The Second Antenna of Caridean Shrimps: An Approach on the Variation of Flagellar Setae among Species with Different Mating Systems

Author(s)

Nogueira, Caio Santos ; Santos, Rafael Carvalho ; Jaconis, Milena Silva ; Pescinelli, Regis Augusto

• Document type: Journal article
• Source: BIOLOGICAL BULLETIN; v. N/A, p. 11-pg., 2024-04-01.

Abstract

The setae on the antennae of caridean shrimps perform chemoreceptive functions, including the identification of potential mating partners. Variation in the number of setae on the antennal flagellum has been reported as a sexually dimorphic trait in these organisms. This difference is correlated with the distinct mating systems and reproductive behaviors of these animals. This study investigates the variation in the number of antennal flagellar setae in four species of shrimps from the genus Macrobrachium, which are grouped into two distinct mating systems. Two species with a pure search mating system (M. jelskii and M. pantanalense) and two with a neighborhoods of dominance mating system (M. acanthurus and M. olfersii) were analyzed. The setae were quantified using light microscopy, morphologically characterized through scanning electron microscopy, and then compared among the demographic groups of each species. The results show that in the pure search species, males possess a significantly higher number of setae than females (P < 0.01). In the neighborhoods of dominance species, dominant males of M. acanthurus and M. olfersii had more setae than subordinate males and females (P < 0.01). The same types of setae, denticulate and simple, were found in all species. We conclude that the variation in the number of flagellar setae is correlated with the mating system of each species and their specific reproductive behaviors, suggesting a morphological adaptation to optimize chemoreception in different reproductive events. These findings contribute to the understanding of reproductive strategies and sensory adaptations in crustaceans. (AU)

• FAPESP's process: 23/01445-8 - Ultrastructure of spermatozoa of the caridean shrimps of Brazil: a modern taxonomic approach through morphological and phylogenetic integration
• Grantee: Caio dos Santos Nogueira
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 23/16546-4 - MORPHOLOGICAL CHARACTERIZATION OF JUVENILES OF Xiphopenaeus dincao CARVALHO-BATISTA, TEROSSI, ZARA, MANTELATTO & COSTA, 2020 AND X. kroyeri (HELLER, 1862) FOR AN ECOLOGICAL AND POPULATION ASSESSMENT
• Grantee: Milena Silva Jaconis
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 24/01176-0 - Filling gaps in the life history of alpheid shrimp: description of larval morphology and molecular approach of native and non-native species from paulista coast
• Grantee: Régis Augusto Pescinelli
• Support Opportunities: Regular Research Grants
• FAPESP's process: 24/13154-0 - Larval morphology of carid shrimps: application of different microscopic tools for taxonomy and systematics
• Grantee: Rafael de Carvalho Santos
• Support Opportunities: Scholarships in Brazil - Support Program for Fixating Young Doctors