Functional morphology of the setae of the carapace and pereopods in the decorator crab Macrocoeloma trispinosum (Latreille, 1825) (Crustacea: Decapoda: Brachyura)

• Grant number: 16/24503-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2017
• End date: December 31, 2017
• Field of knowledge: Biological Sciences - Zoology - Taxonomy of Recent Groups
• Principal Investigator: William Ricardo Amancio Santana
• Grantee: Amanda Lopes e Silva
• Host Institution: Pró-Reitoria de Pesquisa e Pós-Graduação. Universidade do Sagrado Coração (USC). Bauru , SP, Brazil

Abstract

Marine crabs compose the superfamily Majoidea Samuelle, 1819, popularly known as "spider crabs", which have enormous ecological importance in the maintenance of reef environments. Many crabs of this superfamily show a well-developed decoration behavior in which surrounding elements are adhered to the exoskeleton, which makes the majoideans also known as "decorator crabs". This habit provides protection against visuals predators, because allows the animals to camouflage very well in the environment. Exclusive morphological characteristics of this group facilitate the fixation of material in the exoskeleton, such as the presence of setae with hook-shape in the carapace functioning as a Velcro. However, this is not the only structure used to attach materials to the body. Very little is known about the possible auxiliary fixing mechanisms used by these animals. These uncertainties about the mechanisms of material fixation to the exoskeleton will be studied in Macrocoeloma trispinosum (Latreille, 1825), a model used to understand the structure and functional morphology of the different types of setae found in the carapace of majoideans. The aim here is to describe in detail the types setae of carapace and pereopods of Macrocoeloma trispinosum using light microscopy and scanning electron microscopy images and the types of the hooked setae using histological and histochemical analysis to understand which structures are used in the "decorator crabs". (AU)