Chemical and visual recognition in the association between the shrimps Salmoneus carvachoi Anker, 2007 (Caridea, Alpheidae), and Alpheus estuariensis Christoffersen, 1984 (Caridea, Alpheidae), and the fish Gobionellus stomatus Starks, 1913 (Perciformes, Gobiidae)

The occurrence of symbiotic relationships, are common in nature, but still require more understanding of the mechanisms that facilitate these interactions. Observations in estuarine environments in the Western Atlantic have shown that burrows constructed by snapping shrimp Alpheus estuariensis are frequently co-occupied by another shrimp species, Salmoneus carvachoi and a goby fish, Gobionellus stomatus. The shrimp-shrimp and goby-shrimp interactions observed by previous researches showed that these crustaceans find their partners using olfactory cues, while gobies rely on visual cues. The objective of the present study was to test visual or chemical cues experimentally that were believed to establish associations between Salmoneus carvachoi and Alpheus estuariensis shrimps. The second aim was to test the hypothesis that A. estuariensis is chemically attracted to goby fish and the latter is visually attracted to A. estuariensis. The result of the experiments that included a series of controls, showed that there was no significant attraction of the A. estuariensis for G. stomatus or vice versa. However, S. carvachoi was attracted to A. estuariensis in both the chemical and visual attraction experiments. It was hypothesized that the use of the refuges constructed and maintained by A. estuariensis, and the benefits provided by the refuges, are the main reasons for the co-occurrence of S. carvachoi and G. stomatus in burrows constructed by the shrimp A. estuariensis.