Clearance rates of Sabella spallanzanii and Branchiomma luctuosum (Annelida: Polychaeta) on a pure culture of Vibrio alginolyticus

The influence exerted by filter-feeding activity on bacterial density by two sabellid species from the Mediterranean Sea (Ionian Sea, Italy), Branchiomma luctuosum 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 Cmax 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 μgC L-1 g-1 DW for B. luctuosum and 70% corresponding to a bacterial biomass of 23.8+2.95 μgC 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 aquaculture. © 2005 Elsevier Ltd. All rights reserved

Larval development and post-larval growth of Branchiomma bairdi (Annelida: Sabellidae) from a Mediterranean population

Branchiomma bairdi is a Caribbean fan worm introduced in several localities worldwide, including the Mediterranean Sea, where the species' range has rapidly expanded. Reproduction in B. bairdi was previously investigated in both extra-Mediterranean and Mediterranean areas, but no information is available on larval development and post-larval growth. In the present article, we examined these features for a population from the Mar Grande of Taranto (Ionian Sea). The species is hermaphrodite, and fertilization occurs in situ. Mucus seems to play an important role in fertilization, and also in preserving eggs before fertilization. The trochophore stage develops within the mucus and after hatching, larvae swim for about 3 d before settlement. The trochophore showed a distinct prototroch and two red dorsolateral larval eyes. The pelagic stage takes only 96 h even though prototroch is maintained after settlement, disappearing at 5 d, when larvae showed three chaetigers and branchial crown consisted of four radioles. Some interesting observations concerning changes in the morphology of chaetae and in the number of uncini during growth are also reported, together with discussion of the development of stylodes, an important diagnostic feature in Branchiomma species identification

11/08/1989 - Green Joins Eastern

Sabellidae is the second most diverse polychaete family in the Adriatic Sea, after Syllidae. Herein we report the updated list of the Sabellidae and Fabriciidae families in the Adriatic Sea deriving both from literature data and presently conducted researches in the northern Adriatic. During these researches polychaetes were sampled from three offshore soft-bottom and three coastal rocky shore stations. Among the analysed material three Sabellidae species are new records for the Adriatic fauna, while four Sabellidae and one Fabriciidae species were recorded for the first time in the northern part. Two new species were found and described: Amphicorina rovignensis spec. nov. and Megalomma pseudogesae spec. nov. These findings increase the number of Sabellidae taxa recorded in the northern Adriatic from 29 to 38. Our results point out the lack of the recent taxonomic studies in the area, but might also indicate the widening of the species areal. Taking into consideration that studies on only six stations raised the number of known sabellid taxa from the area by 31%, our results support the need for the regular taxonomic updating of the polychaete fauna in the northern Adriatic

Addition to the knowledge on Acromegalomma messapicum (Giangrande & Licciano, 2008) (Annelida: Sabellidae)

The genus Acromegalomma has been recently introduced as nomen novum for the polychaete genus Megalomma. Recently specimens of A. messapicum were collected from the coastal area of Civitavecchia (Tyrrhenian Sea, Italy) and re-collected from the type locality (Brindisi, Adriatic Sea, Italy) allowing us to examine additional fresh material and to add some useful morphological and biological information to the original description. The present data widens the distribution of the species. The possibility to examine several specimens of A. messapicum collected in different areas allowed us to state with certainty the absence of variability as concerns both the distribution of the radiolar eyes and the collar shape. The new findings revealed a colouration pattern present in the thorax and in the branchial crown, as well as the presence of large pygidial eyes previously not reported. Specimens have very broadly hooded chaetae, especially at the beginning of the abdomen, becoming more slender and therefore narrowly hooded, proceeding towards the end of the abdomen. This could explain the incorrect statement in the original description, of the presence of narrowly hooded abdominal chaetae as characterising A. messapicum. The present data also allowed some biological observations. Acromegalomma messapicum is gonocoric with eggs measuring about 120 mm in diameter. Most of the specimens were collected in cold months but ripe specimens were found in warm months. In addition a scheme of groups of Acromegalomma species modified from that previously proposed by different authors is given, where some taxa have been moved to different groups on the basis of a new interpretation of the collar features

Filtration of the Microalga Amphidinium carterae by the Polychaetes Sabella spallanzanii and Branchiomma luctuosum: A New Tool for the Control of Harmful Algal Blooms?

Harmful algal blooms (HABs) are extreme biological events representing a major issue in marine, brackish, and freshwater systems worldwide. Their proliferation is certainly a problem from both ecological and socioeconomic contexts, as harmful algae can affect human health and activities, the marine ecosystem functioning, and the economy of coastal areas. Once HABs establish, valuable and environmentally friendly control actions are needed to reduce their negative impacts. In this study, the influence exerted by the filter‐feeding activity of the two sabellid polychaetes Branchiomma luctuosum (Grube) and Sabella spallanzanii (Gmelin) on a harmful dinoflagellate was investigated. Clearance rates (C) and retention efficiencies were estimated by employing the microalga Amphidinium carterae Hulburt. The Cmax was 1.15 ± 0.204 L h−1 g−1 DW for B. luctuosum and 0.936 ± 0.151 L h−1 g−1 DW for S. spallanzanii. The retention efficiency was 72% for B. luctuosum and 68% for S. spallanzanii. Maximum retention was recorded after 30 min for both species. The obtained results contribute to the knowledge of the two polychaetes’ filtration activity and to characterize the filtration process on harmful microalgae in light of the protection of water resources and human health. Both species, indeed, were extremely efficient in removing A. carterae from seawater, thus suggesting their employment as a new tool in mitigation technologies for the control of harmful algae in marine environments, as well as in the aquaculture facilities where HABs are one of the most critical threats

Shift in Sabella spallanzanii (Polychaeta, Sabellidae) spawning period in the Central Mediterranean Sea: a consequence of climate change?

Sabella spallanzanii is a large tubicolous filter feeder polychaete common in the Mediterranean fouling assemblages where it plays an important role in structuring the community. Its reproductive biology is well known and had been investigated since 1993. During the past few years a shift in its reproductive period has been observed. In 2008 the presence of ripe eggs in the females was observed at least two months in advance compared to the past. This was confirmed during the 2009 when spawning and fertilization were observed three months in advance compared to the past. Possible causes of this shift may be related to the increasing surface temperature in the Central Mediterranean Sea

Sabellidae (Annelida) from the Faro coastal lake (Messina, Ionian Sea), with the first record of the invasive species Branchiomma bairdi along the Italian coast

In the present paper, morphological and ecological observations on 4 sabellid taxa, Branchiomma bairdi, B. luctuosum,Megalomma lanigera and Myxicola sp., collected from the coastal lake of Faro (Messina, Ionian Sea) (26-36 psu), are reported. Megalomma lanigera, Myxicola sp. and B. luctuosum were collected from the soft bottom in shallow water and B. bairdi from the hard bottom of an internal channel. The presence of the latter is remarkable, as there is no previous record of this species along the Italian coast, and it confirms the lake of Faro as a very favourable environment for the introduction of alien species, which has occurred frequently as a result of aquaculture. High intraspecific variation was observed for M. lanigera, whilst more extensive analysis is required to ascertain the taxonomic status of the Myxicola specimens, including a review of all Mediterranean data currently attributed to M. infundibulum

Regeneration as a novel method to culture marine ornamental sabellids

Collection of live invertebrates from coral reefs has increased dramatically over the past two decades in response to the growing marine aquarium industry, and currently, more than 500 species (excluding corals) are traded globally. Aquaculture of ornamental species is deemed a priority solution in mitigating the effects of wild collection but expanding the range of species is limited by bottlenecks at key life history stages. A novel culture method for ornamental sabellids, which utilises their outstanding regenerative capacity in a process similar to coral ‘fragging’, has been developed and survivorship after regenerative development assessed. Sabella pavonina, a temperate species found around the UK, was used as a model to develop a culture technique which was subsequently transferred to a tropical species of Sabellastarte. Survivorship of S. pavonina was high (≥80%) in individuals which had been cut into as many as eight fragments and all fragments completed regenerative development within a four week period. Sabellastarte species exhibited ≥75% survivorship when cut into just two fragments, but higher mortality was recorded with increasing number of cuts, with only 20% of fragments from individuals cut into eighths surviving the duration of the experiment. Both test species were capable of regenerating cephalically and caudally within a four week period. Caudal regeneration involved the healing of the cut surface, reconstruction of the pygidium and subsequent segment addition, while cephalic regeneration was a more complex process of wound healing, reconstruction of a new mouth and the development of the branchial crown structure. It is concluded that differences in survivorship between S. pavonina and Sabellastarte sp. could be attributed to either infection due to sub-optimal water quality in the test tanks, or species-specific differences in the area of wound size in relation to the length of the fragment. Optimisation of survivorship and the speed of regenerative growth could be improved with the enhancement of the culture system

Shift in Sabella spallanzanii (Polychaeta, Sabellidae) spawning period in the Central Mediterranean Sea: a consequence of climate change?

Sabella spallanzanii is a large tubicolous filter feeder polychaete common in the Mediterranean fouling assemblages where it plays an important role in structuring the community. Its reproductive biology is well known and had been investigated since 1993. During the past few years a shift in its reproductive period has been observed. In 2008 the presence of ripe eggs in the females was observed at least two months in advance compared to the past. This was confirmed during the 2009 when spawning and fertilization were observed three months in advance compared to the past. Possible causes of this shift may be related to the increasing surface temperature in the Central Mediterranean Sea