Gasterópodos asociados al alga calcárea Halimeda opuntia (Udoteaceae) en Puerto Rico

Abstract

Gastropods associated with the calcareous alga Halimeda opuntia (Udoteaceae) in Puerto Rico. Gastropod communities associated with the calcareous green alga Halimeda opuntia are described and compared for two Puerto Rico coral reefs: one in the northeast with front tradewinds (windward zone) and one in the southwest (leeward zone). We analyzed the content of 21 lots (2432 g) of H. opuntia from leeward zone and 15 lots (2448 g) from the windward zone. In total we recovered 526 gastropods (prosobranchs) classified in 54 taxa. Thirteen species of gastropods represented 79.6% of the community. Differences between species richness and mean density values were not significant (p>0.100). Forty species were identified from leeward and thirty one (31) species from windward. Gastropod mean density was 13.9 /100g of algae in leeward and 7.6/100g in windward. Significant differences were found for the Simpson Diversity Index (0.91 in the leeward and 0.82 in the windward community; t=3.44, α=0.005). We found no correlation between the weight of the algae and the frequency of the gastropods (R 2 =0.0893 in leeward, 0.0249 windward and 0.0923 for both). The relationship between species composition in lots of windward and leeward study sites was explored via polar ordination and no segregation was found. When compared, the gastropod communities found in H. opuntia collected in coral reefs in Puerto Rico were more similar within them than any other communities found in other genera of seaweed and in other environments. Our results agree with the hypothesis that H. opuntia offers the interstitial community a protected microhabitat from water movement impact. H. opuntia creates more homogenous conditions than those of the habitat where we found the algae. Rev. Biol. Trop. 56 (4) Las comunidades de moluscos asociados a macroalgas marinas en El Caribe han sido descritas por Warmke y Almodóvar (1963) y García-Ríos (1983). Warmke y Almodóvar (1963) recolectaron 25 especies de algas en el suroeste de Puerto Rico. Encontraron 90 especies de moluscos de los cuales 99% de los individuos eran gasterópodos. Al comparar los moluscos encontrados en algas rojas, verdes y pardas concluyeron que existe una mayor cantidad y diversidad de éstos asociados a las algas rojas. Sin embargo, de acuerdo a los datos de esa misma publicación, Halimeda opuntia (Linnaeus) Lamouroux, un alga verde calcárea, presentó mayor riqueza de especies que cualquiera de las especies de algas rojas.García-Ríos (1983) describió las comunidades de gasterópodos asociadas a macroalgas marinas, que se recolectaron en cuatro hábitats: costa rocosa, arrecife de coral, manglar expuesto al oleaje y canales de mangle. En ese trabajo se determinó que existe una mayor similitud entre las comunidades de gasterópodos que coexisten en el mismo hábitat, independientemente

Community structure and functional traits of mollusks associated with coastal reef macroalgae in Northeastern Brazil

“…Mollusk is one of the most conspicuous taxa in the phytal ecosystem, being composed mainly of small species with high taxonomic and functional richness. Some taxa are typical of this environment, especially those of the class Gastropoda (Chemello & Milazzo, ; García‐Ríos, Soto‐Santiago, Colón‐Rivera, & Medina‐Hernández, ; Kelaher et al, ; Marina, Urra, Rueda, & Sales, ; Queiroz & Dias, ).…”