Sea slugs (Gastropoda: Heterobranchia) from Rio Grande do Norte, Northeastern Brazil

Abstract

Heterobranch sea slugs (Gastropoda) present reduction, internalization, or absence of shell, and include more than 6,000 described species. Approximately 250 species are recorded from Brazil but only 14 had been previously recorded from Rio Grande do Norte, on the Brazilian northeastern coast. As a result of different expeditions conducted between 2008 and 2020, species were collected and identified. Among them, five species were recorded for the first time from the South Atlantic Ocean: Chelidonura hirundinina (Quoy & Gaimard, 1833); Sclerodoris prea (Ev. Marcus & Er. Marcus, 1967); Thuridilla malaquita Ortea & Buske, 2014; Berthella nebula Ghanimi, Schrödl, Goddard, Ballesteros, Gosliner & Valdés, 2020 and Berthella vialactea Ghanimi, Schrödl, Goddard, Ballesteros, Gosliner & Valdés, 2020. Thirty-six species are recorded for the first time from Rio Grande do Norte. The present survey expands the knowledge of the diversity of sea slugs from Brazil and supports the hypothesis of similarity between the heterobranch sea slug fauna from the northeastern Brazil and the Caribbean Sea.

DISTRIBUTION EXTENSION OF THE SEA SLUG Bursatella leachii BLAINVILLE, 1817 (GASTROPODA, HETEROBRANCHIA) ON RIO GRANDE DO NORTE, NORTHEAST BRAZIL

“…It feeds on plant and animal detritus from local sources (Braga et al 2017;Dhahri et al 2020). This species has a circumtropical distribution (Perissinoto et al 2014) occurring in Bermuda, Bonaire, Brazil, Colombia, Costa Rica, Cuba, Guadeloupe, Jamaica, Mexico, Panama, Puerto Rico, Trinidad and Tobago, the United States, and Venezuela (Gutiérrez et al 2015;Delgado et al 2022). It has also been recorded on the coast of Izmir in Turkey, in Lake St. Lucia, an estuary on the east coast of South Africa, in the Mediterranean Sea, as well as in the North Atlantic, other areas of the Caribbean, Japan, and India (Kazac and Cavas, 2007;Perissinoto et al 2014;Padula et al 2017;Bazicapulo et al 2018).…”

“…In the coastlines and mangroves of the Brazilian Northeast, it has been reported by Barroso and Mattews-Cascoon (2009) in the estuary region of the Ceará River, which covers around 500 hectares of mangrove, and in the coastal region of Alagoas in the Manguaba Lagoon estuary (Marcus 1972). It was first recorded on the coast of Rio Grande do Norte in Galinhos beach (Delgado et al 2022).…”

“…The marine ecorregion of Northeast Brazil is part of the Tropical Southwest Atlantic province, which is recognized for its high biodiversity attributed to the diverse environmental conditions and predominant ecosystems it encompasses, covering a significant biogeographic area (Spalding et al 2007). Within this ecological region lies the coastline of Rio Grande do Norte, which stretches for about 410 km and is characterized by various ecosystems, such as sandy beaches, rocky shores, coral reefs, some of which are protected areas, and the formation of tide pools that provide suitable habitats for the occurrence of B. leachii (Santos et al 2007;Delgado et al 2022).…”

“…The distance in kilometers along the coastline between each new occurrence and the first formal occurrence for Rio Grande do Norte (Delgado et al 2022) was considered as a measure of the species' distribution knowledge extension for the state. This procedure was performed using Google Earth software version 9.178.0.1, utilizing the OpenLayers interface version 6.15.1, in conjunction with Nodes.js program version 2022, adapting the methodology of Guimarães (2012).…”

“…This procedure was performed using Google Earth software version 9.178.0.1, utilizing the OpenLayers interface version 6.15.1, in conjunction with Nodes.js program version 2022, adapting the methodology of Guimarães (2012). The starting point for the extension calculation was the formal record by Delgado et al (2022), tracing a coastal route for each new record using latitude and longitude data. All data were compiled and organized in a table, highlighting the unpublished information up to the present moment.…”