Variation in larval traits between closely related species of freshwater prawns (Macrobrachium amazonicum and M. pantanalense)

Author(s)

Nogueira, Caio Santos ; Costa, Rogerio Caetano ; Pantaleao, Joao Alberto Farinelli

• Document type: Journal article
• Source: ACTA ZOOLOGICA; v. 105, n. 4, p. 15-pg., 2023-12-03.

Abstract

Larval morphology is a valuable tool for understanding the life history of decapod crustaceans. This approach has proven valuable in confirming taxonomic revisions based on molecular or adult morphology analyses. Therefore, the present study aimed to compare larval traits (e.g. development time, morphology, and larval size) between Macrobrachium amazonicum and M. pantanalense, two closely related species that are separated by a low genetic distance. The first five zoeal stages of each phenotype and species were analysed. Differences in larval development time, morphology, and size were observed. M. amazonicum exhibits faster development during the early larval stages compared to M. pantanalense. The main morphological difference between the two species is related to the stage at which pereiopod five develops as a functional appendage, namely zoea IV in M. amazonicum and zoea III in M. pantanalense. In addition, size variation was observed, with M. pantanalense larvae being larger in the early stages. The differences found between the two species corroborate that M. amazonicum and M. pantanalense are distinct lineages. Even though these groups are separated by a low genetic distance, the existing differences are conclusive, and therefore, these organisms can be considered as two distinct taxonomic entities. (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: 18/13685-5 - Integrative analysis of the Brazilian fauna of decapod crustaceans: taxonomy, phylogenetic systematics, spermiotaxonomy, morphology of post-embryonic development, ecology and conservation
• Grantee: Fernando Luis Medina Mantelatto
• Support Opportunities: BIOTA-FAPESP Program - Thematic Grants
• FAPESP's process: 19/00661-3 - A comparative interdisciplinary analysis between the prawns Macrobrachium amazonicum (Heller, 1862) and Macrobrachium pantanalense (dos Santos, Hayd & anger, 2013) support the interspecific differentiation?
• Grantee: Caio dos Santos Nogueira
• Support Opportunities: Scholarships in Brazil - Doctorate