leninskij Prospekt 33, Moscow, Russia, 119071.
ABSTRACT: A new species of Dialychone, D. egyptica sp.n. (Sabellidae) is described from the Mediterranean Coast of Egypt. The material was collected from soft bottom at 60 m depth. It is unique among the genus in having an abdominal glandular ridge on chaetiger 13. The new species is also characterized by having pygidial cirrus, medium sized radiolar tips and long radiolar pinnules, anterior peristomial ring lobe incised and exposed beyond collar, a trapezoidal ventral collar shield, and paleate chaetae with long mucro. The distributions of Dialychone collaris (Langerhans, 1880), D. usticensis (Giangrande et al., 2006), D. dunerificta (Tovar-Hernández et al., 2007), and Paradialychone gambiae (Tovar-Hernández et al., 2007) along the Mediterranean coast of Egypt are also presented. P. gambiae reported for the first time in the Egyptian coasts, while D. dunerificta was previously recorded as Chone duneri Malmgren, 1867.
How to cite this article: Selim S.A., Rzhavsky A.V., Britayev T.A. 2012. Dialychone and Paradialychone (Polychaeta: Sabellidae) from the Mediterranean Coast of Egypt with description of Dialychone egyptica sp.n. // Invert. Zool. Vol.9. No.2. P.105–114.
Redescription and biology of Cossura pygodactylata Jones, 1956 (Polychaeta: Cossuridae) in the White Sea
A.E. Zhadan, E.V. Vortsepneva, A.B. Tzetlin
White Sea biological station, Biological faculty, Moscow State University, Moscow 119234, Russia.
ABSTRACT: Cossurids are quite abundant on soft substrata in the White Sea. Adult and juvenile specimens were studied using light and scanning electron microscopy. Originally the White Sea species was referred to Cossura longocirrata Webster et Benedict, 1887 but the present study revealed its affiliation to the close species C. pygodactylata Jones, 1956. Lateral organs are described for the first time in cossurids. Juveniles differ from adults by the presence of a prototroch, the pygidium without appendages, and hardly detectable division of the body into regions. Population size structure was investigated in four samples taken from July to November. Size-frequency histogram showed a bimodal distribution.
How to cite this article: Zhadan A.E., Vortsepneva E.V., Tzetlin A.B. 2012. Redescription and biology of Cossura pygodactylata (Polychaeta: Cossuridae) in the White Sea // Invert. Zool. Vol.9. No.2. P.115–125.
The first species of Actiniaria, Spongiactis japonica gen.n., sp.n. (Cnidaria: Anthozoa), an obligate symbiont of a glass sponge
N.P. Sanamyan1, K.E. Sanamyan1, K.R. Tabachnick2
1 Kamchatka Branch of Pacific Geographical Institute, Far-Eastern Branch of the Russian Academy of Sciences, Partizanskaya Str. 6, 683000 Petropavlovsk-Kamchatsky, Russia.
2 P.P. Shirshov Institute of Oceanology, Russian Academy of Sciences, Nakhimovsky Pr. 36, 117997 Moscow, Russia.
ABSTRACT: Spongiactis japonica, a new genus and species of Actiniaria, an obligate symbiont of hexactinellid sponge is described from Sagami Bay, Japan, Pacific Ocean. Numerous small specimens of this sea anemone live in the caves in a superficial layer of the sponge Hyalonema sieboldi and probably reproduce asexually. The species has no acontia and it is taxonomically related to Actinoscyphiidae (which members are believed have lost acontia) and to Hormathiidae (comprising species possessing acontia) but cannot be accommodated in either family. It is therefore assigned to the new family Spongiactinidae fam.n. The two related families, Actinoscyphiidae and Hormathiidae may well be united.
How to cite this article: Sanamyan N.P., Sanamyan K.E., Tabachnick K.R. 2012. The first species of Actiniaria, Spongiactis japonica gen.n., sp.n. (Cnidaria: Anthozoa), an obligate symbiont of a glass sponge // Invert. Zool. Vol.9. No.2. P.127–141.
Identification key for Nephtyidae (Polychaeta) of the Eastern Atlantic and the North Polar Basin
N.Yu. Dnestrovskaya1, I.A. Jirkov2
Department of Hydrobiology, Moscow Lomonosov State University, 119899, Moscow, Russia.
ABSTRACT. The new user-friendly identification key for Nephtyidae of the Eastern Atlantic and the North Polar Basin is proposed.
How to cite this article: Dnestrovskaya N.Yu., Jirkov I.A. 2012. Identification key for Nephtyidae (Polychaeta) of the Eastern Atlantic and the North Polar Basin // Invert. Zool. Vol.9. No.2. P.143–150.