The importance of molecular characters when morphological variability hinders diagnosability: systematics of the moon jellyfish genus Aurelia (Cnidaria: Scyphozoa)

PeerJ

article

Jonathan W. Lawley¹  Edgar Gamero-Mora¹  Maximiliano M. Maronna¹  Luciano M. Chiaverano³  Sérgio N. Stampar⁴  Russell R. Hopcroft⁵  Allen G. Collins⁶  André C. Morandini¹ 

[1] Departamento de Zoologia, Instituto de Biociências, Universidade de São Paulo;School of Environment and Science, Coastal and Marine Research Centre, Australian Rivers Institute, Griffith University;Instituto Nacional de Investigación y Desarrollo Pesquero;Departamento de Ciências Biológicas, Faculdade de Ciências e Letras, Universidade Estadual Paulista;College of Fisheries and Ocean Sciences, University of Alaska—Fairbanks;National Systematics Laboratory of the National Oceanic and Atmospheric Administration Fisheries Service, National Museum of Natural History, Smithsonian Institution;Centro de Biologia Marinha, Universidade de São Paulo

关键词: Cryptic species;    Diagnosis;    DNA barcoding;    Medusa;    Phylogeny;    Species delimitation;    Species description;    Synapomorphy;    Taxonomy;   

DOI  :  10.7717/peerj.11954

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

Cryptic species have been detected across Metazoa, and while no apparent morphological features distinguish them, it should not impede taxonomists from formal descriptions. We accepted this challenge for the jellyfish genus Aurelia, which has a long and confusing taxonomic history. We demonstrate that morphological variability in Aurelia medusae overlaps across very distant geographic localities. Even though some morphological features seem responsible for most of the variation, regional geographic patterns of dissimilarities are lacking. This is further emphasized by morphological differences found when comparing lab-cultured Aurelia coerulea medusae with the diagnostic features in its recent redescription. Previous studies have also highlighted the difficulties in distinguishing Aurelia polyps and ephyrae, and their morphological plasticity. Therefore, mostly based on genetic data, we recognize 28 species of Aurelia, of which seven were already described, 10 are formally described herein, four are resurrected and seven remain undescribed. We present diagnostic genetic characters for all species and designate type materials for newly described and some resurrected species. Recognizing moon jellyfish diversity with formal names is vital for conservation efforts and other studies. This work clarifies the practical implications of molecular genetic data as diagnostic characters, and sheds light on the patterns and processes that generate crypsis.

【 授权许可】

CC BY