The spreading of the non-native caprellid (Crustacea: Amphipoda) Caprella scaura Templeton, 1836 into southern Europe and northern Africa: a complicated taxonomic history.

Abstract

Caprella scaura, originally described by Templeton (1836) from Mauritius and later reported as several subspecies from numerous areas of the world, was found for the first time in the Mediterranean in 1994. Since this report, the species was found in several Mediterranean locations. To explore the current distribution of C. scaura in the Iberian Peninsula and adjacent areas, we surveyed marine fouling communities from 88 marinas along the whole Iberian Peninsula and North Africa, 3 from Italy, 1 from France, 1 from Malta and 1 from Greece between June 2011 and June 2012. The results of this survey report the first confirmed record of C. scaura in Corsica (France), Creta (Greece) and Morocco, and confirm an extensive distribution of C. scaura along the Spanish Mediterranean coast and the Strait of Gibraltar. The species was absent in the north Atlantic coast of Spain and the upper distribution limit in the eastern Atlantic coast is the locality of Cascais, in the south coast of Portugal. All populations studied belong to the same morphological form, with match with the subspecies C. scaura typica from Brazil and C. scaura scaura from Mauritius, suggesting that these two subspecies could correspond to the same “variety”.

Spreading and Establishment of the Non Indigenous Species Caprella scaura (Amphipoda: Caprellidae) in the Central Region of the Aegean Sea (Eastern Mediterranean Sea)

“…In the present paper, a new occurrence of Caprella scaura is reported for Greece, raising the total number of country records to three. Contrary to the previous two reports [32,47], where C. scaura was found in marinas, this is the first occurrence of the species on fish farm cages and the first in the northern part of the Aegean Sea, thus expanding the northernmost distribution range of the species in the region. Additionally, this is the first occurrence of the species on a cage from a sea bream/sea bass farm, since to the previous record occurrence was from tuna farms [14].…”

Quick spreading of the exotic amphipod Laticorophium baconi (Shoemaker, 1934): another small stowaway overlooked?

“…This indicates that the species could potentially reach natural habitats in other introduced regions, as the Mediterranean, where the species is still restricted to artificial habitats. Other exotic amphipods in the Mediterranean, such as Stenothoe georgiana, Caprella scaura or Paracaprella pusilla, have not been established in natural environments so far, being confined to artificial habitats in the introduced range (Ros et al, 2014a;Cabezas et al, 2019;Martínez-Laiz et al, 2020), but it is worth noting that the level of biofouling NIS spreading in natural habitats is still poorly investigated. On the contrary, high densities of the exotic Jassa slatteryi have already been recorded in Mediterranean natural habitats, including marine protected areas (Navarro-Barranco et al, 2018, 2023.…”

“…A molecular approach would aid to confirm L. bifurcatum as a different species to L. baconi, and to assess whether morphological variability of L. baconi is due to intraspecific variation or to the existence of a species complex. In any case, previous molecular and morphological works on other amphipods have revealed that, when a taxon with different 'forms' or 'varieties' within a complex rapidly spreads into an exotic range, only a single form of the complex is expanding its distribution range through anthropogenic vectors, while the other forms remain in a re-stricted distribution (e.g., Cabezas et al, 2014;Ros et al, 2014a). Furthermore, molecular evidence has supported that populations of all the worldwide distributed exotic amphipods investigated so far belong to single species, even when some degree of morphological variability is detected (Ashton et al, 2008;Cabezas et al, 2019;Beermann et al, 2020;Martínez-Laiz et al, 2020).…”

“…The early detection of certain non-indigenous amphipods in the Mediterranean region, such as the caprellids Caprella scaura Templeton, 1836 or Paracaprella pusilla Mayer, 1890, has been achieved through distinctive and easily recognizable characteristics (e.g., Ros et al, 2014a), which are strikingly different from those exhibited by related Mediterranean species (e.g., Krapp-Schickel, 1993). However, the time lag between an introduction and its first detection can be significantly delayed in taxonomically challenging non-indigenous amphipods (e.g., Jassa slatteryi Conlan, 1990 or Stenothoe georgiana Bynum & Fox, 1977), which could be largely overlooked due to misidentifications with morphologically similar native species (Bonifazi et al, 2018;Beermann et al, 2020;Martínez-Laiz et al, 2020).…”

Population biology of sympatric species of Caprella (Amphipoda: Caprellidae) in a tropical algal bed

“…Caprella danilevskii Czerniavski, 1868, C. equilibra Say, 1818 and C. scaura Templeton, 1836 are species with wide global distribution that occur in tropical and temperate coastal areas of various continents, suggesting that they have high levels of phenotypic plasticity and invasion potential (Mauro and Serejo 2015). Caprella scaura specifically is a successful invader in the Mediterranean Sea, spreading over coastal areas of Europe and North Africa in the last few decades (Guerra-García et al 2011, Ros et al 2014, Servello et al 2019. These species occur in sympatry in Sargassum beds in the northern coast of São Paulo state (Jacobucci et al 2009).…”