The snails' tale in deep-sea habitats in the Gulf of Cadiz (NE Atlantic)

Abstract. Bridging the Atlantic and Mediterranean continental margins, the South Iberian region has recently been the focus for geological and biological investigations. In this region, the Gulf of Cadiz (GoC) encompasses a great variety of deep-sea habitats that harbour highly diverse biological communities. In this study, we describe the composition of gastropod assemblages obtained from in situ colonization experiments and benthic sampling of deep-sea habitats in the GoC. Gastropod distributional patterns, such as bathymetric ranges, bathymetric turnover, affinity to substrate types and abundance-occupancy relationships, are analysed and interpreted in relation to their inferred dispersal capabilities and substrate availability. Overall, the GoC comprises a high diversity of gastropods (65 species), and distinct assemblages were found in typical sedimentary environments at mud volcanoes and in association with carbonate and coral samples or organic substrata. The number of taxa peaked at the Carbonate Province in the middle slope (600–1200 m depth), a highly heterogeneous area with numerous mud volcanoes, carbonate mounds and corals. Darwin (1100 m) and Captain Arutyunov (1300 m) mud volcanoes harboured the most species-rich and abundant gastropod assemblages, respectively. Colonization experiments with organic substrata (wood and alfalfa grass) also yielded diverse and abundant gastropod assemblages. These organic inputs allowed the recruitment of local species but mainly of wood specialist taxa that were not previously known from the GoC. Our results suggest that the distribution of gastropod assemblages may be primarily determined by the occurrence of suitable habitats, probably due to the effect of the substrate type on the structural complexity of the habitat and availability and diversity of adequate food sources. The type of larval development is apparently not a limiting factor for colonization of deep-sea habitats. However, the predominance of non-planktotrophy, and especially lecithotrophy, suggests that a trade-off between more limited dispersal capability and higher potential for self-recruitment may be a recurrent pattern in gastropod species inhabiting reducing environments and other patchily distributed deep-sea habitats. A network of suitable habitats that ensures effective population connectivity would explain the predominance and relatively wide distribution of short-distance dispersing non-planktotrophic species in the GoC deep-sea habitats and other geographical regions.

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The snails' tale at deep-sea habitats in the Gulf of Cadiz (NE Atlantic)

Biogeosciences Discussions ◽

10.5194/bgd-10-3707-2013 ◽

2013 ◽

Vol 10 (2) ◽

pp. 3707-3733 ◽

Cited By ~ 2

Author(s):

L. Génio ◽

A. Warén ◽

F. L. Matos ◽

M. R. Cunha

Keyword(s):

Deep Sea ◽

Active Sites ◽

Feeding Strategies ◽

Limiting Factor ◽

Gulf Of Cadiz ◽

Gastropod Species ◽

Genus Level ◽

Geographical Regions ◽

Gulf Of Cádiz ◽

Suitable Habitats

Abstract. Bridging the Atlantic and Mediterranean continental margins, the South Iberian region has recently been the focus for geological and biological investigations. The Gulf of Cadiz (GoC) encompasses a great variety of deep-sea habitats that harbour highly diverse biological communities. In this study, we describe the taxa composition of gastropod assemblages from deep-sea habitats in the GoC and analyse the species distributional patterns in relation to their dispersal capabilities and substrate availability. Distinct gastropod assemblages were found at mud volcanoes, carbonate and coral sites, and organic-falls. Overall, the GoC comprises a high diversity of gastropods that include 65 taxa representing 32 families, 48 genera and 30 named species. The highest number of taxa was found at the highly heterogeneous carbonate province in the middle slope (500–1500 m depth), and higher abundance of individuals was observed in Captain Arutyunov mud volcano, one of the most active sites found in the GoC. Faunal similarities were found with Mediterreanean cold-seeps (species- and genus-level) and other chemosynthetic environments in the Atlantic and Pacific Oceans (genus-level). Colonization experiments with organic substrata (wood and alfalfa grass) yielded high abundances of gastropod species. These organic inputs allowed the recruitment of local species but also of wood specialist taxa that were not known to occur in the GoC. Our results suggest that distribution of gastropod assemblages may be primarily determined by the occurrence of suitable habitats probably due to effect of the substrate type on feeding strategies and that larval development is not a limiting factor for colonization of the deep sea. However, the predominance of non-planktotrophy, and especially lecithotrophy, suggests that the trade-off between a more limited dispersal capability and the higher potential for self-recruitment may be favoured by the gastropod species inhabiting reducing environments and other patchily distributed deep-sea habitats. A network of suitable habitats that ensures connectivity of effective populations would explain the predominance and relatively wide distribution of short-distance dispersing non-planktotrophic species at the GoC deep-sea habitats and other geographical regions.

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Additions to the Tanaidomorpha (Crustacea: Tanaidacea) from mud volcanoes and coral mounds of the Gulf of Cadiz and Horseshoe Continental Rise

Zootaxa ◽

10.11646/zootaxa.4377.4.3 ◽

2018 ◽

Vol 4377 (4) ◽

pp. 517

Author(s):

PATRICIA ESQUETE ◽

MARINA R. CUNHA

Keyword(s):

Deep Sea ◽

Type Species ◽

Shallow Waters ◽

Mud Volcanoes ◽

Gulf Of Cadiz ◽

Study Region ◽

Continental Rise ◽

Worldwide Distribution ◽

Gulf Of Cádiz ◽

First Time

The Tanaidacea collection from various research cruises carried out in the Gulf of Cadiz and Horseshoe Continental Rise between 2004 and 2012 yielded four species new to science that are described herein. Two belong to genera recorded for the first time since the original descriptions of their type species: Cetiopyge, described from the Gulf of Mexico and Gamboa from shallow waters of Macaronesia. The other two belong to the genera Collettea and Paragathotanais, both with a worldwide distribution. Additionally, specimens of Tumidochelia uncinata are described and illustrated to complete previous descriptions. Identification keys to all known genera of Nototanaidae, and the Eastern Atlantic species of Paragathotanais and Collettea are provided. This works raises the number of tanaidacean species known from the deep-sea habitats in the study region to a total of 22.

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Apseudomorph tanaidaceans (Crustacea: Peracarida) from mud-volcanoes in the Gulf of Cadiz (North-east Atlantic)

Zootaxa ◽

10.11646/zootaxa.2919.1.1 ◽

2011 ◽

Vol 2919 (1) ◽

pp. 1 ◽

Cited By ~ 6

Author(s):

MAGDALENA BŁAŻEWICZ-PASZKOWYCZ ◽

ROGER N. BAMBER ◽

MARINA R. CUNHA

Keyword(s):

Deep Sea ◽

Morphological Features ◽

The Other ◽

Mud Volcanoes ◽

Gulf Of Cadiz ◽

East Atlantic ◽

North East ◽

Gulf Of Cádiz ◽

Associated Species ◽

High Diversity

Faunal collections from mud-volcano sites in the Gulf of Cadiz, at depths between 355 and 3061 m, have revealed a high diversity (and in some cases high density) of tanaidaceans. A previous paper has described some of the tanaidomorph species found. Records of apseudomorph species from deep-sea chemosynthetic habitats are almost non-existent. The present study reports on seven apseudomorph species from five different genera from this material; two of the species, one in each of the genera Sphyrapus and Pseudosphyrapus are new to science, although there was insufficient material available to describe fully the Pseudosphyrapus species. Two of the other species are reported herein for only the second time. A neotype is erected for Apseudes setiferus Băcescu, and a lectotype for Sphyrapus malleolus Norman & Stebbing; these two, plus Atlantapseudes nigrifrons Băcescu and Fageapseudes retusifrons Richardson are redescribed. The habitus of Apseudes grossimanus is figured. None of the taxa appear to show any morphological features specifically adapted to the peculiar habitat around mud-volcanoes. The genus Collossella is relegated to the synonymy of Fageapseudes. The nonchemosynthetic-habitat-associated species Apseudes coriolis is moved to Taraxapseudes.

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Deep-sea ophiuroids (Echinodermata: Ophiuroidea: Ophiurida) from the Gulf of Cadiz (NE Atlantic)

Zootaxa ◽

10.11646/zootaxa.2754.1.1 ◽

2011 ◽

Vol 2754 (1) ◽

pp. 1 ◽

Cited By ~ 13

Author(s):

CLARA F. RODRIGUES ◽

GORDON L. J. PATERSON ◽

ANDREW CABRINOVIC ◽

MARINA R. CUNHA

Keyword(s):

Deep Sea ◽

Cold Water ◽

Cold Seep ◽

Mud Volcanoes ◽

Gulf Of Cadiz ◽

Ne Atlantic ◽

Morphological Adaptations ◽

Gulf Of Cádiz ◽

High Species Richness ◽

Distinct Separation

The Ophiuroidea collected from mud volcanoes and adjacent bathyal environments from the Gulf of Cadiz are reviewed. Thirteen species from six families—Ophiacanthidae, Ophiactidae, Amphiuridae, Amphilepididae, Ophiuridae and Ophiolepididae—were identified. A direct relationship to the chemosynthetic assemblages has not been established as the ophiuroids found in the mud volcanoes do not appear to have novel morphological adaptations and also occur in non-reducing environments. The ophiuroid fauna from the Gulf of Cadiz differs from other cold seep regions not only by the high species richness but also because members of Amphiuridae are dominant both in number of species and abundance. One species previously unknown, Ophiopristis gadensis sp. nov., (Ophiacanthidae) was collected from a dead cold-water coral thicket at the flank of a mud volcano and differs from its congeners in the type of disk spines which are more rugose and not smooth as in most of the other species, the presence of the thickened integument in larger specimens and the distinct separation between the oral papillae and the second oral tentacle scales.

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A relict oasis of living deep-sea mussels Bathymodiolus and microbial-mediated seep carbonates at newly-discovered active cold seeps in the Gulf of Cádiz, NE Atlantic Ocean

PalZ ◽

10.1007/s12542-021-00594-3 ◽

2021 ◽

Cited By ~ 1

Author(s):

Luis Somoza ◽

José Luis Rueda ◽

Francisco J. González ◽

Blanca Rincón-Tomás ◽

Teresa Medialdea ◽

...

Keyword(s):

Deep Sea ◽

Hydrothermal Vents ◽

Mud Volcano ◽

Cold Seeps ◽

Mud Volcanoes ◽

Gulf Of Cadiz ◽

The North ◽

Gulf Of Cádiz ◽

Ne Atlantic Ocean ◽

Mid Atlantic Ridge

AbstractExtensive beds of the deep-sea mussel Bathymodiolus mauritanicus (currently also known as Gigantidas mauritanicus) linked to active cold seeps related to fissure-like activity on Al Gacel mud volcano, Gulf of Cádiz, were filmed and sampled for the first time during the oceanographic expedition SUBVENT-2 aboard R/V Sarmiento de Gamboa. Al Gacel mud volcano is one of up to 80 fluid venting submarine structures (mud volcanoes and mud volcano/diapir complexes) identified in the Gulf of Cádiz as result of explosive venting of hydrocarbon-enriched fluids sourced from deep seated reservoirs. This mud volcano is a cone-shaped edifice, 107 m high, 944 m in diameter constituted by mud breccias and, partially covered by pavements of seep carbonates. Extensive beds of this deep-sea mussel were detected at the northern flank at 810–815 m water depth associated with bacterial mats around intermittent buoyant vertical bubble methane plumes. High methane concentrations were measured in the water column above living mussel beds. Other chemosymbiotic species (Siboglinum sp., Solemya elarraichensis, Isorropodon sp., Thyasira vulcolutre and Lucinoma asapheus) were also found in different parts of Al Gacel mud volcano. Al Gacel mud volcano may currently represent one of the most active mud volcanoes in the Gulf of Cádiz, delivering significant amounts of thermogenic hydrocarbon fluids which contribute to foster the extensive chemosynthesis-based communities detected. This finding is of paramount importance for linking extremophile bivalve populations along the North Atlantic, including cold seeps of the Gulf of México, hydrothermal vents of the Mid-Atlantic Ridge and now, detailed documented at the Gulf of Cádiz.

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Bryozoa from deep-sea habitats of the northern Gulf of Cádiz (Northeastern Atlantic)

Zootaxa ◽

10.11646/zootaxa.4768.4.1 ◽

2020 ◽

Vol 4768 (4) ◽

pp. 451-478 ◽

Cited By ~ 1

Author(s):

LAÍS V. RAMALHO ◽

CARLOS M. LÓPEZ-FÉ ◽

ANGEL MATEO-RAMÍREZ ◽

JOSÉ LUIS RUEDA

Keyword(s):

Atlantic Ocean ◽

Iberian Peninsula ◽

Deep Sea ◽

New Records ◽

Mud Volcanoes ◽

Gulf Of Cadiz ◽

Deep Waters ◽

Gulf Of Cádiz ◽

Northeastern Atlantic Ocean ◽

Northeastern Atlantic

This study examines material collected in the northern part of the Gulf of Cádiz, in the Northeastern Atlantic Ocean, between the Iberian Peninsula and northern Africa, at 300–1200 m depth, within the Site of Community Importance “Volcanes de fango del Golfo de Cádiz” (Mud volcanoes of the Gulf of Cádiz, ESZZ-12002). Several previous studies were carried out in the Iberian Peninsula and Moroccan area (shallow and deep waters), recording ca. 300 bryozoan species from the Gulf of Cádiz. In the present study a total of 40 bryozoan taxa were identified, including two species new to science—Antropora gemarita n. sp. and Microporella funbio n. sp.—and three new records for the area.

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