Mollusks associated with the Avicennia schaueriana (Magnoliophyta: Acanthaceae) roots of a hypersaline estuary in northeastern Brazil

• Published in: Acta limnológica brasiliensia 2019, Vol.31, p.1-5
• Main Authors: Muniz, Ana Priscila Amancio, Duarte, Rafaela Cristina de Souza, Mota, Ellori Laíse Silva, Lima, Jessica de Oliveira, Dias, Thelma Lúcia Pereira
• Format: Article
• Language: English
• Subjects: Abundance; Avicennia; Avicennia schaueriana; Biodiversity; Bivalvia; Brackishwater environment; Ecosystems; Estuaries; Estuarine dynamics; Estuarine environments; estuário; florestas de mangue; Forests; Gastropoda; gastrópodes; Genera; Habitats; Hydrologic cycle; Hydrological cycle; invertebrados; Invertebrates; LIMNOLOGY; Mangrove swamps; Mangroves; Marine molluscs; Measuring instruments; Microhabitat; Microhabitats; Mollusks; Roots; Salinity; Salinity gradients; Species richness; Taxonomy; Waterways
• ISSN: 2179-975X; 0102-6712; 2179-975X
• DOI: 10.1590/s2179-975x4918

Abstract Aim Avicennia schaeuriana is one of the six species that composes the mangrove forests of Brazil and form mangrove fringes along waterways. The mangrove-roots of the A. schaeuriana act as one of the microhabitats used by the invertebrate biodiversity of the estuarine ecosystem. The present note aimed to inventory the malacofauna associated with roots of Avicennia schaueriana of the hypersaline and inverse estuary, highlighting variations in abundance and diversity along a salinity gradient and different seasonal periods. Methods Three sampling stations were delineated along the course of the estuary. At each station 3 transects of 10 meters were placed, and for each of them 3 sample points were selected, and at each point 3 samples of roots of A. schaueriana were obtained. A total of 108 samples were stored in plastic bags containing 4% formaldehyde and subsequently passed through a screening process, with identification of the associated specimens with the lowest possible taxonomic level. Results A total of 171 specimens was recorded, belonging to 10 species, 7 families, and 9 genera of the Bivalvia and Gastropoda classes. The abundance of the specimens differed between the seasonal periods analyzed. Conclusions The highest species richness and abundance of organisms in the rainy period allows inferences about the importance of the estuarine water cycle in regulating the biodiversity of these environments. Thus, the importance of the maintenance and protection of the mangrove forests composed of A. schaueriana, as well as the need for more in-depth studies becomes evident. Resumo Objetivo Avicennia schaeuriana é uma das seis espécies que compõem as florestas de mangue do Brasil e formam franjas de mangue ao longo dos cursos d’água, sendo diretamente influenciadas pela maré. As raízes do mangue A. schaeuriana atuam como um dos microhábitats utilizados pela biodiversidade de invertebrados do ecossistema estuarino. Este estudo objetivou inventariar a malacofauna associada às raízes de Avicennia schaueriana em um estuário hipersalino e inverso, destacando variações na abundância e diversidade ao longo de um gradiente de salinidade e em períodos sazonais distintos. Métodos Foram delimitadas três estações amostrais ao longo do curso do estuário. Em cada estação foram posicionados 3 transectos de 10 metros paralelos a margem e para cada um deles foram sorteados previamente 3 pontos amostrais aleatórios e em cada ponto foram obtidas 3 amostras de raízes