520 research outputs found
Especies de Chone Kroyer, 1856 (Polychaeta: Sabellidae) del Atlántico Oriental Central y Mar Mediterráneo
No full textA neotype specimen is designated for Chone acustica (Claparède, 1870) with a full description. The original descriptions of Chone arenicola Langerhans, 1880 and Chone collaris Langerhans, 1880, both from Madeira, did not include some details and incomplete or misleading information was provided, so both species are redescribed. Amendments to the description of Chone longiseta Giangrande, 1992 are also given together with the methyl green staining pattern of Chone usticensis Giangrande et al. 2006. Two new species are described: Chone gambiae sp. nov., from the Gulf of Naples and Chone dunerificta sp. nov., from the Gulf of Salerno. This study shows the distribution of Chone duneri Krøyer, 1856, and Chone filicaudata Southern, 1914, to be restricted to the Arctic seas and North Atlantic Ocean, respectively. Records from the Mediterranean Sea are found to be erroneous.Se designó el neotipo de Chone acustica (Claparède, 1870). Las descripciones originales de Chone arenicola Langerhans, 1880 y Chone collaris Langerhans, 1880, ambas de Madeira, no incluyen carácteres diagnósticos y la información proporcionada en otras contribuciones es incompleta, en este estudio ambas especies fueron redescritas. Se adicionaron carácteres diagnósticos a la descripción de Chone longiseta Giangrande, 1992, y se describió el patrón de tinción con verde de metilo de Chone usticensis Giangrande et al. 2006. Se describieron dos nuevas especies: Chone gambiae sp. nov., del Golfo de Nápoles y Chone dunerificta sp. nov., del Golfo de Salerno. Se restringió la distribución de Chone duneri Krøyer, 1856 para los mares del Ártico y Chone filicaudata Southern, 1914 para el Océano Atlántico Norte. Los registros de ambas especies para el Mar Mediterráneo son erróneos
The genus Demonax (Polychaeta, Sabellidae) in the Mediterranean Sea, with description of D. tommasi
No full textAs pointed out by Knight-Jones & Walker (1985), the
genus Demonax Kinberg has been largely ignored for the
last 100 years, due to Kinberg's (1867) diagnosis which
was a very narrow one. The genus is characterized by the
peculiar shape of companion setae (Johansson, 1925;
Rioja, 1962; Knight-Jones, 1983), while the shape of inferior
thoracic setae is very variable (Perkins, 1984).
Before considering the first of these characters, some
species with slender inferior thoracic setae were referred
to the Sabella L. genus (Banse, 1979), and species with
broadly hooded inferior thoracic setae were referred to
Potamilla Malmgren genus. For this reason, the species
Potamilla torelli Malmgren was wrongly reported within
Mediterranean fauna (Claparède, 1870; Lo Bianco, 1893;
Iroso, 1921; Giangrande, 1990).
At present 24 species are listed within the genus, of
which only D. brachychona (Claparède) and D.
tenuicollaris (Grube) are known for the Mediterranean
fauna (Knight-Jones, 1983; Knight-Jones et al., 1991).
The finding of several individuals belonging to the
genus Demonax along the Apulian coast (Adriatic Sea)
allowed a better definition of the species present in the
Mediterranean Sea, and the description of a new species
Clearance rates of Sabella spallanzanii and Branchiomma luctuosum (Annelida : Polychaeta) on a pure culture of Vibrio alginolyticus
No full textThe influence exerted by filter-feeding activity on bacterial density by two sabellid species from the Mediterranean Sea (Ionian Sea, Italy), Branchiomma lucluosum Grube and Sabella spallanzanii Gmelin (Annelida: Polychaeta) was investigated. Clearance rates and retention efficiencies were estimated utilizing the species Vibrio alginolyticus selected on account of previous field studies and its importance in fish Culture pathogenicity. The C-max was 43.2 +/- 2.63 L h(-1) g(-1) DW for B. luctuosum and 12.4 +/- 2.22 L h(-1) g(-1) DW for S. spallanzanii. The Retention efficiency was 98% corresponding to a removed bacterial biomass of 44.8 + 7.88 mu gC L-1 g(-1) DW for B. luctuosum and 70% corresponding to a bacterial biomass of 23.8 + 2.95 mu gC L-1 g(-1) DW for S. spallanzanii. Maximum retention was recorded after 20 min for the first species and after 30 min for the second one. Present laboratory experiments represent a contribution to the knowledge of the filtration activity of the two polychaetes, characterizing the filtration process on bacterioplankton. Both species resulted extremely efficient in removing V. alginolyticus from seawater in experimental tanks, thus confirming the previous data from the field studies and suggesting their employment as biofilters of microbially contaminated waters in intensive aquacultur
THE GENUS NEREIS L., 1758 (POLYCHAETA, NEREIDIDAE): STATE OF THE ART FOR IDENTIFICATION OF MEDITERRANEAN SPECIES
No full textThe Genus Nereis L., 1758 (Polychaeta, Nereididae): State of the Art for Identification of Mediterranean Species. The existence of critical problems in the identification of species within the genus Nereis L., 1758 (Annelida Polychaeta: Nereididae) has led to several misidentifications within Mediterranean taxa. In the present paper we report a discussion on the Mediterranean species, with a re-examination of specimens collected along the Italian coasts. A redescription of each species is provided, pinpointing the diagnostic characters with detailed figures for easy identification. Old and recent synonymies are also discussed and a key for identification is provided
A new sponge-associated species, Syllis mayeri n. sp (Polychaeta : Syllidae), with a discussion on the status of S-armillaris (Muller, 1776)
No full textIn the framework of a study carried Out along the Belizean coasts, a new species of syllid. Syllis mayeri n. sp.. was found harboured by the sponge Ircinia strobilina. The description of this new taxon is given.. and compared to other similar congeneric species and to some Mediterranean material from the Southern Italian coast ascribed to S. armillaris. The new species is characterized by some stout compound chaetae with ypsiloid appearance, whose probable use for attaching to the host is hypothesized. Other diagnostic features are antennae, tentacular cirri and dorsal cirri of the anterior portion of the body that are longer than in similar, compared species. Moreover, the mid-body dorsal cirri are typically spindle-shaped. A discussion on the status of some sponge-associated taxa from tropical and Subtropical seas attributed to the so-called cosmopolitan S. armillaris is also give
A new species of sphaerosyllis (polychaeta, syllidae, exogoninae) from the coasts of italy and cyprus (eastern mediterranean sea)
No full textThe faunistic analysis of hard and soft benthic materials collected from the Marine Reserve of Porto Cesareo (Ionian Sea, Salento Peninsula, Italy) and the coast of northern Cyprus (Levant Sea) revealed a new species of Sphaerosyllis, S. boeroi sp. n. (Polychaeta, Syllidae, Exogoninae). This species is mainly characterized by having compound chaetae with discernable subdistal spine, a strong dorso-ventral gradation in size of blades throughout the body, elongated slender blades of superior compound chaetae on anterior and middle parapodia, parapodial glands with fibrillar material, and the distributional pattern of papillae on the body surface. Sphaerosyllis boeroi is described and compared to the other morphologically similar species, with emphasis on its ecological and reproductive patterns. © 2005 Taylor & Francis Group, LLC.Two of the Authors (L.M. and A.G.) wish to thank Drs Caterina Longo, Mariella Mercurio and Carlotta Nonnis Marzano from the University of Bari, and Dr. Cataldo Pierri from the University of Lecce for their help during the sampling phase. The other Author (M.E.Ç.) also thanks the crews and scientific personnel of the R/V K. PIRI REIS for their help in obtaining benthic samples, and TUBITAK (NATO-B1 Programme) for the financial support that enabled him to visit some research stations in Italy to make this collaboration possible. -
End effects in linear tubular motors and compensated position sensorless control based on pulsating voltage injection
No full textThe sensorless position control of permanent-magnet (PM) synchronous motors can be successfully implemented by superimposing a high-frequency voltage signal on the control voltage. In this paper, the position estimation is obtained by means of a high-frequency sinusoidal voltage signal injected along the estimated d-axis. Several methods proposed in the literature obtain the position estimation by tracking the zero condition of the high-frequency q current component. We propose a new approach that also exploits the d-axis high-frequency current component and allows working with injected voltage signal of reduced amplitude, thus reducing noise and additional losses. The main contribution of this paper relies in the compensation of the motor end effects due to the finite length of the tubular motor armature. These effects must be taken into account in the motor modeling because they cause an error in the position estimation that varies with the motor position. The modeling of the phenomenon and a proper compensation technique are proposed in this paper. Last, a simplified integral-type controller is used to estimate motor position instead of the commonly adopted proportional-integral controller plus integrator, and this requires a low-effort design. Experiments on a linear tubular PM synchronous-motor prototype are presented to validate the theoretical analysis and evidence the feasibility of the proposed sensorless technique
Chone usticensis Giangrande & Licciano & Castriota 2006, sp. nov.
No full textChone usticensis sp. nov. Figures 2 –4 Material examined Type material: Holotype, MNCN 16.01/10325, collected by L. Castriota at station A, 38°41.50’ N 13°09.78’ E, in November 1997, at 50 m depth on a softbottom mainly composed of medium sand, biogenic and volcanic particles, together with a significant amount of red calcareous algae. Paratypes, MNCN 16.01/10326, 3 specimens from the same station. Nontype material from the same locality (held in the personal collection of A. Giangrande): station A, 20 specimens Nov 96, 11 specimens July 97, 25 specimens November 97; station B, 48 specimens November 96, 40 specimens July 97, 59 specimens November 97; station C, 35 specimens November 96, 8 specimens July 97, 522 specimens November 97. Description Holotype complete, with 8 thoracic and 30 abdominal chaetigers (Fig. 2A). Branchial crown length 10 mm, total thoraxabdomen length 20 mm, maximum width 2.5 mm. Branchial lobes each with 10 fully developed radioles and one to two ventral radiolar appendages (Fig. 3A); radioles with palmate membrane for less than half of their length; radiolar flanges present distally to palmate membrane, but with radioles terminating as very long filaments (Fig. 2B). All pinnules of similar length. Radiolar skeleton axis composed of two rows of cells; outer surfaces of radioles flat. Dorsal lips pointed, longer than wide, radiolar appendages not visible, with one or two pinnular appendages. Ventral lips rounded, with radiolar appendage (Fig. 3A, B). Collar high with a middorsal narrow gap, and slightly higher ventrally (Fig. 2C), ventral lobe of anterior peristomial ring pointed and extending slightly beyond ventral collar margin (Fig. 2D). Thoracic notopodia in chaetiger 1 with 4 narrowly hooded chaetae. Notopodial fascicle from chaetigers 2–8 with superior group of 3–4 elongate narrowly hooded chaetae (Fig. 4C) and inferior group with 4–5 paleate chaetae posteriorly and 4–5 bayonet type anteriorly. Paleate chaetae with long tip (Fig. 4D). Neuropodial acicular uncini in number of about 13 per torus, with a series of small teeth of similar size over the main fang, with hood present, and breast only developed as slight swelling; handles very long (Fig. 4E, F). Abdominal neuropodial fascicles with modified, elongate narrowly hooded chaetae, longer in the posterior segment (Fig. 4A, B). Abdominal notopodia with 12–13 avicular uncini, with main fang surmounted by 5–6 rows of small teeth, breast rectangular, not extending beyond distal end of proximal tooth, handles absent. Intertorus variation in morphology present, with uncini from anterior abdominal segments as in Fig. 4H, and uncini from posterior abdominal segments as in Fig 4I. Intratorus variation present as well (Fig. 4G). Pygidium triangular with long cirrus (Fig. 2A, E). Thoracic ventral glandular shields visible in thoracic chaetigers. Body cream coloured. Tube not observed. Remarks Chone usticensis together with another Mediterranean species, C. filicaudata Southern, 1914, and C. americana Day, 1973, have a pygidial cirrus filament. Chone usticensis and C. filicaudata differ in the radiolar flanges which in C. filicaudata are developed until the end of radioles, in the length of palmate membrane, shorter in C. usticensis, in the shape of the paleate chaetae, wider in C. usticensis, and in the shape of the anterior peristomial ring lobe, entire and not incised in C. usticensis. Concerning the latter feature, C. usticensis is similar to C. americana, but differs in the shape of the thoracic uncini, which in C. americana are provided with teeth of unequal size above the main fang (TovarHernández 2005), in the shape of the collar, ventrally lower in C. americana, in the shape of thoracic paleate chaetae, which has a longer tip in C. usticensis, and in the shape of abdominal uncini, which in C. americana have a smaller number of teeth over the main fang. Chone usticensis also shows similarity to some Mediterranean specimens previously collected and reported as Chone sp. (Giangrande 1992). However, the features of the branchial crown, a lower palmate membrane and a shorter filiform tips of the radioles, distinguishes this taxon from C. usticensis. Most of the specimens of the examined population were small sized (around 10 mm in total length). The holotype was selected from the bestpreserved larger specimens because we assume it to be an adult, although gametes were not detected. Oocytes in the abdomen have been observed in some nontype material of a similar size as the holotype. The number of dorsal pinnular appendages seems to vary according to the size of individuals, with only one in smaller (Fig. 3A), and two in larger specimens (Fig. 3B). Type locality Offshore on South Coast of Ustica Island at 38°41.50’ N 13°09.78’ E. Etymology The species is named after the type locality.Published as part of Giangrande, Adriana, Licciano, Margherita & Castriota, Luca, 2006, Description of Chone usticensis sp. nov. (Polychaeta, Sabellidae) from the Mediterranean Sea, pp. 51-58 in Zootaxa 1168 on pages 53-57, DOI: 10.5281/zenodo.264553
The Genus Nereis L., 1758 (Polychaeta, Nereididae): State of the art for identification of mediterranean species
No full textThe Genus Nereis L., 1758 (Polychaeta, Nereididae): State
of the Art for Identification of Mediterranean Species. The existence
of critical problems in the identification of species within the genus
Nereis L., 1758 (Annelida Polychaeta: Nereididae) has led to several
misidentifications within Mediterranean taxa. In the present paper we
report a discussion on the Mediterranean species, with a re-examination
of specimens collected along the Italian coasts. A redescription of
each species is provided, pinpointing the diagnostic characters with
detailed figures for easy identification. Old and recent synonymies are
also discussed and a key for identification is provided
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