Evolution of Staurozoa (Cnidaria): molecular, morphological and cnidome inferences

Author(s)

Lucília Souza Miranda

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB)
• Defense date: 2014-10-14

Examining board members

Antonio Carlos Marques; Federico David Brown Almeida; Marcelo Visentini Kitahara; Tito Monteiro da Cruz Lotufo; Alvaro Esteves Migotto

• Advisor: Antonio Carlos Marques

Abstract

Staurozoa is one of the five current classes of the phylum Cnidaria. In this Dissertation we propose an integrative study of the evolution of Staurozoa, encompassing molecular, morphology, and cnidome information. In order to address these different aspects, the general aims of this project are to infer (1) the evolutionary relationship between species of Staurozoa; (2) the evolution of the body plan in Staurozoa; and (3) the taxonomic and evolutionary meaning of cnidome for the class. The chapter \"Global diversity and phylogenetic systematics of stalked jellyfishes (Cnidaria: Staurozoa)\" presents a comprehensive phylogenetic hypothesis for representatives of the class Staurozoa. This hypothesis supported an extensive reassessment of staurozoan classification. The study also presents an historical review of the class, including information on taxonomy, diversity, geographical and bathymetric distribution, use of substrate, feeding, behavior, life cycle, and conservation. In the chapter \"Evolution of the body plan in Staurozoa (Cnidaria): a comparative histological study\", the internal anatomy of 10 species was evolutionarily analyzed based on our molecular phylogenetic hypothesis for the class. Characters rarely studied for the group were comparatively described in detail, and their possible functions were discussed. The evolution of nematocysts in Staurozoa is analyzed in the chapter \"Phylogenetic signal of nematocysts in Staurozoa (Cnidaria)\". Data from 17 species were analyzed based on our phylogenetic hypothesis. Using traditional and geometric morphometric data, we concluded that there is a significant phylogenetic signal for the nematocysts from secondary tentacles, which was not observed for the nematocysts from white spots. The possible relationship of phylogenetic signal and development of nematocysts in Staurozoa is discussed, as well as the possible evolutionary pressures involved in the presence and absence of phylogenetic signal (AU)

• FAPESP's process: 10/07362-7 - Evolution in Staurozoa: molecular, morphological, cnidome and developmental subsidies
• Grantee: Lucília Souza Miranda
• Support Opportunities: Scholarships in Brazil - Doctorate