Do Morphological Similarities and human-induced dispersal explain the non-native occurrence of Serpulidae (Annelida) in Southwest Atlantic? Taxonomic detailing is the key

Abstract

Species of Serpulidae are common on benthic and biofouling communities, occurring attached on both natural and artificial substrates. In this paper, Serpulids were collected from intertidal to subtidal areas, on rocky shore and suspended artificial plates in port areas. Herein we report three new records of serpulid species to the coast of Rio de Janeiro, Brazil. We also discuss the misidentification of Spirobranchus tetraceros, which was previously reported to the north of Rio de Janeiro.

On a new species of Spirobranchus Blainville, 1818 (Annelida: Serpulidae) and considerations on the genus along the Brazilian coast

“…Perry et al (2018) alert that S. tetraceros is an extensively distributed complex of species, though that do not exclude the likelihood of either of these species being introduced distant to the type-locality. The specimens we analyzed are compatible with descriptions of S. tetraceros, and the occurrence of this exotic species in Brazil was recently noticed (Rodrigues et al, 2020), thus we retain the identification of the mentioned previous authors. Members of S. tetraceros share with those of S. giganteus the tube with a pointed longitudinal keel, operculum ornamented by thorns, and special collar chaetae.…”

“…More recently, S. giganteus has also been recorded in the southeastern region of Brazil (Skinner et al, 2012) and S. minutus (Rioja, 1941) has been registered in the northeastern region (Ananias, 2017), demonstrating that the distributions of both species could be underestimated. Although initially misidentified as S. giganteus (Skinner et al, 2012), Spirobranchus tetraceros (Schmarda, 1861) became the third species of the genus recorded in Brazil based on specimens from different parts of the State of Rio de Janeiro (Perry et al, 2017;Rodrigues et al, 2020). In the present study, using a morphological approach, we describe a new species of Spirobranchus from the southeastern coast of Brazil, representing the first record of members of the S. kraussii complex from the western Atlantic.…”

“…Brazilian specimens of S. tetraceros were actually identified as belonging to S. giganteus by Skinner et al (2012), in part of the material used for that study, but that mistake was corrected by Perry et al (2017). The operculum of specimens of S. tetraceros has a conical endplate, or up to four branched concentric thorns (ten Hove, 1970;Rodrigues et al, 2020), whereas that of members of S. giganteus has two dorsolateral thorns and, frequently, a bifurcated mid-ventral thorn. Furthermore, whereas animals belonging to S. giganteus have individual compound eyes at the base of each dorsal-most radiolus, members of S. tetraceros only have simple ocelli scattered along the radioles and they present interradiolar processes, which are absent among members of S. giganteus.…”

“…(Cnidaria: Anthozoa: Scleractinia). Also found on artificial substrata, such as concrete blocks and plastic incrustation plates (Rodrigues et al, 2020). Distribution: Indian Ocean: Australia, Phillipines, off China (Sun et al, 2012), Red Sea (Perry et al, 2017), Aqaba Gulf, eastern coast of Africa and Madagascar (Read, 2019); Pacific Ocean: Australia; Atlantic Ocean: Mediterranean Sea, Greek, Caribbean Sea (ten Hove, 1970), Gulf of México, Colombia (Read, 2019) and southeastern Brazil, at Rio de Janeiro state (Skinner et al, 2012;Rodrigues et al, 2020).…”

Record of the non-indigenous species Sternaspis aff. nana Zhadan, Tzetlin & Salazar-Vallejo, 2017 (Annelida: Sternaspidae) in the Southwest Atlantic Ocean

“…More than 292 species of marine polychaetes, belonging to 164 genera, have been reported as NIS globally, most of them Syllidae Grube, 1850, Spionidae Grube, 1850, Sabellidae Latreille, 1825, Serpulidae Rafinesque, 1815and Nereididae Blainville, 1818(Çinar, 2013. Among the approximately 46 polychaeta species classified as NIS in Brazil (Rodrigues et al, 2020), eight are invasive exotic species (I3N, 2018). To date, non-indigenous Sternaspidae has not been recorded on the Brazilian coast, but in the UK (Townsend et al, 2006;Shelley et al, 2008), India (Jose et al, 2014) and Egypt (Abdelnaby, 2020), Sternaspis scutata (Ranzani, 1817) has been recorded as a non-native or invasive polychaeta.…”