Phylogenetic relationships of Proboscoida Broch, 1910 (Cnidaria, Hydrozoa): Are traditional morphological diagnostic characters relevant for the delimitation of lineages at the species, genus, and family levels?

Author(s)

Cunha, Amanda F. ; Collins, Allen G. ; Marques, Antonio C.

• Document type: Journal article
• Source: Molecular Phylogenetics and Evolution; v. 106, p. 118-135, JAN 2017.
• Web of Science Citations: 11

Abstract

Overlapping variation of morphological characters can lead to misinterpretation in taxonomic diagnoses and the delimitation of different lineages. This is the case for hydrozoans that have traditionally been united in the family Campanulariidae, a group known for its wide morphological variation and complicated taxonomic history. In a recently proposed phylogenetic classification of leptothecate hydrozoans, this family was restricted to a more narrow sense while a larger Glade containing most species traditionally classified in Campanulariidae, along with members of Bonneviellidae, was established as the suborder Proboscoida. We used molecular data to infer the phylogenetic relationships among campanulariids and assess the traditional classification of the family, as well as the new classification scheme for the group. The congruity and relevance of diagnostic characters were also evaluated. While mostly consistent with the new phylogenetic classification of Proboscoida, our increased taxon sampling resulted in some conflicts at the family level, specially regarding the monophyly of Clytiidae and Obeliidae. Considering the traditional classification, only Obeliidae is close to its original scope (as subfamily Obeliinae). At the genus level, Campanularia and Clytia are not monophyletic. Species with Obelia-like medusae do not form a monophyletic group, nor do species with fixed gonophores, indicating that these characters do not readily diagnose different genera. Finally, the species Orthopyxis integra, Clytia gracilis, and Obelia dichotoma are not monophyletic, suggesting that most of their current diagnostic characters are not informative for their delimitation. Several diagnostic characters in this group need to be reassessed, with emphasis on their variation, in order to have a consistent taxonomic and phylogenetic framework for the classification of campanulariid hydrozoans. (C) 2016 Elsevier Inc. All rights reserved. (AU)

• FAPESP's process: 11/22260-9 - Morphological variation and its phylogenetic signal in marine colonial organisms: a study with the family Campanulariidae (Cnidaria, Hydrozoa)
• Grantee: Amanda Ferreira e Cunha
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 13/50484-4 - Biodiversity and distribution patterns of the Medusozoa form the South-Western Atlantic
• Grantee: Antonio Carlos Marques
• Support Opportunities: Regular Research Grants
• FAPESP's process: 11/50242-5 - Dimensions of marine life: patterns and process of diversifications in planktonic and benthic cnidarians
• Grantee: Antonio Carlos Marques
• Support Opportunities: BIOTA-FAPESP Program - Thematic Grants
• FAPESP's process: 13/25874-3 - Morphological variability and its phylogenetic signal in marine colonial organisms: a case study with the family Campanulariidae (Cnidaria, Hydrozoa)
• Grantee: Amanda Ferreira e Cunha
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• FAPESP's process: 04/09961-4 - Biodiversity, evolution, endemism and conservation of the Medusozoa from the Southwestern Atlantic
• Grantee: Antonio Carlos Marques
• Support Opportunities: Research Projects - Thematic Grants