cylindracea) are nowadays common on these shallow environments, displacing
numerous indigenous species.
Two different strata (sediment and frond) form the habitat of macroalgal communities, and the associated species use these microhabitats selectively. For example, the molluscs inhabiting the algal fronds are dominated by microalgae or
periphyton grazers, whereas depositivores, plankton and seston feeders and carnivores dominate the sediment in the underlying stratum (Urra et al. 2013a). Among
the most characteristic animal species in these algal communities of calm environments are the sea urchins Paracentrotus lividus and Arbacia lixula, which graze on
the algae, allowing the installation of some sessile animals such as A. sulcata or
Aiptasia mutabilis, or even generate barren rock surfaces known locally as
“blanquizales”, where crustose coralline algae of the genus Lithophyllum dominate
the substrate.
In the Alboran Sea, invertebrate communities associated with infralittoral
macroalgal beds are dominated by crustaceans and molluscs, followed by echinoderms and polychaetes. Most published works on macroalgal communities of the
Alboran Sea were focused on communities associated with H. scoparia and
Ellisolandia elongata beds of the northwestern part. The brown macroalgae
H. scoparia provides shelter to an astoundingly diverse array of small animals,
mostly molluscs (ca. 200 species), crustaceans (ca. 100 peracarid species, mainly
amphipods; 35 decapod species) and polychaetes (over 80 species) (SánchezMoyano and García-Gómez 1998; Conradi and López-González 1999; López and
Viéitez 1999; Sánchez-Moyano et al. 2002; Castellanos et al. 2003; López and
Gallego 2006; Urra et al. 2013a; Mateo-Ramírez et al. 2018). Gastropods such as
Rissoa guerinii, Bittium reticulatum, Nodulus contortus and Eatonina fulgida or
bivalves such as Musculus costulatus were the most abundant species on these
H. scoparia beds (Urra et al. 2013a). Regarding crustaceans, Conradi and LópezGonzález (1999) found 116 benthic gammarid amphipod species inhabiting different
habitats of Algeciras Bay, of which 41 occurred in H. scoparia. In relation with other
peracarid taxa, the tanaidaceans Chondrochelia dubia and Tanais dulongii, the
cumaceans Cumella limicola and Nannastacus unguiculatus as well as the isopods
Paranthura nigropunctata and Stenosoma capito were the most abundant species on
H. scoparia beds of the Strait of Gibraltar (Guerra-García et al. 2009b). Regarding
decapods, Hippolyte leptocerus, Pilumnus hirtellus, Sirpus zariquieyi, Acanthonyx
lunulatus, Athanas nitescens and Achaeus gracilis were the dominant species in
shallow algal communities from Málaga coast (Mateo-Ramírez et al. 2018). The
study by Acero and San Martín (1986) on polychaetes of the first horizon of
photophilous algae from localities of the Alboran Sea (Málaga) and nearby Atlantic
(Cádiz) showed a similar species composition, but diversity was higher in Mediterranean samples, probably due to the stronger tides in the Atlantic area. López and
Viéitez (1999) studied the polychaete assemblages associated with different algae
beds from Chafarinas Islands. They reported ca. 37 species inhabiting the community of algae exposed to wave action (Ellisolandia elongata, Asparagopsis armata,
Cystoseira tamariscifolia and Laurencia obtusa facies), with Syllis prolifera,
Salvatoria vieitezi, Exogone naidina, Sphaerosyllis hystrix or Amphiglena
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J. L. Rueda et al.
numerous indigenous species.
Two different strata (sediment and frond) form the habitat of macroalgal communities, and the associated species use these microhabitats selectively. For example, the molluscs inhabiting the algal fronds are dominated by microalgae or
periphyton grazers, whereas depositivores, plankton and seston feeders and carnivores dominate the sediment in the underlying stratum (Urra et al. 2013a). Among
the most characteristic animal species in these algal communities of calm environments are the sea urchins Paracentrotus lividus and Arbacia lixula, which graze on
the algae, allowing the installation of some sessile animals such as A. sulcata or
Aiptasia mutabilis, or even generate barren rock surfaces known locally as
“blanquizales”, where crustose coralline algae of the genus Lithophyllum dominate
the substrate.
In the Alboran Sea, invertebrate communities associated with infralittoral
macroalgal beds are dominated by crustaceans and molluscs, followed by echinoderms and polychaetes. Most published works on macroalgal communities of the
Alboran Sea were focused on communities associated with H. scoparia and
Ellisolandia elongata beds of the northwestern part. The brown macroalgae
H. scoparia provides shelter to an astoundingly diverse array of small animals,
mostly molluscs (ca. 200 species), crustaceans (ca. 100 peracarid species, mainly
amphipods; 35 decapod species) and polychaetes (over 80 species) (SánchezMoyano and García-Gómez 1998; Conradi and López-González 1999; López and
Viéitez 1999; Sánchez-Moyano et al. 2002; Castellanos et al. 2003; López and
Gallego 2006; Urra et al. 2013a; Mateo-Ramírez et al. 2018). Gastropods such as
Rissoa guerinii, Bittium reticulatum, Nodulus contortus and Eatonina fulgida or
bivalves such as Musculus costulatus were the most abundant species on these
H. scoparia beds (Urra et al. 2013a). Regarding crustaceans, Conradi and LópezGonzález (1999) found 116 benthic gammarid amphipod species inhabiting different
habitats of Algeciras Bay, of which 41 occurred in H. scoparia. In relation with other
peracarid taxa, the tanaidaceans Chondrochelia dubia and Tanais dulongii, the
cumaceans Cumella limicola and Nannastacus unguiculatus as well as the isopods
Paranthura nigropunctata and Stenosoma capito were the most abundant species on
H. scoparia beds of the Strait of Gibraltar (Guerra-García et al. 2009b). Regarding
decapods, Hippolyte leptocerus, Pilumnus hirtellus, Sirpus zariquieyi, Acanthonyx
lunulatus, Athanas nitescens and Achaeus gracilis were the dominant species in
shallow algal communities from Málaga coast (Mateo-Ramírez et al. 2018). The
study by Acero and San Martín (1986) on polychaetes of the first horizon of
photophilous algae from localities of the Alboran Sea (Málaga) and nearby Atlantic
(Cádiz) showed a similar species composition, but diversity was higher in Mediterranean samples, probably due to the stronger tides in the Atlantic area. López and
Viéitez (1999) studied the polychaete assemblages associated with different algae
beds from Chafarinas Islands. They reported ca. 37 species inhabiting the community of algae exposed to wave action (Ellisolandia elongata, Asparagopsis armata,
Cystoseira tamariscifolia and Laurencia obtusa facies), with Syllis prolifera,
Salvatoria vieitezi, Exogone naidina, Sphaerosyllis hystrix or Amphiglena
302
J. L. Rueda et al.