scholarly journals Natural diet of deep-water rose shrimp in the Beni-Saf Bay (Western Algeria)

2020 ◽  
Vol 10 (4) ◽  
pp. 109-115
Author(s):  
A.M. Benallal ◽  
A. Baaloudj ◽  
A. Kerfouf
Keyword(s):  
Deep Water ◽  
Decapod Crustacean ◽  
Average Frequency ◽  
Western Mediterranean ◽  
Natural Diet ◽  
Wide Range ◽  
Western Algeria ◽  
Males And Females ◽  
The Rose ◽  
Faunistic Composition

The deep-water rose shrimp, Parapenaeus longirostris (Lucas, 1846) is one of the Decapod crustacean species that is targeted by coastal and deep-sea demersal fisheries in the western Mediterranean, in the Algerian west coast in particular. Despite its socio-economic importance and commercial interest across the country, there were only few studies focusing on its biology and ecology and no species development plan has been drawn up for now. Our study of the rose shrimp diet was based on the analysis of the faunistic composition of the ingested prey. Seasonal sampling was carried out at Beni Saf port (western Algeria) during 2018-2019, from landings from inshore trawling fisheries. A total of 641 individuals were analyzed, while taking account of males and females and size classes. Results of stomach content analyzes showed a wide range of benthic and endobenthic species. Crustacea are the preferred prey (F=77.69%), followed by Foraminifera, Annelida Polychaeta, and Mollusca with respective frequencies of (77.22%, 58.50% and 52.73%). Radiolaria, Porifera and Echinodermata represent a less important part in the diet of this species and constitute accidental prey, whose frequency is less than 10%. Benthic organisms with silt ingest the plant and various debris, which are the secondary prey with an average frequency of 14.81%.

scholarly journals Re-Evaluation of the Podosphaera tridactyla Species Complex in Australia

2021 ◽  
Vol 7 (3) ◽  
pp. 171
Author(s):  
Reannon L. Smith ◽  
Tom W. May ◽  
Jatinder Kaur ◽  
Tim I. Sawbridge ◽  
Ross C. Mann ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Powdery Mildew ◽  
Species Complex ◽  
Taxonomic Revision ◽  
Stone Fruit ◽  
Prunus Species ◽  
Wide Range ◽  
Unidentified Species ◽  
The Rose ◽  
Generation Sequencing

The Podosphaera tridactyla species complex is highly variable morphologically and causes powdery mildew on a wide range of Prunus species, including stone fruit. A taxonomic revision of the Po. tridactyla species complex in 2020 identified 12 species, seven of which were newly characterised. In order to clarify which species of this complex are present in Australia, next generation sequencing was used to isolate the fungal ITS+28S and host matK chloroplast gene regions from 56 powdery mildew specimens of stone fruit and ornamental Prunus species accessioned as Po. tridactyla or Oidium sp. in Australian reference collections. The specimens were collected in Australia, Switzerland, Italy and Korea and were collected from 1953 to 2018. Host species were confirmed using matK phylogenetic analysis, which identified that four had been misidentified as Prunus but were actually Malusprunifolia. Podosphaera species were identified using ITS+28S phylogenetic analysis, recognising three Podosphaera species on stone fruit and related ornamental Prunus hosts in Australia. These were Po.pannosa, the rose powdery mildew, and two species in the Po. tridactyla species complex: Po. ampla, which was the predominant species, and a previously unidentified species from peach, which we describe here as Po. cunningtonii.

scholarly journals Sources of variation in the feeding ecology of the piked spurdog (Squalus megalops): implications for inferring predator–prey interactions from overall dietary composition

2005 ◽  
Vol 62 (6) ◽  
pp. 1076-1094 ◽  
Author(s):  
J. Matías Braccini ◽  
Bronwyn M. Gillanders ◽  
Terence I. Walker
Keyword(s):  
Spatial And Temporal Variation ◽  
Dietary Composition ◽  
Bootstrap Analysis ◽  
Predator Prey ◽  
Ecological Relationships ◽  
Wide Range ◽  
Opportunistic Predator ◽  
Sources Of Variation ◽  
Males And Females ◽  
Prey Items

Abstract Sources of variation in dietary composition were examined in the piked spurdog (Squalus megalops). The species is an opportunistic predator that consumes a wide range of prey items. When importance of prey was measured by weight or occurrence, S. megalops preyed largely on molluscs and teleosts. However, when number of prey was considered, the main items were crustaceans. A bootstrap analysis showed that considerable variability can be expected in the importance of prey items in the species' overall diet. Regional, seasonal, and ontogenetic differences in dietary composition were found, but there were no differences between mature and immature sharks or between males and females. The spatial and temporal variation in diet exhibited by S. megalops and the intrinsic natural variability of the dietary composition of this opportunistic predator suggest that studies that infer predator–prey interactions from overall diet are likely to miss information on the ecological relationships among species and thus account for only part of these interactions.

scholarly journals Deep-water macroalgal-dominated coastal detritic assemblages on the continental shelf off Mallorca and Menorca (Balearic Islands, Western Mediterranean)

2012 ◽  
Vol 55 (5) ◽  
Author(s):  
Sergi Joher ◽  
Enric Ballesteros ◽  
Emma Cebrian ◽  
Noemí Sánchez ◽  
Conxi Rodríguez-Prieto
Keyword(s):  
Continental Shelf ◽  
Deep Water ◽  
Western Mediterranean ◽  
Balearic Islands

Assessment of the deep water trawl fishery off the Balearic Islands (western Mediterranean): from single to multi-species approach

Hydrobiologia ◽  
2011 ◽  
Vol 670 (1) ◽  
pp. 67-85 ◽  
Author(s):  
Beatriz Guijarro ◽  
George Tserpes ◽  
Joan Moranta ◽  
Enric Massutí
Keyword(s):  
Deep Water ◽  
Western Mediterranean ◽  
Balearic Islands ◽  
Trawl Fishery

scholarly journals Tracers confirm downward mixing of Tyrrhenian Sea upper waters associated with the Eastern Mediterranean Transient

2010 ◽  
Vol 7 (4) ◽  
pp. 1533-1557
Author(s):  
W. Roether ◽  
J. E. Lupton
Keyword(s):  
Deep Water ◽  
Time Scale ◽  
Eastern Mediterranean ◽  
Western Mediterranean ◽  
The Other ◽  
Tyrrhenian Sea ◽  
Convective Mixing ◽  
Deep Waters ◽  
Major Process ◽  
Gibraltar Strait

Abstract. Observations of tritium and 3He in the Tyrrhenian Sea, 1987–2009, confirm the enhanced convective mixing of intermediate waters into the deep waters that has been noted and associated with the Eastern Mediterranean Transient in previous studies. Our evidence for the mixing rests on increasing tracer concentrations in the Tyrrhenian deep waters, accompanied by decreases in the upper waters, which are supplied from the Eastern Mediterranean. The downward transfer is particularly evident between 1987 and 1997. Later on, information partly rests on increasing tritium-3He ages; here we correct the observed 3He for contributions released from the ocean floor. The Tyrrhenian tracer distributions are fully compatible with data upstream of the Sicily Strait and in the Western Mediterranean. The tracer data show that mixing reached to the bottom and confirm a cyclonic nature of the deep water circulation in the Tyrrhenian. They furthermore indicate that horizontal homogenization of the deep waters occurs on a time scale of several years. Various features point to a reduced impact of Western Mediterranean Deep Water (WMDW) in the Tyrrhenian during the enhanced-convection period. This is an important finding because it implies less upward mixing of WMDW, which has been named a major process to enable the WMDW to leave the Mediterranean via the Gibraltar Strait. On the other hand, the TDW outflow for several years represented a major influx of enhanced salinity and density waters into the deep-water range of the Western Mediterranean.

scholarly journals Decapod crustacean assemblages off the West coast of central Italy (western Mediterranean)

2007 ◽  
Vol 71 (1) ◽  
pp. 19-28 ◽  
Author(s):  
Emanuela Fanelli ◽  
Francesco Colloca ◽  
Giandomenico Ardizzone
Keyword(s):  
West Coast ◽  
Central Italy ◽  
Decapod Crustacean ◽  
Western Mediterranean ◽  
The West
Sign in / Sign up

Export Citation Format

Share Document