Ultrastructure of spermatozoa of the caridean shrimps of Brazil: a modern taxonomic approach through morphological and phylogenetic integration

• Grant number: 23/01445-8
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Effective date (Start): June 01, 2023
• Effective date (End): May 31, 2025
• Field of knowledge: Biological Sciences - Zoology - Morphology of Recent Groups
• Principal Investigator: Fernando Jose Zara
• Grantee: Caio dos Santos Nogueira
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil
• Associated research grant: 18/13685-5 - Integrative analysis of the Brazilian fauna of decapod crustaceans: taxonomy, phylogenetic systematics, spermiotaxonomy, morphology of post-embryonic development, ecology and conservation, AP.BTA.TEM

Abstract

The spermatozoa ultrastructure, or spermiotaxonomy, is an important tool that can differentiate closely related groups based on key spermatozoa characters. There have been many studies on crustaceans with this focus, and most of them have addressed brachyuran and anomuran crab species. However, few integrate different techniques of electron and optical microscopy for a complete description, and there is no methodological standard to be followed. Little is known about the ultrastructure of shrimp spermatozoa, especially caridean shrimps. Thus, the present proposal aims to describe the ultrastructure of spermatozoa of representatives of all families of caridean shrimps that occur in Brazil through the integration of electron and optical microscopy, filling the gap that exists on the sperm morphology of these organisms in the world. With this, a new sperm description protocol will be proposed with the aim of seeking a high-quality descriptive pattern, resolving numerous discretionary problems found in the literature. After the description, we will analyze whether the sperm ultrastructure supports the proposed phylogenetic relationships between the families and genera of caridean shrimps and how the sperm characters evolved among the families of this basal clade of Pleocyemata. Additionally, and for the first time, we will introduce geometric morphometric analyses as an additional tool for comparing sperm shape at the species level. The shrimps will be collected in freshwater and marine environments using different sampling methods according to the habitat. Sieves and traps will be used for freshwater collections, while diving and the installation of artificial refuge substrates will be performed in the marine environment. All collected material will be processed and subjected to scanning and transmission electron microscopy analyses and also differential interference contrast microscopy to create a gold standard for spermiotaxonomy. Subsequently, the spermatozoa ultrastructure of each organism will be compared and integrated with molecular phylogeny, and we will seek for traits that vary between families and genera, allowing us to reconstruct the evolutionary history of the spermatozoan in this infraorder.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

ADRIANE CANDIOTTO; CAIO S. NOGUEIRA; LAURA SCHEJTER; ALEXANDRE R. DA SILVA. Sexual and size dimorphism in two deep-water hermit crabs (Decapoda: Parapaguridae) from the Western Atlantic Ocean. Nauplius, v. 31, 2023-12-04. (23/01445-8, 19/00661-3)